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Abstract

Background and aim: This technical review is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). It addresses the utilization of advanced endoscopic imaging in gastrointestinal (GI) endoscopy. Methods: This technical review is based on a systematic literature search to evaluate the evidence supporting the use of advanced endoscopic imaging throughout the GI tract. Technologies considered include narrowed-spectrum endoscopy (narrow band imaging [NBI]; flexible spectral imaging color enhancement [FICE]; i-Scan digital contrast [I-SCAN]), autofluorescence imaging (AFI), and confocal laser endomicroscopy (CLE). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendation and the quality of evidence. Main recommendations:1. We suggest advanced endoscopic imaging technologies improve mucosal visualization and enhance fine structural and microvascular detail. Expert endoscopic diagnosis may be improved by advanced imaging, but as yet in community-based practice no technology has been shown consistently to be diagnostically superior to current practice with high definition white light. (Low quality evidence.) 2. We recommend the use of validated classification systems to support the use of optical diagnosis with advanced endoscopic imaging in the upper and lower GI tracts (strong recommendation, moderate quality evidence). 3. We suggest that training improves performance in the use of advanced endoscopic imaging techniques and that it is a prerequisite for use in clinical practice. A learning curve exists and training alone does not guarantee sustained high performances in clinical practice. (Weak recommendation, low quality evidence.) Conclusion: Advanced endoscopic imaging can improve mucosal visualization and endoscopic diagnosis; however it requires training and the use of validated classification systems.

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... Image-enhanced endoscopy, including dye-assisted conventional chromoendoscopy and virtual chromoendoscopy, with or without magnification, is continually evolving in order to improve mucosal visualization and enhance fine structural and microvascular details [15,16,24,28]. ...
... Equipment-based virtual chromoendoscopy has the advantage of being relatively easy and ready to use. There are 2 types of virtual chromoendoscopy: optical chromoendoscopy and digital chromoendoscopy [6,8,28]. Optical chromoendoscopy technologies use optical lenses to narrow the bandwidth of spectral transmittance, thereby unveiling the mucosal and submucosal blood vessels-e.g., narrow-band imaging (NBI) (Olympus Medical Systems, Tokyo, Japan). ...
... Optical chromoendoscopy technologies use optical lenses to narrow the bandwidth of spectral transmittance, thereby unveiling the mucosal and submucosal blood vessels-e.g., narrow-band imaging (NBI) (Olympus Medical Systems, Tokyo, Japan). Digital chromoendoscopy technologies are based on the digital postprocessing of acquired images, resulting in enhanced tissue contrast-e.g., flexible spectral imaging color enhancement (FICE) (Fujinon Intelligent Chromo Endoscopy; Fujifilm, Tokyo, Japan) and i-Scan digital contrast (I-SCAN) (Pentax, Tokyo, Japan) [6,8,28]. More recently, an endoscopic system using laser as the light source has been developed (Blue Laser Imaging [BLI]; Fujifilm, Kanagawa, Japan). ...
Article
Colorectal malignant polyps (MP) are polyps with invasive cancer into the submucosa harboring a variable risk of lymph node involvement, which can be estimated through evaluation of morphological, endoscopic, and histologic features. The recent advances in imaging endoscopic techniques have led to the possibility of performing an optical diagnosis of T1 colorectal cancer, allowing the selection of the best therapeutic modality to optimize outcomes for the patient. When MP are diagnosed after endoscopic removal, their management can be challenging. Differentiating low- and high-risk histologic features that influence the possibility of residual tumor, the risk of recurrence and the risk of lymph node metastasis, is crucial to further optimize treatment and surveillance plans. While the presence of high-risk features indicates a need for surgery in the majority of cases, location, comorbidities and the patient's preference should be taken in account when making the final decision. This is a particularly important issue in the management of low rectal MP presenting with high-risk features, where chemoradiotherapy followed by a watch-and-wait strategy has demonstrated promising results. In this review we discuss the important prognostic features of MP and the most modern approaches regarding their management.
... Autofluorescence imaging (AFI) is based on the principle that there is an emission of light with a longer wavelength on the excitation of tissues with the light of a shorter wavelength. There are some endogenous tissue molecules in our gastrointestinal tract, such as flavins, collagen, nicotinamide adenine dinucleotide phosphate, that are fluorophores and emit fluorescence light with a longer wavelength when excited with short-wavelength light (26,(36)(37)(38)(39). Dysplastic and non-dysplastic Barrett's esophagus resulted in different autofluorescence characteristics due to different fluorophore contents (36,39). ...
... Autofluorescence imaging (AFI) is based on the principle that there is an emission of light with a longer wavelength on the excitation of tissues with the light of a shorter wavelength. There are some endogenous tissue molecules in our gastrointestinal tract, such as flavins, collagen, nicotinamide adenine dinucleotide phosphate, that are fluorophores and emit fluorescence light with a longer wavelength when excited with short-wavelength light (26,(36)(37)(38)(39). Dysplastic and non-dysplastic Barrett's esophagus resulted in different autofluorescence characteristics due to different fluorophore contents (36,39). In a multicenter RCT, 130 patients with Barrett's esophagus were randomly assigned to either Autofluorescence endoscopy (AFE)-target biopsy plus four-quadrant biopsies or conventional endoscopic surveillance with four-quadrant biopsies. ...
... Confocal Laser Endomicroscopy (CLE) is a technology developed for cellular and subcellular imaging up to 250 micrometers below the mucosal surface and thus provide real-time histology (in-vivo) during the procedure (36,41). Confocal Laser Endomicroscopy combines a confocal laser microscope as a probe that can pass through the channel of an endoscope or as a tip of a standard video endoscope. ...
Article
Full-text available
Gastroesophageal reflux disease (GERD) is one of the most common gastrointestinal diseases encountered in primary care and gastroenterology clinics. Most cases of GERD can be diagnosed based on clinical presentation and risk factors; however, some patients present with atypical symptoms, which can make diagnosis difficult. An esophagogastroduodenoscopy can be used to assist in diagnosis of GERD, though only half of these patients have visible endoscopic findings on standard white light endoscopy. However, the early complications of GERD may be hard to detect with standard white light endoscopy. This led to the development of new advanced endoscopic imaging techniques that is used to detect complications associated with GERD like Barrett's esophagus, and early esophageal adenocarcinoma. Treatment of GERD is important to prevent complications. Management of GERD includes lifestyle modifications, pharmacological therapy, endoscopic and surgical intervention. Minimally invasive endoscopic intervention can be an option in selected patients and without complications of GERD. These endoscopic interventions include endoscopic fundoplication, endoscopic mucosal resection techniques, ablative techniques, creating mechanical barriers, and suturing and stapling devices. As these new advanced endoscopic techniques are emerging, data surrounding the indications, advantages and disadvantages of these techniques need a thorough understanding.
... The images are then reconstructed using only a single selected wavelength for each red, green and blue component to finally display in real time a composite color-enhanced image [29]. ...
... Based on the studies reported in [33], [34] these technologies are useful in polyp characterization and are superior to standard WLE [34]. This is not the case however, for inflammatory bowel disease nor polyp detection where there is no significant improvement and its use is not recommended by the European Society of Gastrointestinal Endoscopy [29]. ...
... The spectral bandwidth of the green and blue channels is reduced from 50-70 nm to 20-30 nm. The final combination of the filtered signal and the red channel displays the micro-vessels in the mucosa and capillaries of layers, both appearing in a dark color due to the light absorption contrasting the reflected light coming from the rest of the mucosal tissue[29][30]. ...
Thesis
There exists an unmet clinical need to provide doctors with a new method that streamlines minimally invasive endoscopic treatment of colorectal cancer to single operator procedures assisted by in-situ and real-time accurate tissue characterization for informed treatment decisions. A promising solution to this problem has been developed at the ICube laboratory, in which the flexible interventional endoscope (Karl Storz) was completely robotized, so allowing a single operator to independently telemanipulate the endoscope and two insertable therapeutic instruments with a joint control unit. However, the robot-assisted flexible endoscope is subject to the same diagnostic accuracy limitations as standard endoscopy systems. It has been demonstrated that endoscopic optical coherence tomography (OCT) has a good potential for imaging disorders in the gastrointestinal tract and differentiating healthy tissue from diseased. Neither OCT, nor the robotized endoscope can solve the limitations of current standard of care for colon cancer management alone. Combining these two technologies and developing a new platform for early detection and treatment of cancer is the main interest of this work, with the aim of developing a state-of-the-art OCT imaging console and probe integrated with the robotized endoscope. The capabilities of this new technology for imaging of the interior of the large intestine were tested in pre-clinical experiments showing potential for improvement in margin verification during minimally invasive endoscopic treatment in the telemanipulation mode.
... iSCAN 2 is a combination of SE and tone enhancement (TE) technologies and is suggested for lesion characterization. iSCAN 3 comprises SE, CE, and TE and is recommended for lesion delineation [33,34] (Figure 2). Linked color imaging (LCI, Fujifilm, Japan) has been developed as a new pre-process image-enhanced endoscopy which differentiates the red color spectrum better than white-light imaging, making lesions more reddish and the nearby mucosa more whitish, thus achieving an improved contrast for identifying colonic alterations [35,36]. ...
... Narrow-band imaging (NBI, Olympus, Tokyo, Japan) was introduced in 2005. It is a blue-light technology that improves visualization of superficial mucosal structures, particularly superficial microvessels, by filtering the illumination light to wavelengths which are absorbed by hemoglobin [32,33]. Flexible spectral imaging color enhancement (FICE, Fujifilm, Tokyo, Japan) is a post-processor application which enhances vascularization and colonic mucosa images. ...
... Flexible spectral imaging color enhancement (FICE, Fujifilm, Tokyo, Japan) is a post-processor application which enhances vascularization and colonic mucosa images. This technology chooses only specific wavelengths from the white-light image and reconstructs a composite color-enhanced image [33]. Also, iSCAN (Pentax, Tokyo, Japan) is a post-processing image enhancement technology that produces digital contrast for a more defined mucosal pattern and vascularization. ...
Article
Full-text available
Subjects affected by ulcerative colitis and Crohn’s disease with colonic localization have an increased risk of colorectal cancer (CRC). Surveillance colonoscopy is recommended by international guidelines as it can detect early-stage CRC. Based on previous evidence, in 2015 the Surveillance for Colorectal Endoscopic Neoplasia Detection and Management in Inflammatory Bowel Disease Patients International Consensus indicated dye chromoendoscopy (DCE) as the most effective technique for detecting dysplasia. However, advances in endoscopic technology such as high-definition colonoscopes and dye-less virtual chromoendoscopy (VCE) may change future practice. In this review, we summarize the available evidence on CRC surveillance in IBD, focusing on the emerging role of high-definition white light endoscopy (HD-WLE) and VCE over the standard DCE, and the current role of random biopsies.
... The first case of flexible gastrointestinal (GI) endoscopy was performed in the 1960s (East et al., 2016), then advances in endoscopic technology have continued with high resolutions. Conventional white light endoscopy is the current standard for evaluating the mucosa of the GI tract due to accessibility, short endoscopic time, and low cost. ...
... Narrow-band illumination is absorbed by hemoglobin, and the shortened wavelength penetrates the surface tissue. This technique results in enhanced contrast of superficial microvessels and mucosal surface (East et al., 2016). Magnifying narrow-band imaging (M-NBI) has widespread use in Asian countries but not in Western countries. ...
... The information on three colors (RBG) is used unlike the technique of WLI. The output of LCI provides the image with color enhancement in its range, enhancing the differences of mucosal color and helping to detect sufficient brightness (East et al., 2016). ...
Article
Helicobacter pylori infection is a class I carcinogen that can lead to gastric cancer. Early diagnosis and eradication of H. pylori infection are important to eliminate the risk of gastric cancer. Several invasive diagnostic techniques require biopsy samples, resulting in avoidable injury and medical expense. Furthermore, due to the localized distribution of H. pylori, random biopsies are not always reliable in diagnosing H. pylori infection. This article aimed to review endoscopic findings and new endoscopic options for the diagnosis of H. pylori infection. Using conventional white light imaging (WLI) and image-enhanced endoscopy (IEE), the endoscopic features associated with histological changes have increasingly become apparent. Real-time endoscopy is essential to make a diagnosis of H. pylori infection and allow targeted biopsy. Image-enhanced endoscopy (IEE), such as narrow-band imaging (NBI), linked color imaging (LCI), and blue laser imaging (BLI), enhances visualization of the surface vascular pattern and provides accurate diagnostic performance in H. pylori infection, as well as gastric neoplastic lesions, compared to conventional white light endoscopy. In conclusion, the new endoscopic technologies could be used in current practice with conventional white light endoscopy for accurate and real-time diagnosis of H. pylori infection and pre-cancerous lesions.
... 3,9 In CRC, the depth of SMI can be determined using image-enhanced endoscopy, magnifying endoscopy, and/or endoscopic ultrasonography (EUS). 2,10 Among the image-enhanced endoscopy methods, the most widely used is narrow-band imaging (NBI). 10 Most of the classifications in which colorectal lesions are evaluated by NBI (Sano, Hiroshima, Showa, Japan NBI Expert Team classification [JNET]) include magnification. ...
... 2,10 Among the image-enhanced endoscopy methods, the most widely used is narrow-band imaging (NBI). 10 Most of the classifications in which colorectal lesions are evaluated by NBI (Sano, Hiroshima, Showa, Japan NBI Expert Team classification [JNET]) include magnification. However, as the use of magnified endoscopes is limited in Western countries, the use of these classifications has been very limited. ...
... The NICE classification is widely used in Western countries as it does not require magnification. 10,14,15,22,23 However, the NICE classification has four disadvantages: first, the lack of differentiation between serrated and hyperplastic polyps in the NICE type 1 classification. 24 The present study did not include the NICE type 1 lesions. ...
Article
Full-text available
Abstract Objective: There are limited data on the applicability of the narrow-band imaging (NBI) International Colorectal Endoscopic (NICE) classification for colorec- tal lesions larger than 10 mm. The purpose of the present study was to evaluate the correlation between the NICE classification and histopathology of colorectal lesions larger than 10 mm resected using endoscopic submucosal dissection (ESD). Methods: The present single-center retrospective study screened patients who underwent ESD between August 2019 and December 2020. The study included colorectal lesions that were larger than 10 mm and considered as NICE type 2 or type 3 in NBI examination. The correlation between the NICE classification and histopathology was the primary endpoint. Results: In total, 64 colorectal lesions were included. There were 54 lesions in the NICE type 2 group and 10 lesions in the NICE type 3 group. The en bloc resection rate with ESD was 100%, and the R0 resection rate was 96%. Submucosal fibrosis was more common in the NICE type 3 group. The procedure du- rations were similar in both groups. Histopathological correlation was better in the NICE type 2 group. The submucosal invasion rate was higher in the NICE type 3 group (P < .05). Conclusion: The NICE classification may be insufficient for diagnosis of deep submucosal invasive colorectal lesions larger than 10 mm. Diagnostic ESD can be safely applied in some colorectal lesions considered as NICE type 3. Keywords: Endoscopic submucosal dissection, histopathology, narrow-band imaging international colorectal endoscopic classification
... On the other hand, the clinical impact of this curriculum and ways to analyze its implementation are topics for future research. Similarly, the role of AEI in the upper GI tract has also been extensively explored [15]. There are ESGE standards that have already been set around the use of AEI [16]. ...
... There is a need for standardization of patterns and evaluation of the diagnostic yield of AEI in less experienced hands, but it is clear that NBI and BLI increase the accuracy of endoscopic diagnosis and should be used by trained endoscopists using validated classifications, as suggested in the ESGE guidelines [4,15]. ...
Article
Background One of the aims of the European Society of Gastrointestinal Endoscopy (ESGE) is to encourage high quality endoscopic research at a European level. In 2016, the ESGE research committee published a set of research priorities. As endoscopic research is flourishing, we aimed to review the literature and determine whether endoscopic research over the last 4 years had managed to address any of our previously published priorities. Methods As the previously published priorities were grouped under seven different domains, a working party with at least two European experts was created for each domain to review all the priorities under that domain. A structured review form was developed to standardize the review process. The group conducted an extensive literature search relevant to each of the priorities and then graded the priorities into three categories: (1) no longer a priority (well-designed trial, incorporated in national/international guidelines or adopted in routine clinical practice); (2) remains a priority (i. e. the above criterion was not met); (3) redefine the existing priority (i. e. the priority was too vague with the research question not clearly defined). Results The previous ESGE research priorities document published in 2016 had 26 research priorities under seven domains. Our review of these priorities has resulted in seven priorities being removed from the list, one priority being partially removed, another seven being redefined to make them more precise, with eleven priorities remaining unchanged. This is a reflection of a rapid surge in endoscopic research, resulting in 27 % of research questions having already been answered and another 27 % requiring redefinition. Conclusions Our extensive review process has led to the removal of seven research priorities from the previous (2016) list, leaving 19 research priorities that have been redefined to make them more precise and relevant for researchers and funding bodies to target.
... • Всем пациентам, у которых впервые проводится диагностическая ЭГДС, для адекватного стадирования предраковых состояний слизистой оболочки желудка у пациентов с подозрением на наличие атрофических, метапластических и неопластических изменений рекомендуется проведение биопсии (с последующим патолого-анатомическим исследованием биопсийного материала желудка, в том числе с применением гистохимических и иммуногистохимических методов), как для диагностики инфекции H. pylori, так и для идентификации стадий атрофического гастрита [52][53][54][55][56][57][58][59]. ...
... Дополнительная биопсия должна быть взята из каждого видимого патологического участка слизистой оболочки желудка. Если для оценки тяжести атрофического гастрита планируется использование систем OLGA или OLGIM, возможно дополнительное взятие биопсии из угла желудка [52][53][54][55][56][57]. ...
Article
Aim. The clinical guidelines are intended to supplement specialty decision-making for improved aid quality in patients with gastritis and duodenitis though acknowledging the latest clinical evidence and principles of evidencebased medicine. Key points. Gastritis is an inflammatory disease of stomach mucosa, with a separate definition of acute and chronic gastritis. Chronic gastritis is a cohort of chronic diseases uniting a typical morphology of persistent inflammatory infiltration, impaired cellular renewal with emergent intestinal metaplasia, atrophy and epithelial dysplasia of gastric mucosa. Oesophagogastroduodenoscopy (OGDS) or high-resolution OGDS with magnified or non-magnified virtual chromoendoscopy, including targeted biopsy for atrophy and intestinal metaplasia grading and neoplasia detection, are recommended to verify gastritis and duodenitis, precancer states and/or gastric mucosal changes. All chronic gastritis patients positive for H. рylori should undergo eradication therapy as aetiological and subsidiary for gastric cancer prevention. Chronic gastritis patients with symptoms of dyspepsia (epigastric pain, burning and congestion, early satiety), also combined with functional dyspepsia, are recommended proton pump inhibitors, prokinetics, rebamipide and bismuth tripotassium dicitrate in symptomatic treatment. With focal restricted intestinal metaplasia, follow-up is not required in most cases, mainly when advanced atrophic gastritis is ruled out in high-quality endoscopy with biopsy. However, a familial history of gastric cancer, incomplete intestinal metaplasia and persistent H. pylori infection render endoscopy monitoring with chromoendoscopy and targeted biopsy desirable once in three years. Patients with advanced atrophic gastritis should have high-quality endoscopy every 3 years, and once in 1–2 years if complicated with a familial history of gastric cancer. Conclusion. The recommendations condense current knowledge on the aetiology and pathogenesis of gastritis and duodenitis, as well as laboratory and instrumental diagnostic techniques, main approaches to aetiological H. pylori eradication and treatment of dyspeptic states.
... Gastrointestinal endoscopy procedures are separated into esophagoscopy, gastroscopy, duodenoscopy, colonoscopy and small bowel endoscopy [29]. ...
... Some video processors provide, in combination with distinct light sources, enhancement technologies like narrow band imaging (NBI), autofluorescence (AF) or flexible spectral imaging color enhancement (FICE). Using a selected wavelength for illumination and filtering the acquired image can improve the visibility of fine structures, details, or distinct lesions [29,[37][38][39][40][41][42]. Linked color imaging (LCI) and blue laser imaging (BLI) are image enhancement technologies using narrow band light. ...
Article
Full-text available
One of the most applied imaging methods in medicine is endoscopy. A highly specialized image modality has been developed since the first modern endoscope, the “Lichtleiter” of Bozzini was introduced in the early 19th century. Multiple medical disciplines use endoscopy for diagnostics or to visualize and support therapeutic procedures. Therefore, the shapes, functionalities, handling concepts, and the integrated and surrounding technology of endoscopic systems were adapted to meet these dedicated medical application requirements. This survey gives an overview of modern endoscopic technology’s state of the art. Therefore, the portfolio of several manufacturers with commercially available products on the market was screened and summarized. Additionally, some trends for upcoming developments were collected.
... Alarmingly, lower detection rates are associated with higher risk for interval CRC (1)(2)(3)(4). Intuitively the remedy to colonoscopy's imperfection is to improve detection and this prevailing narrative has driven the development and evolution of multiple technologies such that the major colonoscope manufacturers all currently produce high definition (HD) imaging systems with one or more integrated detection technologies (Olympus, Fujfilm and Pentax, Tokyo, Japan) (5). New colonoscope systems have even been developed specifically around new detection technology such as widening field of view (FUSE EndoChoice Inc., Alpharetta, GA, USA) (6). ...
... In contrast to NBI, which uses optical light filters, FICE is an image processing technique to select particular wavelengths from an image which is then reconstructed. Similar to NBI, data from the red light bandwidth can be discarded and the image can be created with a narrowed spectrum of green and blue light (5). In 2014, a systematic review and metaanalysis was published which reported no greater yield of adenomas with FICE when compared to HD-WLE (RR 1.09; 95% CI: 0.97-1.23) ...
Article
The detection and removal of polyps at colonoscopy is core to the current colorectal cancer (CRC) prevention strategy. However, colonoscopy is flawed with a well described miss rate and variability in detection rates associated with incomplete protection from CRC. Consequently, there is significant interest in techniques and technologies which increase polyp detection with the aim to remedy colonoscopy's ills. Technologic advances in colonoscope imaging are numerous and include; increased definition of imaging, widening field of view, virtual technologies to supplant conventional chromocolonoscopy (CC) and now computer assisted detection. However, despite nearly two decades of technologic advances, data on gains in detection from individual technologies have been modest at best and heterogenous and conflicted as a rule. This state of detection technology science is exacerbated by use of relatively blunt metrics of improvement without consensus, the myopic search for gains over single generations of technology improvement and an unhealthy focus on adenomatous lesions. Yet there remains cause for optimism as detection gains from new technology, while small, may still improve CRC prevention. The technologies are also readily available in current generation colonoscopes and have roles beyond simply detection such as lesion characterization, further improving their worth. Coupled with the imminent expansion of computer assisted detection the detection future from colonoscope imaging advances looks bright. This review aims to cover the major imaging advances and evidence for improvement in polyp detection.
... Despite considerable technical developments in endoscopic practice, including magnified endoscopy (ME) with narrowband imaging (NBI), the gastric cancer missed rate remains as high as 10%. 2 Furthermore, considerable interobserver differences in the characterization of lesions identified during gastroscopy have been reported. 3 To solve this problem, artificial intelligence (AI) and computer-aided diagnosis (CAD) could constitute an additional technical tool to assist and support physicians. In the past decade, AI, especially with a deep learning approach, has made tremendous progress in the identification and characterization of neoplasia in the GI tract. ...
... Although several different types of endoscopy are currently used to observe and study gastric mucosal lesions (13), an accurate pathological diagnosis is still required as the gold standard in verifying the specificity and accuracy of endoscopy. Because the image fields acquired by various types of endoscopes in vivo are small, it is difficult to make the preoperative endoscopy findings and postoperative mucosal lesions on ESD specimens have accurate "point-to-point" correspondence, which leads to a rough process and inaccurate conclusion during the comparison between the pathological diagnosis in vitro and gastroscopic diagnosis in vivo (14). ...
Article
Full-text available
Objective: It is always challenging to diagnose and characterize early gastric cancer surrounded by non-cancerous mucosa, including the malignant diagnosis and extent and depth of the lesions. Therefore, we developed a light transmission-assisted pathological examination to diagnose and characterize early gastric cancer. Here, we performed a parallel comparison between the light transmission-assisted pathological examination under endoscopy and the histological examination for the diagnosis of early gastric cancer. Methods: First, the endoscopic submucosal dissection (ESD) specimen was first placed on the surface of the light-emitting diode lamp to observe the mucosal surface structure and blood vessels. Second, the sliced and embedded tissue strips were cut into 3-µm sections for hematoxylin and eosin staining. Third, the histopathology of each section was projected onto a macroscopic image. Finally, the macroscopic and microscopic changes in the ESD specimens observed under endoscopy were compared. Seventy cases of early gastric adenocarcinoma were diagnosed and characterized using this new method. Results: Using the conventional pathological method, the demarcation line of the lesions was seen in 40 of 70 (57.1%) cases. Furthermore, no surface structure or microvascular changes were observed in any of the cases. Based on the light transmission-assisted pathological examination, 58 of 70 (82.9%) cases presented clear edges of neoplastic and non-neoplastic epithelia, with a classifiable surface structure (88.6%) and microvascular type (78.8%). Conclusions: This pilot method provided a practical bridge between endoscopic and pathological examinations. Compared to the histological examination, the light transmission-assisted pathological examination was an easier and more precise way to match the in vivo endoscopic observation and in vitro pathological examination.
... Application of the narrow band light source is an effective solution to enhance the contrast of non-invasive blood vessel imaging [16,17]. The central wavelength λc of the light source bandwidth should be chosen according to the hemoglobin spectral absorption maxima. ...
... The performances reported by the majority of the AI/ML-based models surpass both the NPV threshold recommended by the American Society of Gastrointestinal Endoscopy (90%) for adenoma detection and the estimated pooled NPV reported in a meta-analysis conducted by the society (91%) [82,83]. Finally, we should mention that currently, the majority of the CAD systems that we reported have the shortcoming of manual segmentations of lesions. ...
Article
Artificial intelligence (AI) is an umbrella term used to describe a cluster of interrelated fields. Machine learning (ML) refers to a model that learns from past data to predict future data. Medicine and particularly gastroenterology and hepatology, are data-rich fields with extensive data repositories, and therefore fruitful ground for AI/ML-based software applications. In this study, we comprehensively review the current applications of AI/ML-based models in these fields and the opportunities that arise from their application. Specifically, we refer to the applications of AI/ML-based models in prevention, diagnosis, management, and prognosis of gastrointestinal bleeding, inflammatory bowel diseases, gastrointestinal premalignant and malignant lesions, other nonmalignant gastrointestinal lesions and diseases, hepatitis B and C infection, chronic liver diseases, hepatocellular carcinoma, cholangiocarcinoma, and primary sclerosing cholangitis. At the same time, we identify the major challenges that restrain the widespread use of these models in healthcare in an effort to explore ways to overcome them. Notably, we elaborate on the concerns regarding intrinsic biases, data protection, cybersecurity, intellectual property, liability, ethical challenges, and transparency. Even at a slower pace than anticipated, AI is infiltrating the healthcare industry. AI in healthcare will become a reality, and every physician will have to engage with it by necessity. © The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
... However, their consequent implementation in the clinical routine is rare. [27][28][29][30] Identification of hyperplastic polyps enables "resect-and-discard" ...
Article
Full-text available
Background Artificial intelligence (AI) using deep learning methods for polyp detection (CADe) and characterization (CADx) is on the verge of clinical application. CADe already implied its potential use in randomized controlled trials. Further efforts are needed to take CADx to the next level of development. Aim This work aims to give an overview of the current status of AI in colonoscopy, without going into too much technical detail. Methods A literature search to identify important studies exploring the use of AI in colonoscopy was performed. Results This review focuses on AI performance in screening colonoscopy summarizing the first prospective trials for CADe, the state of research in CADx as well as current limitations of those systems and legal issues.
... However, current classifications do not include serrated polyps which are often difficult to differentiate from hyperplastic or adenomatous ones. Consequently, the Workgroup serrAted polypS and Polyposis (WASP) classification was developed that improved the endoscopic diagnosis of serous polyps, but more studies are still needed to prove its effectiveness [31][32][33]. The use of standardized scales improves diagnostic accuracy and significantly reduces interobserver variability. ...
Article
Full-text available
Introduction: Amongst all malignant tumors, cancers of the digestive tract rank first in terms of yearly deaths. Patients above 60 years of age are the most affected, as the diagnosis is frequently made in advanced stages of the disease when therapy is less effective. Our study aimed to evaluate the efficiency of narrow-band imaging (NBI) endoscopy and probe-based confocal laser endomicroscopy (pCLE) in the correct diagnosis of preneoplastic lesions in the upper and lower digestive tract. Patients, materials and methods: We included 46 patients with digestive preneoplastic lesions, who underwent either upper or lower digestive endoscopy, followed by NBI and pCLE. We recorded 5-10 frames per each lesion, from different angles and distances during white-light endoscopy and selected frames from full recordings of NBI and pCLE. Usual preparation was used for the endoscopic procedures; pCLE required in vivo administration of 10% Sodium Fluorescein as a contrast agent. Pathology was performed in case of solid tumors. Three medical professionals with different levels of training, blinded to the results, interpreted the data. Results: The experienced physician correlated very well the NBI findings with pathology (0.93, p=0.05), while the resident physician and the experienced nurse obtain lower, albeit still statistically significant, values (0.73 and 0.62, respectively). For pCLE, the experienced physician obtained near-perfect correlation with pathology (0.96), followed closely by the resident physician (0.93). The nurse obtained a modest correlation (0.42). All examiners obtained approximately equal performances in discerning between malignant and benign lesions. Conclusions: Digestive endoscopy in NBI mode proved its effectiveness. Even less experienced endoscopists can achieve good results, while an experienced nurse can positively influence the diagnosis. In the case of pCLE, when available, it can greatly reduce diagnostic times, while requiring higher expertise and specialty training.
... As the first equipment-based IEE, 25 NBI represented revolutionary progress in endoscopy technology. It abandoned the red component from conventional red-green-blue light filters and only allowed light frequencies that matched the absorption spectrum of hemoglobin (415 nm) to pass through the endoscope and hit the tissuethat is, the 415 nm blue light for highlighting the capillaries in the superficial mucosa and the 540 nm green light for penetrating deeper into the mucosa. ...
Article
An accumulating body of evidence has shown that detection and resection of pre-cancerous adenoma by colonoscopy could effectively prevent colorectal cancer (CRC) and its related mortality. Among various colonoscopy quality indicators, such as cecal intubation rate, withdrawal time, and adenoma detection rate (ADR), ADR is the most important one and most closely associated with the subsequent risk of CRC. Image-enhanced endoscopy (IEE), including digital and dye-based IEE, was originally developed to discriminate neoplastic from non-neoplastic lesions but later studies have demonstrated that it can also enhance lesion detection by enhancing the contrast between the lesion and background colonic mucosa. Nevertheless, using IEE in colonoscopy for lesion detection is still not the standard way of practice in the real world. For a better understanding of current IEE modalities, this review introduces and compared the currently available IEE modalities and their efficacy in detecting adenoma from the results of randomized controlled trials or meta-analyses.
... Computerbased training could be periodically reinforced relatively easily. The ESGE suggest the most likely scenario will be as a "second reader" as opposed to a "stand alone" system [32]. Therefore, for AI to be utilized in everyday practice there is a need for endoscopists to up skill in optical diagnosis to be able to safely interpret and act upon the readings from AI systems. ...
Article
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Background and study aims Correct optical diagnosis of colorectal polyps is crucial to implement a resect and discard strategy. Training methods have been proposed to reach recommended optical diagnosis thresholds. The aim of our study was to present a systematic review and meta-analysis on optical diagnosis training. Methods PubMed/Medline and Cochrane databases were searched between 1980 and October 2019 for studies reporting outcomes on optical diagnosis training of colorectal polyps. The primary outcome was optical diagnosis accuracy compared to histological analysis pre-training and post-training intervention. Subgroup analyses of experienced/trainee endoscopists, training methods, and small/diminutive polyps were included. Results Overall, 16 studies met inclusion criteria, analyzing the impact of training on 179 endoscopists. Pre-training accuracy was 70.3 % (6416/9131 correct diagnoses) whereas post-training accuracy was 81.6 % (7416/9213 correct diagnoses) (risk ratio [RR] 1.17; 95 % confidence interval [CI]: 1.09–1.24, P < 0.001). In experienced endoscopists, accuracy improved from 69.8 % (3771/5403 correct diagnoses) to 82.4 % (4521/5485 correct diagnoses) (RR 1.20; 95 % CI: 1.11–1.29, P < 0.001). Among trainees, accuracy improved from 69.6 % (2645/3803 correct diagnoses) to 78.8 % (2995/3803 correct diagnoses) (RR 1.14; 95 % CI 1.06–1.24, P < 0.001). In the small/diminutive polyp subgroup, accuracy improved from 68.1 % (3549/5214 correct diagnoses) to 77.1 % (4022/5214 correct diagnoses) in (RR 1.16 95 % CI 1.08–1.24 P < 0.001). On meta-regression analysis, the improvement in accuracy did not differ between computerized vs. didactic training approaches for experienced (P = 0.792) and trainee endoscopists (P = 0.312). Conclusions Optical diagnosis training is effective in improving accuracy of histology prediction in colorectal polyps. Didactic and computer-based training show comparable effectiveness in improving diagnostic accuracy.
... Therefore, an endoscopy method with large depth (500 µm) is highly desirable for the treatment decision making [1,2]. As an "optical biopsy" tool, confocal endomicroscopy has been applied for early diagnostics in gastric cancer owing to its superior subcellular resolution [5,6]. Traditional confocal endomicroscopy technique requires mechanical Z-scan to achieve depth-resolved imaging and it requires fluorescent label for imaging [7,8]. ...
Article
Current endoscopy techniques have difficulties to provide both high resolution and large imaging depth, which significantly hinders the early diagnosis of gastric cancer. Here, we developed a label-free, large-depth, three-dimensional (3D) chromatic reflectance confocal endomicroscopy. In order to solve the problem of insufficient imaging depth of traditional chromatic confocal microscopy, a customized miniature objective lens both with large chromatic focal shift and correction for spherical aberration was used to focus light of different wavelengths at different depths of the sample simultaneously, and a fiber bundle containing 50000 single-mode cores was used to collect the confocal reflectance signal. To acquire detailed information along the axial direction at a faster speed, a high-speed multi-pixel spectrometer was used to realize simultaneous detection of multi-depth signals. Specifically, we have built up a label-free fiber-optic 3D chromatic reflectance confocal endomicroscopy, with 2.3 µm lateral resolution, imaging depth of 570 µm in 3D phantom and 220 µm in tissue, and 1.5 Hz 3D volumetric frame rate. We have demonstrated that the fiber-optic 3D chromatic confocal endomicroscopy can be used to image human gastric tissues ex vivo, and provide important morphological information for diagnosis without labeling. These results show the great potential of the fiber-optic 3D chromatic confocal endomicroscopy for gastric cancer diagnosis.
... Image-enhanced endoscopy (IEE) is designed to enhance mucosal characteristics and improve diagnostic yield of endoscopy for various diseases of the digestive tract [9,10]. Autofluorescence imaging (AFI) displays the extent of histological mucosal atrophy in the gastric corpus as a greenish color, with sensitivity of 72 % and specificity of 78 % [11]. ...
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Background and study aims The aim of this study was to elucidate the differences in image-enhanced endoscopy (IEE) findings between Helicobacter-pylori-associated and autoimmune gastritis. Patients and methods Seven H. pylori-naïve, 21 patients with H. pylori-associated gastritis and seven with autoimmune gastritis were enrolled. Mucosal atrophy in the corpus was evaluated using autofluorescence imaging and classified into small, medium and large. In a 2 × 2-cm area of the lesser curvature of the lower corpus, micromucosal pattern was evaluated by magnifying narrow band imaging and proportion of foveola (FV)- and groove (GR)-type mucosa was classified into FV > 80 %, FV 50 % to 80 %, GR 50 % to 80 %, and GR > 80 %, then a biopsy specimen was taken. Results Fifteen of 21 (71 %) H. pylori-associated gastritis patients exhibited medium-to-large atrophic mucosa at the corpus lesser curvature. All autoimmune gastritis patients had large atrophic mucosa throughout the corpus (P < 0.001). All H. pylori-naïve patients had the FV > 80 % micromucosal pattern. Nineteen of 21 (90 %) H. pylori-associated gastritis patients had varying proportions of GR- and FV-type mucosae and five of seven (71 %) autoimmune gastritis patients showed FV > 80 % mucosa (P < 0.001). Compared with patients who were H. pylori-naïve, patients with H. pylori-associated and autoimmune gastritis exhibited a higher grade of atrophy (P < 0.001), but only patients with H. pylori-associated gastritis showed a higher grade of intestinal metaplasia (P = 0.022). Large mucosal atrophy with FV > 80 % micromucosal pattern had sensitivity of 71 % (95 % CI: 29 %–96 %) and specificity of 100 % (95 % CI: 88 % to 100 %) for diagnosis of autoimmune gastritis. Conclusions IEE findings of the gastric corpus differed between H. pylori-associated and autoimmune gastritis, suggesting different pathogenesis of the two diseases.
... Population-based gastric cancer screening endoscopy programs in Japan for adults aged >50 years and in Korea for adults aged >40 years have resulted in the early detection of gastric cancer with a resultant significant decrease in mortality (5,6). Image enhanced endoscopic technology (IEE), also called advanced endoscopic imaging, which includes Narrow Band Imaging (NBI), Flexible Spectral Imaging Color Enhancement (FICE), blue laser imaging (BLI), probe based Confocal Laser Endomicroscopy (pCLE), improves detection of gastric intestinal metaplasia, dysplasia, and early gastric cancer (2,7,8). ...
Article
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In this review, we would like to focus on risk stratification and quality indicators of diagnostic upper gastrointestinal endoscopy in the detection and characterization of early gastric cancer. Preparation of the upper gastrointestinal tract with mucolytic agents or simethicone is often overlooked in the west, and this inexpensive step prior to endoscopy can greatly improve the quality of imaging of the upper digestive tract. Risk stratification based on epidemiological features including family history, Helicobacter pylori infection status, and tobacco smoking is often overlooked but may be useful to identify a subgroup of patients at higher risk of developing gastric cancer. Quality indicators of diagnostic upper gastrointestinal endoscopy are now well defined and include: minimal inspection time of 3 min, adequate photographic documentation of upper gastrointestinal landmarks, utilization of advanced endoscopic imaging technology including narrow band imaging and blue laser imaging to detect intestinal metaplasia and characterize early gastric cancer; and standardized biopsy protocols allow for histological evaluation of gastric mucosa and detection of atrophic gastritis and intestinal metaplasia. Finally, endoscopic and histologic classifications such as the Kimura–Takemoto Classification of atrophic gastritis and the OLGA–OLGIM classifications may help stratify patients at a higher risk of developing early gastric cancer.
... Probe-based CLE (pCLE) could get through the working channels of various standard endoscopes [3] . Therefore, we used laparoscopy combined with choledochoscopy to place the pCLE in the gallbladder cavity to obtain diagnosis of gallbladder polyps, to observe the morphology and structure of normal gallbladder mucosal cells, and to evaluate the risk of gallbladder malignancy without damaging the gallbladder. ...
Article
Background: In the last decade, confocal laser endomicroscopy (CLE) has emerged as a new endoscopic imaging modality for real-time in vivo histological examination at the microscopic level. CLE has been shown to be useful for distinguishing benign and malignant lesions and has been widely used in many digestive diseases. In our study, we used CLE for the first time to examine the morphology of cholesterol polyps as well as the different parts of normal gallbladder mucosa. Case summary: A 57-year-old woman was diagnosed by ultrasound with a polyp of 21 mm in the gallbladder wall. She consented to polyp removal by laparoscopic choledo-choscopy. During laparoscopic cholecystectomy combined with choledochoscopic polyp resection, CLE was used to observe the morphology of the polyp surface cells. The appearance of the mucosa and microvessels in various parts of the gallbladder were also observed under CLE. Through comparison between postoperative pathology and intraoperative CLE diagnosis, the reliability of intraoperative CLE diagnosis was confirmed. CLE is a reliable method to examine living cell pathology during cholecystectomy. Based on our practice, CLE should be prioritized in the diagnosis of gallbladder polyps. Conclusion: Compared with traditional histological examination, CLE has several advantages. We believe that CLE has great potential in this field.
... Use of traditional chromoendoscopy has proven to improve detection of lesions, especially those that are not polypoid. On the other hand, comparison between HD-WLE and virtual chromoendoscopy did not show significant differences either in the polyp detection rate (PDR) or in the adenoma detection rate (ADR), even if a recent meta-analysis showed a slight but marginal superiority of the latter [10][11][12]. In the last few years, new approaches have been proposed to improve ADR and other quality colonoscopy indicators, including: devices to be mounted on the instrument (e. g., Endocuff, Endorings); delayed-release capsules based on methylene blue (MB-MMX); systematic changes of posture in the retraction phase; double inspection of the right colon; use of the water-exchange technique; and use of artificial intelligence (AI) [10]. ...
Article
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Background and study aims Adenoma detection rate (ADR) is a well-accepted quality indicator of screening colonoscopy. In recent years, the added value of artificial intelligence (AI) has been demonstrated in terms of ADR and adenoma miss rate (AMR). To date, there are no studies evaluating the impact of AI on the performance of trainee endoscopists (TEs). This study aimed to assess whether AI might eliminate any difference in ADR or AMR between TEs and experienced endoscopists (EEs). Patients and methods We performed a prospective observational study in 45 subjects referred for screening colonoscopy. A same-day tandem examination was carried out for each patient by a TE with the AI assistance and subsequently by an EE unaware of the lesions detected by the TE. Besides ADR and AMR, we also calculated for each subgroup of endoscopists the adenoma per colonoscopy (APC), polyp detection rate (PDR), polyp per colonoscopy (PPC) and polyp miss rate (PMR). Subgroup analyses according to size, morphology, and site were also performed. Results ADR, APC, PDR, and PPC of AI-supported TEs were 38 %, 0.93, 62 %, 1.93, respectively. The corresponding parameters for EEs were 40 %, 1.07, 58 %, 2.22. No significant difference was found for each analysis between the two groups (P > 0.05). AMR and PMR for AI-assisted TEs were 12.5 % and 13 %, respectively. Sub-analyses did not show any significant difference (P > 0.05) between the two categories of operators. Conclusions In this single-center prospective study, the possible impact of AI on endoscopist quality training was demonstrated. In the future, this could result in better efficacy of screening colonoscopy by reducing the incidence of interval or missed cancers.
... The action of this filter is to eliminate all wavelengths except those from 415 nm in blue color and from 540 nm in green color, both correspond to the absorption spectrum of hemoglobin. This mechanism allows for greater contrast for superficial micro vessels which appear brown / black and in greater clarity of superficial mucosal structures 4 . In particular, the blue light, which has a lower penetration depth, improves the vision of the superficial capillary network, while the green light, which penetrates more deeply, highlights the submucosal vascular texture. ...
Article
Background: In this study, the authors evaluated the role of narrow band imaging endoscopy in the early detection of infiltration of the colon wall by flat and depressed lesions, highlighted during colonoscopy, to confirm the possibility of removal with Endoscopic Mucosal Resection (EMR). Methods: 67 patients (37 males and 30 females) with non-polypoid colorectal lesions were included in this study. The location of the lesions, the size and possible infiltration of the colon wall were performed with a colonoscopy with NBI. Lesions without massive invasion were treated with an EMR. Results: NBI was found to be a sensitive, specific, and accurate technique in assessing any infiltration of the colon wall. Endoscopic resection of the mucous membrane was successfully performed in 62 patients, it was not possible to perform it in 5 patients, due to the lack of dissection, and they underwent surgery. Conclusions: Non-polypoid colorectal lesions and early tumors can be treated with EMR. Certainly, early detection with Narrow Band Imaging endoscopy and subsequent endoscopic resection can reduce colorectal cancer mortality. Many studies have confirmed that these two methods have achieved important results comparable with surgical procedures. Key words: Endoscopic Mucosal Resection, Narrow Band Imaging, Therapy.
... 12 However, each endoscopist has a different understanding of those abstract theories. 19 As a result, the consistency of EGC diagnosis between endoscopists is poor when the existing theories of EGC diagnosis are applied to clinical practice. AI has been widely applied in medical imagebased disease determination and classification, and the development of AI systems for assisting the diagnosis of EGC has been an attractive research topic during the past decade. ...
Article
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Background: Prompt diagnosis of early gastric cancer (EGC) is crucial for improving patient survival. However, most previous computer-aided-diagnosis (CAD) systems did not concretize or explain diagnostic theories. We aimed to develop a logical anthropomorphic artificial intelligence (AI) diagnostic system named ENDOANGEL-LA (logical anthropomorphic) for EGCs under magnifying image enhanced endoscopy (M-IEE). Methods: We retrospectively collected data for 692 patients and 1897 images from Renmin Hospital of Wuhan University, Wuhan, China between Nov 15, 2016 and May 7, 2019. The images were randomly assigned to the training set and test set by patient with a ratio of about 4:1. ENDOANGEL-LA was developed based on feature extraction combining quantitative analysis, deep learning (DL), and machine learning (ML). 11 diagnostic feature indexes were integrated into seven ML models, and an optimal model was selected. The performance of ENDOANGEL-LA was evaluated and compared with endoscopists and sole DL models. The satisfaction of endoscopists on ENDOANGEL-LA and sole DL model was also compared. Findings: Random forest showed the best performance, and demarcation line and microstructures density were the most important feature indexes. The accuracy of ENDOANGEL-LA in images (88.76%) was significantly higher than that of sole DL model (82.77%, p = 0.034) and the novices (71.63%, p<0.001), and comparable to that of the experts (88.95%). The accuracy of ENDOANGEL-LA in videos (87.00%) was significantly higher than that of the sole DL model (68.00%, p<0.001), and comparable to that of the endoscopists (89.00%). The accuracy (87.45%, p<0.001) of novices with the assistance of ENDOANGEL-LA was significantly improved. The satisfaction of endoscopists on ENDOANGEL-LA was significantly higher than that of sole DL model. Interpretation: We established a logical anthropomorphic system (ENDOANGEL-LA) that can diagnose EGC under M-IEE with diagnostic theory concretization, high accuracy, and good explainability. It has the potential to increase interactivity between endoscopists and CADs, and improve trust and acceptability of endoscopists for CADs. Funding: This work was partly supported by a grant from the Hubei Province Major Science and Technology Innovation Project (2018-916-000-008) and the Fundamental Research Funds for the Central Universities (2042021kf0084).
... However, the image resolution of AFI is even lower than WLE, for frame averaging is utilized to increase the quality of the autofluorescence image, and the intensity-based contrast of AFI is often not sufficiently specific [60,61]. In addition, the quick movement of the endoscope distal tip leads to the degradation of the images as the frame averaging cannot keep pace [62]. ...
Article
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Endoscopic optical imaging technologies for the detection and evaluation of dysplasia and early cancer have made great strides in recent decades. With the capacity of in vivo early detection of subtle lesions, they allow modern endoscopists to provide accurate and effective optical diagnosis in real time. This review mainly analyzes the current status of clinically available endoscopic optical imaging techniques, with emphasis on the latest updates of existing techniques. We summarize current coverage of these technologies in major hospital departments such as gastroenterology, urology, gynecology, otolaryngology, pneumology, and laparoscopic surgery. In order to promote a broader understanding, we further cover the underlying principles of these technologies and analyze their performance. Moreover, we provide a brief overview of future perspectives in related technologies, such as computer-assisted diagnosis (CAD) algorithms dealing with exploring endoscopic video data. We believe all these efforts will benefit the healthcare of the community, help endoscopists improve the accuracy of diagnosis, and relieve patients’ suffering.
... This means that an AI, which is capable of reliably screening the colonoscopy biopsies, could considerably reduce the workload of a practicing pathologist 16,17 . Additionally, it is worth noting that the assistive effect of AI on pathology is not limited to the evaluation of slides but extends to the acquisition of the target tissue of interest during sampling in a clinical setting such as narrow-band imaging [18][19][20][21][22][23][24] . If combined with in-vivo endoscopic assessments, AI can effectively revolutionize and streamline current diagnostic workflows 1,25 . ...
Article
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Colorectal cancer is one of the most common cancers worldwide, accounting for an annual estimated 1.8 million incident cases. With the increasing number of colonoscopies being performed, colorectal biopsies make up a large proportion of any histopathology laboratory workload. We trained and validated a unique artificial intelligence (AI) deep learning model as an assistive tool to screen for colonic malignancies in colorectal specimens, in order to improve cancer detection and classification; enabling busy pathologists to focus on higher order decision-making tasks. The study cohort consists of Whole Slide Images (WSI) obtained from 294 colorectal specimens. Qritive's unique composite algorithm comprises both a deep learning model based on a Faster Region Based Convolutional Neural Network (Faster-RCNN) architecture for instance segmentation with a ResNet-101 feature extraction backbone that provides glandular segmentation, and a classical machine learning classifier. The initial training used pathologists' annotations on a cohort of 66,191 image tiles extracted from 39 WSIs. A subsequent application of a classical machine learning-based slide classifier sorted the WSIs into 'low risk' (benign, inflammation) and 'high risk' (dysplasia, malignancy) categories. We further trained the composite AI-model's performance on a larger cohort of 105 resections WSIs and then validated our findings on a cohort of 150 biopsies WSIs against the classifications of two independently blinded pathologists. We evaluated the area under the receiver-operator characteristic curve (AUC) and other performance metrics. The AI model achieved an AUC of 0.917 in the validation cohort, with excellent sensitivity (97.4%) in detection of high risk features of dysplasia and malignancy. We demonstrate an unique composite AI-model incorporating both a glandular segmentation deep learning model and a classical machine learning classifier, with excellent sensitivity in picking up high risk colorectal features. As such, AI plays a role as a potential screening tool in assisting busy pathologists by outlining the dysplastic and malignant glands. Artificial intelligence (AI) is rapidly revolutionizing the field of pathology 1,2. Founded on the specialty practice of interpreting expressed histomorphological changes in cellular or tissue structure caused by disease processes , pathology has maintained its clinical utility till today 3. The objective evaluation of histological slides by highly-trained pathologists remains the gold standard for cancer diagnosis 4. With ever increasing workloads on pathologists, this time-consuming and manpower intensive work has recently seen the advent of computational pathology 5 largely enabled by whole slide images (WSIs) which are digital counterparts of traditional glass slides and which have received selected FDA approval for primary clinical diagnosis 5,6. Through application of medical image analysis, machine learning and deep convolutional neural networks (CNN), artificial intelligence have been used to inspect WSIs and produce computer-aided diagnosis (CAD) of cancers 1,5,7-9. These CADs have demonstrated non-inferiority in the identification of malignancy compared to traditional means 8,10-12. While human pathologists can outperform such AI systems, they are subject to fatigue, time-constraints and observer bias in clinical settings. As such CNN has the additional benefit of unimpaired accuracy only subject to the operational capacity of its processing hardware. With ever-increasing workloads, the integration of artificial intelligence into the field of computational pathology is a growing necessity 8. With an annual estimated 1.8 million cancer cases and 900,000 cancer deaths globally it places significant strain on healthcare OPEN
... [83][84][85] La mayoría de los estudios se han centrado en M-NBI, aunque también existen investigaciones con otros sistemas de CE digital. [86][87][88] Todos ellos señalan que, estos sistemas, empleados con magnificación, mejoran la capacidad de identificar y delimitar los márgenes horizontales con una precisión diagnóstica por encima del 85-90% e identifica algunos signos que sugieren infiltración de la submucosa como la dilatación de los vasos o la presencia de vasos con diferentes calibres. 84,86,[88][89][90][91][92][93][94] En el publicado por Hu et al., 83 la sensibilidad y especificidad fueron del 86% y el 96% con M-NBI y del 56% y 79% con ILB. ...
Article
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Resumen Este documento de posicionamiento, auspiciado por la Asociación Española de Gastroenterología, la Sociedad Española de Endoscopia Digestiva y la Sociedad Española de Anatomía Patológica tiene como objetivo establecer recomendaciones para realizar una endoscopia digestiva (EDA) de calidad en la detección y vigilancia de lesiones precursoras de cáncer gástrico (LPCG) en poblaciones con incidencia baja, como la española. Para establecer la calidad de la evidencia y los niveles de recomendación se ha utilizado la metodología basada en el sistema GRADE (Grading of Recommendations Assessment, Development and Evaluation). Se obtuvo el consenso entre expertos mediante un método Delphi. El documento evalúa diferentes medidas para mejorar la calidad de la EDA en este contexto y hace recomendaciones de cómo evaluar y tratar las lesiones identificadas. Se recomienda que la EDA de vigilancia de LPCG sea realizada por endoscopistas con capacitación adecuada, administrando premedicación oral y uso de sedación. Para mejorar la identificación de LPCG se recomienda el uso de endoscopios de alta definición y cromoendoscopia convencional o digital y, para las biopsias, debe utilizarse el NBI para dirigirlas a las áreas más sospechosas de metaplasia intestinal. En cuanto a la evaluación de las lesiones visibles, el riesgo de invasión de la submucosa debe evaluarse con endoscopios de magnificación y reservar la ecoendoscopia para aquellas con sospecha de invasión profunda. En las lesiones susceptibles de resección endoscópica, la disección endoscópica submucosa se considera la técnica de elección.
... To date, AI tools can at least match or even exceed human performance for CRC detection and diagnosis [168]. CADe models may act as a "second observer" during colonoscopy procedures and become useful for junior endoscopists' training [71]. ...
Article
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The development of artificial intelligence (AI) algorithms has permeated the medical field with great success. The widespread use of AI technology in diagnosing and treating several types of cancer, especially colorectal cancer (CRC), is now attracting substantial attention. CRC, which represents the third most commonly diagnosed malignancy in both men and women, is considered a leading cause of cancer-related deaths globally. Our review herein aims to provide in-depth knowledge and analysis of the AI applications in CRC screening, diagnosis, and treatment based on current literature. We also explore the role of recent advances in AI systems regarding medical diagnosis and therapy, with several promising results. CRC is a highly preventable disease, and AI-assisted techniques in routine screening represent a pivotal step in declining incidence rates of this malignancy. So far, computer-aided detection and characterization systems have been developed to increase the detection rate of adenomas. Furthermore, CRC treatment enters a new era with robotic surgery and novel computer-assisted drug delivery techniques. At the same time, healthcare is rapidly moving toward precision or personalized medicine. Machine learning models have the potential to contribute to individual-based cancer care and transform the future of medicine.
Article
Background and aims: Gastric precancerous conditions, including gastric atrophy (GA) and intestinal metaplasia (IM), play an important role in the development of gastric cancer. Image-enhanced endoscopy (IEE) shows great potential in diagnosing gastric precancerous conditions and adenocarcinoma. In this study, a deep convolutional neural network (DCNN) system, named ENDOANGEL, was constructed to detect gastric precancerous conditions by IEE. Methods: Endoscopic images were retrospectively obtained from 5 hospitals in China for the development, validation, internal and external test of the system. Prospective consecutive patients receiving IEE were enrolled from January 13, 2020 to October 29, 2020 in Renmin Hospital of Wuhan University to assess in real time the applicability of the proposed computer-aided detection (CADe) system in clinical practice, and the performance of CADe was compared with that of endoscopists. Results: Six thousand two hundred fifty endoscopy images from 760 patients and 98 video clips from 77 individuals undergoing IEE were enrolled in this study. The diagnostic accuracy of GA was 0.901 (95% CI, 0.883-0.917) in the internal test set, 0.864 (95% CI, 0.842-0.884) in the multicenter external test set, and 0.878 (95% CI, 0.796-0.935) in the prospective video test set. The diagnostic accuracy of IM was 0.908 (95% CI, 0.889-0.924) in the internal test set, 0.859 (95% CI, 0.837-0.880) in the multicenter external test set, and 0.898 (95% CI, 0.820-0.950) in the prospective video test set. CADe achieved similar diagnostic accuracy to that of the experts for detecting GA (0.869 [95% CI, 0.790-0.927] vs 0.846 [95% CI, 0.808-0.879]; p=0.396) and IM (0.888 [95% CI, 0.812-0.941] vs 0.820 [95% CI, 0.780-0.855]; p=0.117), and it was superior to that of nonexperts for GA (0.750 [95% CI, 0.711-0.786]; p=0.008) and IM (0.736 [95% CI, 0.697-0.773]; p=0.028). Conclusions: CADe achieved high diagnostic accuracy in gastric precancerous conditions, which was similar to that of experts and superior to that of nonexperts. Thus, CADe has a wide application prospect in assisting to diagnose gastric precancerous conditions.
Article
Endocytoscopy provides an in-vivo visualization of nuclei and micro-vessels at the cellular level in real-time, facilitating so-called “optical biopsy” or “virtual histology” of colorectal polyps/neoplasms. This functionality is enabled by 520-fold magnification power with endocytoscopy and recent breakthroughs in artificial intelligence (AI) allowing a great advance in endocytoscopic imaging; interpretation of images is now fully supported by AI tool which outputs predictions of polyp histopathology during colonoscopy. The advantage of the use of AI during optical biopsy can be appreciated especially by non-expert endoscopists who to increase performance. This paper provides an overview of the latest evidence on colorectal polyp characterization with endocytoscopy combined with AI and identify the barriers to its widespread implementation.
Article
Резюме. Рак і передракова патологія шлунка представляють на сьогодні важливу проблему в медицині. Особливого значення надають виявленню додаткових факторів ризику розвитку раку шлунка. Результати поодиноких досліджень показали взаємозв’язок між розвитком атрофічного гастриту й захворюваннями щитоподібної залози. Мета дослідження – визначити особливості макро- і мікроструктури слизової оболонки шлунка за даними ендоскопічного дослідження з режимами збільшення і вузькосмугової візуалізації у хворих на хронічний атрофічний гастрит залежно від наявності структурних змін у щитоподібній залозі (ЩЗ). Матеріали і методи. 45 хворим на атрофічний гастрит проводили ендоскопічне обстеження шлунка за допомогою ендоскопа з високою роздільною здатністю й вузькоспектральною візуалізацією та ультразвукове дослідження щитоподібної залози, за результатами якого хворих поділили на наступні групи: перша група – хворі з наявністю вогнищевих змін у ЩЗ, друга – пацієнти з дифузними змінами ЩЗ, група порівняння – без патологічних змін ЩЗ. Проводили статистичний та кореляційний аналізи отриманих даних. Результати. Аналіз отриманих даних дозволив виявити збільшення поширеності еритематозних змін в шлунку, тенденцію до збільшення частоти і поширеності вузлувато-бугристого рельєфу в групі хворих із вогнищевими утвореннями у ЩЗ, збільшення частоти ерозій, виразок і геморагій у пацієнтів зі структурними змінами в ЩЗ, суттєве збільшення частоти дифузного поширення кишкової метаплазії (КМ) у шлунку в осіб із вогнищевими змінами в ЩЗ, порівняно з хворими з дифузними змінами структури ЩЗ, або без них; дисплазію слизової оболонки шлунка виявлено в середньому тільки у хворих із структурними змінами ЩЗ з тенденцією до збільшення частоти цієї ознаки у пацієнтів першої групи (p>0,05). Отримані відмінності підтвер­джено кореляційним аналізом. Висновки. У хворих на атрофічний гастрит, поєднаний із патологією ЩЗ (дифузного й вогнищевого характеру), виявлено суттєве збільшення частоти структурних змін слизової оболонки шлунка, в т. ч. передракового характеру, що підтверджено результатами кореляційного аналізу й свідчить про необхідність подальшого ретельного вивчення даної проблеми.
Article
Amyloidosis is classifiable as systemic, with amyloid deposition in organs throughout the body, or localized, involving only one organ. Amyloidosis localized in the intestinal tract is rare. This report describes three cases of localized AL amyloidosis in the intestinal tract and presents their clinical characteristics, endoscopic findings, and prognoses. All three cases were asymptomatic, and were found accidentally during endoscopy for closer examination after a positive fecal occult blood test. Endoscopic findings included patchy redness and meandering dilated vessels of the lesion. Using autofluorescence (AFI) endoscopy, the lesion of amyloid deposition was enhanced as bright green. We used fluorescence microscopy to observe unstained specimens obtained from an amyloid deposition site with excitation light. Autofluorescence was detected with the broad excitation wavelength at amyloid deposition lesion sites of the specimen. Results revealed that AL amyloid has autofluorescence that engenders its detection by AFI endoscopy as bright green. In none of the three cases was systemic amyloidosis or organ failure observed. The long-term course of all the cases was favorable.
Article
Introducción y objetivos: La caracterización y rendimiento diagnóstico de los pólipos gástricos por imagen de banda estrecha (NBI por sus siglas en inglés) no han sido estandarizadas, el objetivo del presente estudio fue correlacionar NBI con la histopatología de los pólipos gástricos y determinar su eficacia diagnóstica para predicción de los diferentes tipos de pólipos gástricos. Material y métodos: Estudio prospectivo en pacientes mayores de 18 años que asistieron a endoscopia superior por dispepsia, síntomas de enfermedad de reflujo gastroesofágico o estudio de escrutinio, durante el 01 de abril de 2019 al 10 de junio de 2020 se excluyeron los pacientes con diagnóstico de cáncer gástrico por el riesgo de siembra tumoral con aspecto de pólipo y los pólipos mayores a 20 mm por el alto riesgo de progresión neoplásica. Los pólipos fueron identificados con luz blanca seguidamente con la técnica de NBI y near focus se caracterizaron, las lesiones resecadas se enviaron a patología para su estudio. La eficacia diagnóstica fue calculada en términos de sensibilidad y especificidad. Resultados: 139 pólipos gástricos en 124 pacientes se analizaron, los patrones microvasculares observados por NBI fueron los que mejor se correlacionaron con los hallazgos histopatológicos de los pólipos gástricos, un patrón en panal de abeja (sensibilidad 94.7%, especificidad 98.0%) para los pólipos de las glándulas fúndicas, vascular denso (sensibilidad 94.4%, especificidad 96.1%) en la predicción de los pólipos hiperplásicos, red fina (sensibilidad 94.7%, especificidad del 97.5%) para los adenomas, la combinación de centro vascular y patrón ausente (sensibilidad 85.0%, especificidad 98.3%) para predecir cánceres gástricos tempranos. Conclusiones: Los patrones microvasculares observado por NBI tienen alta eficacia para la predicción histopatológica de los pólipos gástricos.
Article
Background Clinical implementation of the resect-and-discard strategy has been difficult because optical diagnosis is highly operator dependent. This prospective study aimed to evaluate a resect-and-discard strategy that is not operator dependent. Methods The study evaluated a resect-and-discard strategy that uses the anatomical polyp location to classify colonic polyps into non-neoplastic or low risk neoplastic. All rectosigmoid diminutive polyps were considered hyperplastic and all polyps located proximally to the sigmoid colon were considered neoplastic. Surveillance interval assignments based on these a priori assumptions were compared with those based on actual pathology results and on optical diagnosis. The primary outcome was ≥ 90 % agreement with pathology in surveillance interval assignment. Results 1117 patients undergoing complete colonoscopy were included and 482 (43.1 %) had at least one diminutive polyp. Surveillance interval agreement between the location-based strategy and pathological findings using the 2020 US Multi-Society Task Force guideline was 97.0 % (95 % confidence interval [CI] 0.96–0.98), surpassing the ≥ 90 % benchmark. Optical diagnoses using the NICE and Sano classifications reached 89.1 % and 90.01 % agreement, respectively (P < 0.001), and were inferior to the location-based strategy. The location-based resect-and-discard strategy allowed a 69.7 % (95 %CI 0.67–0.72) reduction in pathology examinations compared with 55.3 % (95 %CI 0.52–0.58; NICE and Sano) and 41.9 % (95 %CI 0.39–0.45; WASP) with optical diagnosis. Conclusion The location-based resect-and-discard strategy achieved very high surveillance interval agreement with pathology-based surveillance interval assignment, surpassing the ≥ 90 % benchmark and outperforming optical diagnosis in surveillance interval agreement and the number of pathology examinations avoided.
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Electronic (virtual) chromoendoscopy technologies have had an enormous impact on the early detection and characterization of upper and lower gastrointestinal neoplasia. This has led to an improvement in optical diagnosis of early neoplasia, and allowed more targeted biopsies and better prediction of the risk of invasive cancer. In this chapter, we review various techniques and discuss their clinical use, focusing on oesophageal neoplasia and colorectal polyps.
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Die metaplastische Barrett-Schleimhaut stellt eine prämaligne Läsion für die Entstehung eines Adenokarzinoms des Ösophagus dar. Neben der bioptischen Sicherung stehen neuere Verfahren der (virtuellen) Chromoendoskopie (Essigsäure, NBI, i-Scan, FICE u. a.) zur Verfügung, um intraepitheliale Neoplasien (IEN, Dysplasien) besser zu detektieren. In Abhängigkeit des Vorhandenseins von IEN wird eine Barrett-Schleimhaut entweder endoskopisch im Verlauf kontrolliert oder mittels endoskopischer Mukosaresektion (EMR), endoskopischer Submukosadissektion (ESD) bzw. Radiofrequenzablation (RFA) therapiert. In diesem Kapitel wird der Stellenwert diagnostischer und therapeutischer Verfahren diskutiert sowie praktische Handlungsanleitungen nach aktuellen Leitlinien vorgestellt.
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This position paper, sponsored by the Asociación Española de Gastroenterología [Spanish Association of Gastroenterology], the Sociedad Española de Endoscopia Digestiva [Spanish Gastrointestinal Endoscopy Society] y the Sociedad Española de Anatomía Patológica [Spanish Anatomical Pathology Society], aims to establish recommendations for performing an high quality upper gastrointestinal endoscopy for the screening of Gastric Cancer Precursor Lesions (GCPL) in low-incidence populations, such as the Spanish population. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates different measures to improve the quality of upper gastrointestinal endoscopy in this setting and makes recommendations on how to evaluate and treat the identified lesions. We recommend that upper gastrointestinal endoscopy for surveillance of GCPL should be performed by endoscopists with adequate training, administering oral premedication and use of sedation. To improve the identification of GCPL, we recommend the use of high definition endoscopes and conventional or digital chromoendoscopy and, for biopsies, NBI should be used to target the most suspicious areas of intestinal metaplasia. Regarding the evaluation of visible lesions, the risk of submucosal invasion should be evaluated with magnifying endoscopes and endoscopic ultrasound should be reserved for those with suspected deep invasion. In lesions amenable to endoscopic resection, submucosal endoscopic dissection is considered the technique of choice.
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Image-enhanced endoscopy is useful for diagnosing and identifying lesions in the gastrointestinal tract. Recently, image-enhanced endoscopy has become a breakthrough technology that has attracted significant attention. This image enhancing technology is available for capsule endoscopy, which is an effective tool for small intestinal lesions and has been applied in flexible spectral color enhancement technology and in contrast capsule like narrow-band imaging. In this field, most researchers focus on improving the visibility and detection of small intestinal lesions. This review summarizes previous studies on image-enhanced capsule endoscopy and aims to evaluate the efficacy of this technology.
Article
Background and Aims This study aimed to evaluate the accuracy and effectiveness of the convolutional neural network (CNN) in diagnosing gastric cancer and predicting the invasion depth of gastric cancer, and to compare the performance of the CNN with that of endoscopists. Methods PubMed, Embase, Web of Science, and gray literature were searched until July 23, 2021, for studies that assessed the diagnostic accuracy of CNN-assisted examinations for gastric cancer or the invasion depth of gastric cancer. Studies meeting inclusion criteria were included in the systematic review and meta-analysis. Results Seventeen studies comprising 51,446 images and 174 videos of 5539 patients were included. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR–), and area under the curve (AUC) of the CNN for diagnosing gastric cancer were 89% (95% confidence interval [CI], 85–93], 93% (95% CI, 88–97), 13.4 (95% CI, 7.3–25.5), 0.11 (95% CI, 0.07–0.17), and 0.94 (95% CI, 0.91–0.98), respectively. The performance of the CNN in diagnosing gastric cancer was not significantly different from that of expert endoscopists (0.95 vs 0.90, P > 0.05) and was better than that of overall endoscopists (experts and nonexperts) (0.95 vs 0.87, P < 0.05). The pooled sensitivity, specificity, LR+, LR–, and AUC of the CNN for predicting the invasion depth of gastric cancer were 82% (95% CI, 78–85), 90% (95% CI, 82–95), 8.4 (95% CI, 4.2–16.8), 0.20 (95% CI, 0.16–0.26), and 0.90 (95% CI, 0.87–0.93), respectively. Conclusions CNN is highly accurate in diagnosing gastric cancer and predicting the invasion depth of gastric cancer. The performance of the CNN in diagnosing gastric cancer is not significantly different from that of expert endoscopists. Studies of the real-time performance of CNN for gastric cancer diagnosis are needed to confirm these findings.
Article
Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, is a chronic immune-mediated inflammatory disease that primarily affects the gastrointestinal tract and is characterized by periods of activity and remission. The inflammatory activity of the disease involving the colon and rectum increases the risk of colorectal cancer (CRC) over the years. Although prevention strategies are evolving, regular surveillance for early detection of neoplasia as a secondary prevention strategy is paramount in the care of IBD patients. In this review article, we discuss the current evidence of the risks of developing CRC and evaluate the best available strategies for screening and surveillance, as well as future opportunities for cancer prevention.
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Background: Esophageal adenocarcinoma (EAC) is one of the main causes of cancer-related deaths worldwide and its incidence is rising. Barrett's esophagus (BE) can develop low- and high-grade dysplasia which can progress to EAC overtime. The golden standard to detect dysplastic BE (DBE) or EAC is surveillance with high-definition white-light endoscopy (HD-WLE) and random biopsies according to the Seattle protocol. However, this method is time-consuming and associated with a remarkable miss rate. Therefore, there is great need for the development of novel reliable techniques to optimize surveillance strategies and improve detection rates. Summary: Optical chromoendoscopy (OC) techniques like narrow-band imaging have shown improved detection of DBE and EAC compared to HD-WLE and random biopsies. Most recent OC techniques, including the iSCAN optical enhancement system and linked color imaging, showed improved characterization of DBE and EAC retrospectively. Fluorescence molecular endoscopy (FME) presented promising results to highlight DBE and EAC. Moreover, with the establishment of well-performing delineation computer-aided detection (CAD) algorithms and the first real-time CAD system for EAC, we expect clinical application of CAD in the near future. Key messages: Despite impressive progress made in the development of advanced endoscopic techniques, combined HD-WLE/OC followed by random biopsies remains the golden standard for BE surveillance. Surveillance depends on appropriate mucosal cleansing, sufficient inspection time, and competence of the performing gastroenterologist to improve detection of EAC. In addition, to facilitate the clinical implementation of advanced endoscopic techniques, multicenter prospective clinical studies are demanded for OC and FME. Meanwhile, further optimization of CAD algorithms, the education of gastroenterologists, and analysis of the interaction between the clinician and the computer should be performed.
Article
Artificial intelligence (AI) systems based on machine learning have evolved in the last few years with an increasing applicability in gastrointestinal endoscopy. Thanks to AI, an image (input) can be transformed into a clinical decision (output). Although AI systems have been initially studied to improve detection (CADe) and characterization of colorectal lesions (CADx), other indications are being currently investigated as detection of blind spots, scope guidance, or delineation/measurement of lesions. The objective of these review is to summarize the current evidence on applicability of AI systems in gastrointestinal endoscopy, highlight strengths and limitations of the technology and review regulatory and ethical aspects for its general implementation in gastrointestinal endoscopy.
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Objective: Linked color imaging (LCI) is a recently developed technique that emphasizes differences in mucosal color. This study aimed to develop an LCI classification based on the Narrow-band Imaging International Colorectal Endoscopic (NICE) classification to predict colorectal polyp histology and evaluate the classification's validity and performance in differentiating hyperplastic polyps from adenomas. Methods: A workshop involving six international experts from China and Japan with substantial experience with LCI developed the classification. Three experienced endoscope experts and seven trainees used the LCI image collection to make independent predictions about the histology of polyps, recording their degrees of confidence in those predictions before and after completing the LCI classification training programme. Results: Of the 50 polyps, 30 (60%) were adenomas. Before-training total diagnostic accuracy was 75.4% (95% CI: 71.4-79.1), but after-training accuracy was 85.2% (95% CI: 81.8-88.2) (p<0.0001). After training, both experts and trainee endoscopists were 87.3% accurate in their prediction of polyps. Polyp prediction using the colour criterion had the highest specificity and positive predictive value (PPV) whereas vessel prediction using the vessel criterion had the higher precision and negative predictive value (NPV) among the individual LCI criteria. After training, both the expert and trainee groups had high degrees of interobserver agreement. Conclusions: We developed and validated the first LCI classification for the endoscopic differentiation of adenomas and hyperplastic polyps. The LCI classification significantly improved the accuracy of the optical diagnosis of colorectal polyps.
Chapter
Upper gastrointestinal endoscopy is the most important test used to diagnose esophageal disease. Proper insertion of the endoscope is essential for accurate examination of the esophagus. However, due to coughing or the gag reflex, esophageal examinations can be difficult. Further, when a central ridge is present in the middle of the pyriform sinus, careful approach is necessary. Chromoendoscopy of the esophagus includes acetic acid chromoendoscopy for Barrett’s esophagus and lugol’s iodine chromoendoscopy for squamous cell carcinoma. In recent times, electronic chromoendoscopy is widely used. In this chapter, diagnosis and treatment of various esophageal diseases including esophagitis, Barrett’s esophagus, adenocarcinoma, squamous cell carcinoma, diverticulum, inlet patch, hiatal hernia, polyps, subepithelial lesions, and varix are discussed.
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The aim of photography in digestive endoscopy is to obtain adequate, relevant, and quality endoscopy pictures in order to record diagnosis and therapeutic findings. Photo documentation and video recording are mandatory for the following purposes: to provide a complete case record; as a quality measure of complete examination; to facilitate communication; as a useful teaching resource; and in some case to protect physician in medicolegal issue. Endoscopy is a procedure that allows the inspection of internal hollow organs. Gastrointestinal endoscopy is the examination of GI tract witch is performed for diagnosis and therapeutic purpose. In this chapter we describe the technical evolution of both digestive endoscopy and medical photography during the last 70 years, coming from fiberscopes to high-resolution endoscopes and from argentic photography to digital pictures. Nowadays photography is an integral part of digestive endoscopy in clinical practice.
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Many clinical studies on narrow-band imaging (NBI) magnifying endoscopy classifications advocated so far in Japan (Sano, Hiroshima, Showa, and Jikei classifications) have reported the usefulness of NBI magnifying endoscopy for qualitative and quantitative diagnosis of colorectal lesions. However, discussions at professional meetings have raised issues such as i) the presence of multiple terms for the same or similar findings, ii) the necessity of including surface patterns in magnifying endoscopic classifications, and iii) differences in the NBI findings in elevated and superficial lesions. To resolve these issues, the Japan NBI Expert Team (JNET) was constituted with the aim of establishing a universal NBI magnifying endoscopic classification for colorectal tumors (JNET classification) in 2011. Consensus was reached on this classification using the modified Delphi method, and this classification was proposed in June 2014. This article is protected by copyright. All rights reserved. The JNET classification consists of 4 categories of vessel and surface patterns, i.e., Types 1, 2A, 2B, and 3. Types 1, 2A, 2B, and 3 are correlated with the histopathological findings of hyperplastic polyp/sessile serrated polyp (SSP), low grade intramucosal neoplasia, high grade intramucosal neoplasia/shallow submucosal invasive cancer, and deep submucosal invasive cancer, respectively.
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The novel method of image-enhanced endoscopy (IEE) named blue laser imaging (BLI) can enhance the contrast of surface vessels using lasers for light illumination. BLI has two IEE modes: high contrast mode (BLI-contrast) for use with magnification, and bright mode (BLI-bright), which achieves a brighter image than BLI-contrast and yet maintains the enhanced visualization of vascular contrast that is expected for the detection of tumors from a far field of view. The aim of this study is to clarify the effect of BLI-bright with a far field of view compared to BLI-contrast and commonly available narrow-band imaging (NBI). Patients with neoplasia, including early cancer in the pharynx, esophagus, stomach, or colorectum, were recruited and underwent tandem endoscopy with BLI and NBI systems. Six sets of images of the lesions were captured with a changing observable distance from 3 to 40 mm. Individual sets of images taken from various observable distances were assessed for visibility among BLI-bright, BLI-contrast, and NBI modes. The brightness and contrast of these images were also analyzed quantitatively. Of 51 patients, 39 were assessed. Image analysis indicated that only BLI-bright maintained adequate brightness and contrast up to 40 mm and had significantly longer observable distances compared to the other methods. Furthermore, BLI-bright enhanced the visualization of serious lesions infiltrating into deeper layers, such as esophageal lamina propria or gastric submucosal cancers. BLI-bright will be a helpful tool for the far-field view with IEE in organs with wider internal spaces such as the stomach.
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Background and study aims: It has been proposed that the use of narrow-band imaging (NBI) for real-time histological assessment to determine postpolypectomy surveillance intervals is a cost-effective approach to the management of diminutive polyps. However, significant discrepancies in NBI performance have been observed among endoscopists; hence, professional societies recommend training, monitoring, and auditing. The aim of the present study was to evaluate the performance of real-time optical diagnosis for diminutive polyps after the inclusion of this approach in an internal quality assurance program, in order to assess its applicability in clinical practice Patients and methods: Four endoscopists attended periodic training sessions on NBI assessment of polyp histology before and during the study. Performance was audited and periodic feedback was provided. The accuracy of high-confidence NBI evaluation for polyps ≤ 5 mm in predicting surveillance intervals according to the European and US guidelines, and the negative predictive value (NPV) for adenoma in the rectosigmoid were calculated and compared with recommended thresholds (90 % agreement and 90 % NPV, respectively). Results: Overall, 284 outpatients (mean age 61.3 ± 18.2 years; 63 % males) were enrolled. A total of 656 polyps were detected, 465 of which (70.9 %) were diminutive (70.5 % adenomas). Sensitivity, specificity, positive and negative predictive values, and accuracy of high-confidence NBI predictions for adenoma in diminutive lesions were 95.3 %, 83.5 %, 93.5 %, 87.6 %, and 91.9 %, respectively. High-confidence characterization of diminutive polyps predicted the correct surveillance interval in 95.8 % and 93.3 % of cases according to European and American guidelines, respectively. NPV for adenoma in the rectosigmoid was 91.3 % Conclusions: For community settings in which endoscopists are adequately trained and performance is periodically audited, real-time optical diagnosis for diminutive polyps is sufficiently accurate to avoid postpolypectomy histological examination of resected lesions, or to leave rectosigmoid hyperplastic polyps in place. Trial registered at ClinicalTrials.gov (NCT02196402).
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Image-enhanced endoscopy (IEE) can differentiate neoplastic from non-neoplastic colorectal lesions through indirect analysis of pit patterns and microvascular architecture. We evaluated the accuracy of Flexible Spectral Imaging Color Enhancement (FICE) in differentiating neoplastic from non-neoplastic lesions and observer agreement in the analysis of capillary pattern of colorectal lesions. A prospective double-blind trial was conducted in two referral endoscopy centers. Vascular pattern was analyzed by IEE with magnification. Lesions were divided into two groups and examined separately by two experts. Examiners, blinded to each other's interpretations, switched groups and the lesions were reviewed. After 60 days, lesions were reevaluated. In total, 76 patients were referred to colonoscopy for colon cancer screening. Of 100 colorectal lesions, 88 were neoplastic (73 tubular adenomas, 10 tubulovillous adenomas, 1 villous adenoma, 2 serrated adenomas, 2 adenocarcinomas) and 12 were non-neoplastic (hyperplastic polyps). Mean diameter of the lesions was 6.7 mm. Examiners 1 and 2 had 95 % accuracy. The interobserver kappa coefficient was 0.80 and the intraobserver kappa coefficient was 0.88 for examiner 1 and 0.73 for examiner 2. IEE with magnification is effective for real-time predictive histological diagnosis of colorectal lesions, with inter- and intraobserver agreement ranging from good to excellent.
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Background and study aims: Lugol's chromoendoscopy provides excellent sensitivity for the detection of early esophageal squamous cell neoplasms (ESCN), but its specificity is suboptimal. An endoscopy technique for real-time histology is required to decrease the number of unnecessary biopsies. This study aimed to compare the ESCN diagnostic capability of probed-based confocal laser endomicroscopy (pCLE) and dual focus narrow-band imaging (dNBI) in Lugol's voiding lesions. Patients and methods: Patients with a history of head and neck cancer without dysphagia were recruited. Lugol's voiding lesions larger than 5 mm were sequentially characterized by dNBI and pCLE by two independent operators. Finally, all lesions larger than 5 mm were biopsied followed by histological analysis, which is considered to be the gold standard in cancer diagnosis. The primary outcomes were the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the accuracy of the two techniques. Results: In total, 44 patients were enrolled with a mean age of 60 years; 80 % were male. Twenty-one Lugol's voiding lesions larger than 5 mm were detected in 12 patients. Seven lesions (33 %) from four patients were histologically diagnosed as ESCNs (four with high grade dysplasia and three with low grade dysplasia). The other 14 lesions were histologically confirmed as non-neoplastic: active esophagitis, glycogenation with inflammation, acute ulcer, inlet patch, and unremarkable changes. The sensitivity, specificity, PPV, NPV, and accuracy of pCLE vs. dNBI were 83 % vs. 85 %, 92 % vs. 62 %, 83 % vs. 54 %, 92 % vs. 89 %, and 89 % vs. 70 %, respectively (NS). Conclusions: Asymptomatic patients with a history of head and neck cancer underwent Lugol's chromoendoscopy based ESCN surveillance. Further characterization of the Lugol's voiding lesions by advanced imaging showed that both pCLE and dNBI provided good sensitivity in diagnosing ESCN, and pCLE tended to provide higher specificity, PPV, and accuracy than dNBI. Perhaps the trend of lower specificity of dNBI in this study was possibly because of the interference from Lugol's stain on the interpretation of intrapapillary capillary loops (IPCLs). Further study is required to seek a significant difference in the performance of dNBI and pCLE in a larger group of patients.
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Recent developments in image-enhancement technology have enabled clear visualization of the microvascular structure of the esophageal mucosa. In particular, intrapapillary capillary loops (IPCLs) are observed as brown loops on magnification endoscopy with narrow-band imaging (NBI). IPCLs demonstrate characteristic morphological changes according to the structural irregularity of esophageal epithelium and cancer infiltration, summarized in the IPCL classification. In this review, the process from the first endoscopic description of IPCLs to the eventual development of the IPCL classification is described and discussed, particularly focusing on early stage squamous cell carcinoma of the esophagus.
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Background Confocal laser endomicroscopy (CLE) can provide in vivo subcellular resolution images of esophageal lesions. However, the learning curve in interpreting CLE images of precancerous or early-stage esophageal squamous cancer is unknown. The goal of this study is to evaluate the diagnostic accuracy and inter-observer agreement for differentiating esophageal lesions in CLE images among experienced and inexperienced observers and to assess the learning curve. Method After a short training, 8 experienced and 14 inexperienced endoscopists evaluated in sequence 4 sets of high-quality CLE images. Their diagnoses were corrected and discussed after each set. For each image, the diagnostic results, confidence in diagnosis, quality and time to evaluate were recorded. Results Overall, diagnostic accuracy was greater for the second, third, fourth set of images as compared with the initial set (odds ratio [OR] 2.01, 95% CI 1.22–3.31; 7.95, 3.74–16.87; and 6.45, 3.14–13.27), respectively, with no difference between the third and fourth sets in accuracy (p = 0.67). Previous experience affected the diagnostic accuracy only in the first set of images (OR 3.70, 1.87–7.29, p<0.001). Inter-observer agreement was higher for experienced than inexperienced endoscopists (0.732 vs. 0.666, p<0.01) Conclusion CLE is a promising technology that can be quickly learned after a short training period; previous experience is associated with diagnostic accuracy only at the initial stage of learning.
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Main recommendations: 1 ESGE suggests the routine use of high definition white-light endoscopy systems for detecting colorectal neoplasia in average risk populations (weak recommendation, moderate quality evidence). 2 ESGE recommends the routine use of high definition systems and pancolonic conventional or virtual (narrow band imaging [NBI], i-SCAN) chromoendoscopy in patients with known or suspected Lynch syndrome (strong recommendation, low quality evidence). 2b ESGE recommends the routine use of high definition systems and pancolonic conventional or virtual (NBI) chromoendoscopy in patients with known or suspected serrated polyposis syndrome (strong recommendation, low quality evidence). 3 ESGE recommends the routine use of 0.1 % methylene blue or 0.1 % - 0.5 % indigo carmine pancolonic chromoendoscopy with targeted biopsies for neoplasia surveillance in patients with long-standing colitis. In appropriately trained hands, in the situation of quiescent disease activity and adequate bowel preparation, nontargeted, four-quadrant biopsies can be abandoned (strong recommendation, high quality evidence). 4 ESGE suggests that virtual chromoendoscopy (NBI, FICE, i-SCAN) and conventional chromoendoscopy can be used, under strictly controlled conditions, for real-time optical diagnosis of diminutive (≤ 5 mm) colorectal polyps to replace histopathological diagnosis. The optical diagnosis has to be reported using validated scales, must be adequately photodocumented, and can be performed only by experienced endoscopists who are adequately trained and audited (weak recommendation, high quality evidence). 5 ESGE suggests the use of conventional or virtual (NBI) magnified chromoendoscopy to predict the risk of invasive cancer and deep submucosal invasion in lesions such as those with a depressed component (0-IIc according to the Paris classification) or nongranular or mixed-type laterally spreading tumors (weak recommendation, moderate quality evidence). Conclusion: Advanced imaging techniques will need to be applied in specific patient groups in routine clinical practice and to be taught in endoscopic training programs.
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Detection of premalignant lesions in the upper gastrointestinal tract may facilitate endoscopic treatment and improve survival. Despite technological advances in white light endoscopy, its ability to detect premalignant lesions remains limited. Early detection could be improved by using advanced endoscopic imaging techniques, such as magnification endoscopy, narrow band imaging, i-scanning, flexible spectral imaging color enhancement, autofluorescence imaging, and confocal laser endomicroscopy (CLE), as these techniques may increase the rate of detection of mucosal abnormalities and allow optical diagnosis. The present review focuses on advanced endoscopic imaging techniques based on the use of CLE for diagnosing premalignant lesions in Barrett esophagus and stomach.
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Celiac disease (CD) is an autoimmune disease of the small bowel induced by ingestion of wheat, rye and barley. Current guidelines indicate histological analysis on at least four duodenal biopsies as the only way to diagnose CD. These indications are based on the conception of the inability of standard endoscopy to make diagnosis of CD and/or to drive biopsy sampling. Over the last years, technology development of endoscopic devices has greatly ameliorated the accuracy of macroscopic evaluation of duodenal villous pattern, increasing the diagnostic power of endoscopy of CD. The aim of this paper is to review the new endoscopic tools and procedures proved to be useful in the diagnosis of CD, such as chromoendoscopy, Fujinon Intelligent Chromo Endoscopy, Narrow Band Imaging, Optical Coherence Tomography, Water-Immersion Technique, confocal laser endomicroscopy, high-resolution magnification endoscopy, capsule endoscopy and I-Scan technology.
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In this review, we will discuss the use of two optical biopsy modalities in inflammatory bowel disease (IBD). The two techniques reviewed here are confocal laser endomicroscopy and endocytoscopy. We will describe the technical performance of the procedure, discuss the clinical indications for optical biopsy in IBD, and highlight active research areas with respect to the pathogenesis of IBD. Clinical indications for optical biopsies in IBD include assessment of mucosal inflammation, dysplasia detection and evaluation of cell shedding for disease relapse. Research application in the area of barrier dysfunction will also be discussed.
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Abstract Aim. The aim of the article is to systematically review the current evidence on the diagnostic use of narrow band imaging (NBI), flexible spectral imaging color enhancement (FICE) and endoscopic image enhancement technology i-scan endoscopies for gastric precancerous and cancerous lesions. Materials and methods. Original manuscripts were searched in PubMed until October 2012. Pertinent data were collected and pooled diagnostic accuracy measures were estimated when possible. Results. In total, 38 studies were evaluated. Thirty-one studies were included for NBI and 7 studies for FICE assessment in this systematic review. No article was found meeting inclusion criteria for i-scan endoscopy. The most defined and evaluated outcomes were cancer-related (n = 26). Quality Assessment of Diagnostic Accuracy Studies score varied from 9 to 12 (out of 14). Only few studies assessed the interobserver reliability. On a patient level analysis, NBI's pooled sensitivity, specificity and diagnostic odds ratio were 0.67 (95% CI: 0.61-0.73), 0.81 (95% CI: 0.76-0.85) and 22.71 (95% CI: 12.53-41.1), respectively for diagnosing normal mucosa; 0.86 (95% CI: 0.82-0.90), 0.77 (95% CI: 0.73-0.80) and 17.01 (95% CI: 1.4-207.2) for intestinal metaplasia and 0.90 (95% CI: 0.84-0.94), 0.83 (95% CI: 0.80-0.86) and 47.61 (95% CI: 4.61-491.34) for dysplasia. Owing to the insufficient data and different definitions, we could not aggregate the results for FICE. Conclusion. Gastric pattern descriptions have been proposed for NBI and FICE studies by gathering all descriptions in one single description. The classification systems varied between studies, a single description of gastric mucosal features with HR - scopes or at least per technology - will have to be agreed on.
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We studied the reliability of the previously described ulcerative colitis endoscopic index of severity (UCEIS) and validated it with an independent cohort of investigators. We created a new library of 57 videos of flexible sigmoidoscopy and stratified them based on disease severity. Twenty-five investigators were randomly assigned each to assess 28 videos (which included 4 duplicates, to assess intra-observer reliability). Investigators were blinded to clinical details except for 2 of 4 duplicated videos (to assess the impact of knowledge of symptoms on assessment). Three descriptors ('vascular pattern', 'bleeding', 'erosions and ulcers') comprising the UCEIS were scored, with a visual analog scale (VAS) to assess overall severity. Intra- and inter-investigator agreement were characterized by κ statistic analysis; reliability ratios were used to compare VAS and UCEIS scores. There was a high level of correlation between UCEIS score and overall assessment of severity (correlation coefficient 0.93). Internal consistency (Cronbach κ analysis) was 0.86. Intra- and inter-investigator reliability ratios for UCEIS scores were 0.96 and 0.88, respectively. Intra-investigator agreement in determination of UCEIS score was good (κ=0.72), with individual descriptors ranging from κ=0.47 (for bleeding) to κ=0.87 (for vascular pattern). Inter-investigator agreement in determination of UCEIS scores was moderate (κ=0.50), with descriptors ranging from κ=0.48 (for bleeding) to 0.54 (for vascular pattern). Intra-investigator variability in determining UCEIS scores did not change appreciably when a video was presented with clinical details. The UCEIS and its components show satisfactory intra-and inter-investigator reliability. Among investigators, the UCEIS accounted for a median of 86% of the variability in overall severity evaluation on VAS when assessing the endoscopic severity of UC and unaffected by knowledge of clinical details.
Article
Many clinical studies on narrow-band imaging (NBI) have reported the usefulness of NBI magnifying endoscopy for qualitative and quantitative diagnosis of colorectal lesions in Japan. However, critical discussions have raised issues such as i) the presence of multiple terms for similar findings, ii) the necessity of taking into account surface patterns, and iii) differences in NBI findings between elevated (polypoid growth, PG) and superficial lesions (non-polypoid growth, NPG). The Japan NBI Expert Team (JNET) was constituted with the aim of establishing a universal NBI magnifying endoscopic classification of colorectal tumors (JNET classification) in 2011. To establish a universal NBI magnifying endoscopic classification of colorectal tumors, the JNET, consisting of 38 NBI expert members, was formed within the "Research Group of the National Cancer Center Research and Development Fund" (Yutaka Saito Group) in 2011. First, a working group was organized consisting of young but experienced researchers from six institutions in order to establish common evaluation criteria of the JNET classification. Consequently, normal/hyperplastic lesions were classified as type 1, low-grade adenomas as type 2A, high-grade adenomas as type 2B, and deep submucosal invasive cancers as type 3, and a magnifying NBI scale that took into account the vascular and surface patterns was created for both PG and NPG tumors. A web-based interpretation study was conducted by a JNET member in order to determine the NBI findings and diagnostic criteria to be used in the universal classification system in 2013. A JNET classification system was established based on the results of univariate/multivariate analyses using a modified Delphi method at a consensus meeting on June 6, 2014. The JNET classification consists of four categories of vessel and surface patterns, i.e., Types 1, 2A, 2B, and 3. Types 1, 2A, 2B, and 3 are correlated with the histopathological findings of hyperplastic polyp/sessile serrated polyp (SSA/P), low-grade intramucosal neoplasia, high-grade intramucosal neoplasia/superficial submucosal invasive cancer, and deep submucosal invasive cancer, respectively. At present, validation studies for the JNET classification have been proposed to be conducted.
Article
Background and aims: Narrow-band imaging (NBI) international colorectal endoscopic (NICE) classification has been validated for differentiating hyperplastic from adenomatous polyps. This classification system was based on NBI technology, leaving uncertainty on its applicability to other systems. The aim of this study was to assess accuracy and reliability of histological predictions for subcentimetric polyps by applying NICE classification to Fujinon spectral Imaging Color Enhancement (FICE) system. Methods: A video-library of 55-subcentimeter histologically verified polyps with FICE was prospectively created including polyps that fulfilled inclusion criteria (morphology, size, histology) in consecutive colonoscopies. Six endoscopists with experience in electronic chromoendoscopy independently reviewed the polyps images, scored the polyps as adenoma or hyperplastic, and assigned a level of confidence to the predictions; 20 videos were reassessed at 6 months. The diagnostic performances of the endoscopists was calculated combined and individually according to the histopathology of the polyps. A mixed-effect logistic regression model in which polyps were considered as random-effects and polyp histology, confidence level, readers as fixed-effect was used. Results were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Results: Of the 55 polyps (mean size 4.6 mm), 29 (53%) were adenomas and 26 (47%) hyperplastic. Across all the readers and observations, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the curve (AUC) were 77%, 75%, 88%, 75%, 77%, and 0.82, respectively. Individual rater accuracy ranged from 66% to 96%, being <90% in 5 out of 6 cases. Overall, 68.5% (226 of 330) of predictions were made with high confidence, although there was high variability (Fleiss kappa, 0.15; 95% CI, 0.08-0.22). Sensitivity, specificity, PPV, NPV, accuracy, and AUC for predictions made with high confidence were 81%, 80.5%, 80%, 77%, 82%, and 0.88, being significantly more accurate as compared with a low-confidence of diagnosis (OR, 2.4; 95% CI, 1.2-4.7). Regarding the performance of the individual NICE-criteria, the odds of adenoma detection were 3.4 (95% CI, 1.8-6.3) and 4.0 (95% CI, 2.1-7.5) by using surface and vessels pattern alone, as compared with the color criterion. Inter- and intra-raters agreement with the NICE was only moderate (inter-:Fleiss kappa, 0.51; 95% CI, 0.44-0.56; intra-: kappa, 0.40; 95% CI, 0.20-0.60). Conclusions: The application of NICE classification to FICE resulted in suboptimal accuracy and only moderate inter-observer agreement.
Article
Background and aims: Barrett's esophagus (BE) is considered the most important risk factor for development of esophageal adenocarcinoma. Confocal laser endomicroscopy (CLE) is a recently developed technique used to diagnose neoplasia in BE. This meta-analysis was performed to assess the accuracy of CLE for diagnosis of neoplasia in BE. Methods: We searched EMBASE, PubMed, Cochrane Library, and Web of Science to identify relevant studies for all articles published up to June 27, 2015 in English. The quality of included studies was assessed using QUADAS-2. Per-patient (PP) and per-lesion (PL) pooled sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) with 95% confidence intervals (CIs) were calculated. Results: In total, 14 studies were included in the final analysis, covering 789 patients with 4047 lesions. Seven studies were included in the PP analysis. Pooled sensitivity and specificity were 89% (95% CI: 0.82-0.94) and 83% (95% CI: 0.78-0.86), respectively. Ten studies were included in the PL analysis. Compared with the PP analysis, the corresponding pooled sensitivity declined to 77% (95% CI: 0.73-0.81) and specificity increased to 89% (95% CI: 0.87-0.90). Subgroup analysis showed that probe-based CLE (pCLE) was superior to endoscope-based CLE (eCLE) in pooled specificity [91.4% (95% CI: 89.7-92.9) vs. 86.1% (95% CI: 84.3-87.8)] and AUC for the sROC (0.885 vs. 0.762) CONCLUSION: CLE is a valid method to accurately differentiate neoplasms from non-neoplasms in BE. It can be applied to BE surveillance and early diagnosis of esophageal adenocarcinoma.
Article
Background & aims: Although several classification systems have been proposed for characterization of Barrett's esophagus (BE) surface patterns based on narrow-band imaging (NBI), none have been widely accepted. The Barrett's International NBI Group (BING) aimed to develop and validate a NBI classification system for identification of dysplasia and cancer in patients with BE. Methods: The BING working group, comprising NBI experts from USA, Europe, and Japan, met to develop a validated, consensus-driven NBI classification system for identifying dysplasia and cancer in BE. The group reviewed 60 NBI images of non-dysplastic BE, high-grade dysplasia, and esophageal adenocarcinoma (EAC) to characterize mucosal and vascular patterns visible by NBI; these features were used to develop the BING criteria. We then recruited adult patients undergoing surveillance or endoscopic treatment for BE at 4 institutions in the United States and Europe, obtaining high-quality NBI images and performing histologic analysis of biopsies. Experts individually reviewed 50 NBI images to validate the BING criteria, and then evaluated 120 additional NBI images (not previously viewed) to determine whether the criteria accurately predicting the histology results. Results: The BING criteria identified patients with dysplasia with 85% overall accuracy, 80% sensitivity, 88% specificity, an 81% positive-predictive value, and an 88% negative-predictive value. When dysplasia was identified with a high level of confidence, these values were 92%, 91%, 93%, 89%, and 95%, respectively. The overall strength of inter-observer agreement was substantial (κ=.681). Conclusions: The BING working group developed a simple, internally validated system to identify dysplasia and EAC in patients with BE based on NBI results. When images are assessed with a high degree of confidence, the system can classify BE with greater than 90% accuracy and a high level of inter-observer agreement.
Article
Endoscopic assessment of mucosal healing in ulcerative colitis (UC) is increasingly accepted as a measure of disease activity, therapeutic goal, and the key prognostic indicator. While regular endoscopy evaluates appearance of the mucosal surface, confocal laser endomicroscopy (CLE) enables in vivo visualization of subepithelial mucosa at 1000× magnification during ongoing endoscopy. Our aims were to determine using CLE whether endoscopically normal appearing colonic mucosa in patients with UC in remission (UC-IR) has fully regenerated mucosal structures, resolved inflammation, and to identify the mechanisms. Twelve patients (six controls and six with UC-IR) underwent colonoscopy using CLE and intravenous fluorescein infusion. During colonoscopy, CLE images of colonic mucosa and conventional mucosal biopsies were obtained and evaluated using image-analysis systems. We quantified; (i) regeneration of colonic crypts and blood microvessels; (ii) cyclooxygenase 2 (COX2) expression; (iii) mitochondrial DNA (mtDNA) mutations; (iv) inflammatory infiltration; and (v) vascular permeability (VP). In control subjects, CLE demonstrated normal colonic crypts and microvasculature. COX2 expression was minimal, and < 7% crypts showed mtDNA mutations. Colonic mucosa of UC-IR patients had impaired and distorted crypt regeneration, increased COX2, 69% crypts with mtDNA mutations, persistent inflammation, and abnormal vascular architecture with increased VP (all P < 0.001 vs normal mucosa). (i) Endoscopically normal appearing colonic mucosa of patients with UC-IR remains abnormal: CLE demonstrates impaired crypt regeneration, persistent inflammation, distinct abnormalities in angioarchitecture and increased vascular permeability; molecular imaging showed increased COX2 and mtDNA mutations; (ii) CLE may serve as a new gold standard for the assessment of mucosal healing in UC. © 2015 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.
Article
Adenoma removal prevents colorectal cancer (CRC) development. Lower adenoma detection rates correlate with increased postcolonoscopy CRC. Chromoendoscopy it is not practical for routine use. It was hoped that electronic imaging techniques would offer effective alternatives to improve detection; however, meta-analyses in average-risk patients indicate no benefit. Narrow band imaging may be of benefit for high-risk surveillance. Combining electronic imaging techniques with molecular imaging probes may highlight dysplasia at a molecular level. In future colonoscopy is likely to rely on sensitive and specific, labeled molecular probes detected by electronic endoscopic imaging to enhance detection and reduce miss rates for premalignant lesions. Copyright © 2015 Elsevier Inc. All rights reserved.
Article
Background and study aims: A novel high definition colonoscopy imaging technique (i-Scan) can characterize, in detail, colonic mucosa in patients with ulcerative colitis, and may provide additional information about mucosal healing. The aim of this study was to create a more refined histological and endoscopic criteria based on this novel technique in order to redefine inflammatory activity and mucosal healing. Patients and methods: A total of 78 patients with ulcerative colitis were assessed by high definition colonoscopy as well as by white light endoscopy (WLE). Mayo endoscopic subscores were assigned to patients according to WLE findings. Mucosal and vascular patterns on high definition colonoscopy were each graded from 1 - 4. A histological scoring system (ECAP system) was designed to reflect all histological changes in ulcerative colitis. Results: The overall high definition imaging scores (mucosal and vascular patterns) were significantly correlated with Mayo endoscopic subscores (rs = 0.86, 95 % confidence interval [CI] 0.79 - 0.91; P < 0.0001). Of those with Mayo endoscopic subscore of 0, 30.4 % had an abnormal mucosal pattern and 73.9 % of them had an abnormal vascular pattern on high definition colonoscopy; a score of 6 or less had a sensitivity of 95.8 % (95 %CI 85.7 % - 99.3 %) and specificity of 75.9 % (95 %CI 56.5 % - 90.0 %) to detect mucosal healing as defined by Mayo endoscopy subscore of 0 or 1. Furthermore, mucosal and vascular pattern scores were also significantly correlated with most parameters of the proposed ECAP score. Conclusion: The subtle histological abnormalities underlying the apparently healed mucosa in ulcerative colitis could be detected using high definition colonoscopy and the refined ECAP histology scoring system. These techniques detect residual abnormalities in the majority of patients with seemingly complete mucosal healing by conventional Mayo criteria. © Georg Thieme Verlag KG Stuttgart · New York.
Article
Accurate endoscopic differentiation would enable to resect and discard small and diminutive colonic lesions, thereby increasing cost-efficiency. Current classification systems based on narrow band imaging (NBI), however, do not include neoplastic sessile serrated adenomas/polyps (SSA/Ps). We aimed to develop and validate a new classification system for endoscopic differentiation of adenomas, hyperplastic polyps and SSA/Ps <10 mm. We developed the Workgroup serrAted polypS and Polyposis (WASP) classification, combining the NBI International Colorectal Endoscopic classification and criteria for differentiation of SSA/Ps in a stepwise approach. Ten consultant gastroenterologists predicted polyp histology, including levels of confidence, based on the endoscopic aspect of 45 polyps, before and after participation in training in the WASP classification. After 6 months, the same endoscopists predicted polyp histology of a new set of 50 polyps, with a ratio of lesions comparable to daily practice. The accuracy of optical diagnosis was 0.63 (95% CI 0.54 to 0.71) at baseline, which improved to 0.79 (95% CI 0.72 to 0.86, p<0.001) after training. For polyps diagnosed with high confidence the accuracy was 0.73 (95% CI 0.64 to 0.82), which improved to 0.87 (95% CI 0.80 to 0.95, p<0.01). The accuracy of optical diagnosis after 6 months was 0.76 (95% CI 0.72 to 0.80), increasing to 0.84 (95% CI 0.81 to 0.88) considering high confidence diagnosis. The combined negative predictive value with high confidence of diminutive neoplastic lesions (adenomas and SSA/Ps together) was 0.91 (95% CI 0.83 to 0.96). We developed and validated the first integrative classification method for endoscopic differentiation of small and diminutive adenomas, hyperplastic polyps and SSA/Ps. In a still image evaluation setting, introduction of the WASP classification significantly improved the accuracy of optical diagnosis overall as well as SSA/P in particular, which proved to be sustainable after 6 months. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.