[Show abstract][Hide abstract] ABSTRACT: To determine if gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) cholangiography can detect and localize bile duct leaks in postcholecystectomy patients.
Four blinded independent radiologists performed a retrospective review of 16 consecutive patients who underwent MR cholangiography with intravenous Gd-EOB-DTPA for the evaluation of possible biliary leak. Image quality, ductal opacification, and presence and location of any bile leak were evaluated. An independent observer determined the criterion standard using a consensus of all chart, clinical, and imaging findings.
All 6 bile leaks confirmed at endoscopic retrograde cholangiopancreatography were diagnosed by all reviewers (sensitivity, 100%). Of the 10 patients with no leak, only one reader incorrectly diagnosed a bile leak in a single case (specificity, 98%). The accuracy for detection of the site of leak with Gd-EOB-DTPA-enhanced MR cholangiography was 80%.
Gadolinium-EOB-DTPA-enhanced MR can detect bile leaks with a high sensitivity and specificity.
Journal of computer assisted tomography 03/2014; · 1.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Both imaging and intervention play an increasingly important role in the management of renal masses in general and renal cancer in particular. Indeed, radiologists are often the first to detect and diagnose renal cancer, and now with the burgeoning role of percutaneous ablation, they are often the treating physicians. Renal mass management begins with imaging, and although most can be diagnosed with a high degree of certainty using imaging, some remain indeterminate and require biopsy or observation, now referred to as active surveillance. Although active surveillance strategies have been employed for indeterminate renal masses that have a reasonable chance of being benign, recent data suggest that some renal cancers can undergo active surveillance safely. This article reviews the current imaging-based diagnostic evaluation of incidentally detected small renal masses, the burgeoning role of percutaneous biopsy, and how both imaging and biopsy are used to help select which patients need treatment and which can undergo active surveillance.
Seminars in Interventional Radiology 03/2014; 31(1):9-19.
[Show abstract][Hide abstract] ABSTRACT: To determine whether a single 20 s breath-hold positron-emission tomography (PET) acquisition obtained during combined PET/computed tomography (CT)-guided percutaneous liver biopsy or ablation procedures has the potential to target 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG)-avid liver masses as accurately as up to 180 s breath-hold PET acquisitions.
This retrospective study included 10 adult patients with 13 liver masses who underwent FDG PET/CT-guided percutaneous biopsies (n = 5) or ablations (n = 5). PET was acquired as nine sequential 20 s, monitored, same-level breath-hold frames and CT was acquired in one monitored breath-hold. Twenty, 40, 60, and 180 s PET datasets were reconstructed. Two blinded readers marked tumour centres on randomized PET and CT datasets. Three-dimensional spatial localization differences between PET datasets and either 180 s PET or CT were analysed using multiple regression analyses. Statistical tests were two-sided and p < 0.05 was considered significant.
Targeting differences between 20 s PET and 180 s PET ranged from 0.7-20.3 mm (mean 5.3 ± 4.4 mm; median 4.3) and were not statistically different from 40 or 60 s PET (p = 0.74 and 0.91, respectively). Targeting differences between 20 s PET and CT ranged from 1.4-36 mm (mean 9.6 ± 7.1 mm; median 8.2 mm) and were not statistically different from 40, 60, or 180 s PET (p = 0.84, 0.77, and 0.35, respectively).
Single 20 s breath-hold PET acquisitions from PET/CT-guided percutaneous liver procedures have the potential to target FDG-avid liver masses with equivalent accuracy to 180 s summed, breath-hold PET acquisitions and may facilitate strategies that improve image registration and shorten procedure times.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this pictorial review is to discuss causes of female infertility, in particular, those etiologies in which imaging plays a key role in detection. Included are disorders of cervical, ovarian, fallopian tube, and uterine origin. We also discuss the role of various imaging modalities including hysterosalpingography, pelvic ultrasonography, hysterosonography, and pelvic MR imaging in elucidating the cause of female infertility. Radiologists need to know the conditions to be aware of when these patients are sent for diagnostic imaging, as well as how to direct further management, if necessary, should an abnormality be detected.
[Show abstract][Hide abstract] ABSTRACT: PURPOSE
To assess the use of CT in patients with acute pancreatitis (AP) presenting to the emergency department (ED).
METHOD AND MATERIALS
In this IRB-approved HIPAA-compliant retrospective study, we identified all patients with AP presenting from March 2012 through February 2013 to ED of an academic teaching hospital with approximately 60,000 annual visits. Patients were initially identified using ICD-9 code for AP (577.0) and diagnosis was then confirmed using clinical criteria from chart reviews. Based on existing literature, AP was confirmed when two of the following three were present: typical abdominal pain, elevated lipase/amylase >3 times normal and CT findings of pancreatitis. Abdominal CT scans obtained in ED or within 24 hours of admission were reviewed by a fellowship-trained abdominal radiologist.
Of total 103 patients diagnosed with AP (62 women; mean age 52 years, range 20-89), 90 (87.4%) could be diagnosed without CT based on abdominal pain and elevated labs; 13 (12.6%) required CT for diagnosis (Fig. 1). Abdominal CT was obtained in ED or within 24 hours of admission in total 65 (63.1%) patients. Of 90 patients in whom AP could be diagnosed based on clinical criteria alone, 52 (57.8%) underwent CT; of these, findings of AP were present in 36 (69.2%), sequela of a prior acute pancreatitis episode in one (1.9%) and normal CT in 15 (28.9%). None of the 65 patients who underwent CT showed presence of complications of pancreatitis (pancreatic/peripancreatic necrosis, peripancreatic ﬂuid collections, pseudocyst or walled-off necrosis, vascular complications, pleural effusion) or alternate explanation for patient's symptoms.
CT is frequently obtained in patients with AP presenting to ED even if diagnosis can be made based on established clinical criteria of typical abdominal pain and markedly elevated labs. CT is unlikely to be useful in these patients in the acute setting, as complications of AP in this setting may be rare.
Abdominal CT rarely shows complications of acute pancreatitis in the acute phase, and it may not be necessary if diagnosis can be confidently made based on typical abdominal pain and elevated labs.
Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
[Show abstract][Hide abstract] ABSTRACT: AIM: To determine how representative virtual unenhanced (VNE) images are of true unenhanced (TNE) images when performing computed tomography (CT) urography on a dual-energy CT (DECT) system, and whether the images are affected by the contrast material phase. MATERIALS AND METHODS: In this retrospective, institutional review board-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant study, TNE were compared with VNE images derived from the nephrographic (VNEn) and excretory (VNEe) phases in 100 consecutive CT urograms. Two readers in consensus measured attenuation values of abdominal organs, fat, and renal lesions (>1 cm). Image noise was correlated with patient thickness. Detectability of renal stones was evaluated. Image quality and acceptability was assessed using a five-point scale. Expected dose saving by removing the TNE phase was calculated. RESULTS: VNE attenuation values of liver, renal parenchyma, and aorta were significantly different to TNE values (p < 0.05); spleen and fat attenuation values showed no significant difference. No significant difference was found between VNEn and VNEe images. Image noise was significantly greater in TNE images (p < 0.0001) and correlated with patient thickness. VNEn and VNEe images had sensitivities of 76.6 and 65.6% for detection of stones, identifying all stones greater than 3 and 4 mm, respectively. Both VNE images received significantly lower image quality scores than TNE images (p < 0.0001); however, the majority of images were deemed acceptable. The mean theoretical dose saving by removing the TNE phase was 35%. CONCLUSION: Although VNE images demonstrate high reader acceptability, accuracy of attenuation values and detection of small stones is limited. The contrast material phase, however, does not affect attenuation values. Further validation of VNE images is recommended prior to clinical implementation.
[Show abstract][Hide abstract] ABSTRACT: Renal angiomyoadenomatous tumour is a rare, recently described neoplasm with a distinctive histological appearance. Although reported in the pathology literature, to our knowledge, no prior reports have described its imaging appearance. We describe the computed tomography and magnetic resonance imaging features of an incidentally detected renal angiomyoadenomatous tumour that appeared as a well-marginated, solid T2-hypointense enhancing mass, in a 50-year-old woman. It is indistinguishable from a variety of benign and malignant renal neoplasms.
Canadian Urological Association journal = Journal de l'Association des urologues du Canada 08/2012; 6(4):E140-3. · 1.66 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To describe the multidetector-row computed tomography enterographic (MD-CTE) features of the ileal-anal pouch after ileal pouch anal anastomosis (IPAA) surgery and correlate them with pouch endoscopy and histopathologic findings.
All MD-CTE examinations performed on patients who underwent IPAA from July 1, 2005 to December 1, 2010 (n = 35; 16 [45.7%] men; mean age, 37.7 years; age range, 22-72 years) were retrospectively evaluated in consensus by 2 radiologists. All studies were evaluated for the presence of multiple imaging features. Two radiographic scores were then calculated: a total radiographic score and a radiographic active inflammation score. In patients who underwent MD-CTE, pouch endoscopy, and biopsy within 30 days (n = 13), both scores were correlated with findings on pouch endoscopy and histopathology.
Of the 35 patients, 33 (94%) had at least one MD-CTE finding of active or chronic pouch inflammation and 27 patients (77%) had at least one MD-CTE finding of active pouch inflammation. Of the 13 patients who underwent endoscopy and biopsy, the total radiographic score demonstrated a strong positive correlation with endoscopic score (r = 0.81; P = 0.001) and a moderate positive correlation with histopathologic score (r = 0.56; P = 0.047). The radiographic active inflammation score demonstrated a strong positive correlation with endoscopic score (r = 0.83; P = 0.0004), but only a weak nonsignificant positive correlation with histopathologic score (r = 0.492, P = 0.087).
In patients who had IPAA surgery, findings on MD-CTE correlate positively with findings on pouch endoscopy and histopathology and are sensitive measures for pouch inflammation with high positive predictive value. Thus, MD-CTE can be a useful noninvasive test in the early evaluation of symptomatic patients.
[Show abstract][Hide abstract] ABSTRACT: Benign metastasizing pleomorphic adenoma is a rare condition that occurs in patients with a prior history of pleomorphic adenoma of the salivary glands. Metastases to the kidney are extremely rare, and, to the best of our knowledge, their imaging appearance on multiple cross-sectional imaging modalities has not been described. We present a solitary metastasis to the kidney in a 40-year-old woman. Computed tomography and magnetic resonance imaging demonstrated a 2.4 cm, well-marginated, enhancing mass that protruded into the renal sinus fat. Findings were indistinguishable from a primary renal malignancy. Prior history is crucial in suggesting the correct diagnosis.
[Show abstract][Hide abstract] ABSTRACT: This article describes the features on sonography, computed tomography (CT) and magnetic resonance imaging (MRI) of mucinous tubular and spindle cell carcinoma of the kidney. Six pathologically proven cases of mucinous tubular and spindle cell carcinoma of the kidney were identified (5 females, 1 male); all patients underwent preoperative imaging. The mean age of the patients was 58.5 years. Thirteen imaging studies were available for review: 2 sonograms, 1 unenhanced CT scan, 5 contrast-enhanced CT scans, 1 unenhanced magnetic resonance imaging (MRI) examination, and 4 contrast-enhanced MRI examinations. Two abdominal radiologists evaluated all images retrospectively on a PACS workstation using a standardized data collection sheet until consensus was reached. All mucinous tubular and spindle cell carcinomas presented as well-marginated, small (mean 2.6 cm, range 1.9-3.2 cm) predominantly solid masses. No intratumoral fat or calcification was identified. Unenhanced CT and MRI appearances were variable as was the degree of enhancement following intravenous contrast material administration. There was no evidence of perinephric extension, renal vein involvement or metastatic disease in any of the cases. The radiological appearance of mucinous tubular and spindle cell carcinoma is diverse and therefore indistinguishable from the more common subtypes of renal cell carcinoma.
Cancer Imaging 01/2012; 12:66-71. · 1.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study is to assess the feasibility of low-tube-voltage images during excretory phase CT urography.
In this retrospective study, we examined 70 consecutive CT urograms (35 men and 35 women; mean age, 58.5 years) performed on a dual-energy CT scanner and compared excretory phase images obtained at 80 kVp and 340 mAs with blended images (0.3 × 140 kVp and 80 mAs; and 0.7 × 80 kVp and 340 mAs). Quantitative measurements of urinary system opacification (Hounsfield units), image noise (Hounsfield units), and effective dose (millisieverts) were compared using Student paired t test. Image noise was correlated with patient thickness. Two independent blinded readers qualitatively assessed opacification, image quality (both compared using Wilcoxon test), overall acceptability (compared using McNemar test), and detectability of urinary and extraurinary findings.
The 80-kVp images yielded significantly higher opacification of renal pelvis (p < 0.0001), ureter (p < 0.0001), bladder (p < 0.0001), and aorta (p < 0.0001); higher image noise (p < 0.0001); and lower radiation dose (5.2 vs 11.9 mSv). Image noise increased along with increasing patient thickness (r = 0.86 for 80-kVp images). Qualitative opacification scores were better only in the bladder on 80-kVp images (p = 0.002). Although 80-kVp image quality was lower (p < 0.0001), the overall acceptability was similar. Of 42 urinary findings, 40 were detected on 80-kVp images (< 2-mm calyceal calculus and tiny foci of collecting system gas were missed in one patient each, both large patients). Of 137 extraurinary findings, 130 were detected on 80-kVp images (no findings of high clinical significance were missed).
Low tube voltage (80 kVp) during excretory phase CT urography is feasible, with improved urinary system opacification, acceptable image quality, and lower radiation dose.
American Journal of Roentgenology 11/2011; 197(5):1146-51. · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Evaluate the utility of multidetector-row computed tomography (MDCT) in assessing the severity of ulcerative colitis (UC) in comparison with clinical assessment, colonoscopy, and histopathology.
Patients with UC evaluated with at least one abdominal contrast-enhanced CT study (CECT) within 7 days of colonoscopy with biopsy were included. CECT of 23 patients (12 male; mean age 40 years; age range, 20-72 years) were retrospectively evaluated in consensus by two radiologists. A total of 138 lower GI tract segments were evaluated by CECT and graded for the presence of bowel wall thickening, mucosal hyperenhancement, mural stratification, mesenteric hyperemia, pericolonic stranding, and lymph nodes. A cumulative CT severity score was calculated and correlated with clinical, colonoscopic, and histopathologic severity grades.
The cumulative CT score and individual CECT scores for bowel wall thickening, mucosal hyperenhancement, and mural stratification showed positive correlation with clinical severity (P < 0.05). All individual CECT features as well as the cumulative CT score demonstrated statistically significant correlation with colonoscopic severity (P < 0.0001). Only wall thickening on CECT demonstrated significant correlation with histopathologic severity (P = 0.01).
Disease severity assessment by MDCT demonstrates positive correlation with severity established by clinical assessment and colonoscopy. Only increasing wall thickness, as graded on MDCT, correlates with histopathologic disease severity.
[Show abstract][Hide abstract] ABSTRACT: To determine the utility of 3.0-Tesla diffusion-weighted (DW) magnetic resonance imaging (MRI) for focal cystic pancreatic lesion (FCPL) characterization.
55 FCPL (34 IPMN, 5 serous cystadenoma, and 16 inflammatory) were evaluated. Two radiologists reviewed in consensus DW-MRI images. Reference standard was obtained from patient history, cytological and histopathology data, FCPL fluid analysis, and follow-up imaging results. Signal intensity (SI) and apparent diffusion coefficient values (ADC) of FCPL and normal pancreas were measured. FCPL-to-pancreas SI and ADC ratios were also calculated.
Qualitatively, 11 of 21 non-mucinous vs. 4 of 34 mucinous lesions appeared hyperintense at b value of 1,000 s/mm(2) (P = 0.02). Three FCPL demonstrated restricted diffusion: all inflammatory. Significant differences in mean ADC between neoplastic vs. non-neoplastic (P = 0.009), and mucinous vs. non-mucinous (P = 0.013) lesions were demonstrated. FCPL-to-pancreas ADC and SI ratios demonstrated significant differences between neoplastic vs. non-neoplastic lesions [ADC, (P = 0.019); SI for b values 750 (P = 0.010) and 1,000 s/mm(2) (P = 0.017)] and mucinous vs. non-mucinous lesions [ADC (P = 0.018); SI for b values 750 (P = 0.013) and 1,000 s/mm(2) (P = 0.015)].
Although mean ADC values and FCPL-to-pancreas SI and ADC ratios may be helpful in differentiating FCPL, characterization of individual FCPL by means of 3.0-Tesla DW-MRI appears limited.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to assess the usefulness of the defecation phase during dynamic MR defecography.
The images from 85 MR defecographic examinations (83 patients; age range, 20-88 years; mean, 52.7) were retrospectively reviewed in consensus by two observers. Images from each of four phases (rest, maximal sphincter contraction and squeezing, maximal straining, and defecation) were evaluated and scored independently with a modified previously published grading system. Features evaluated included the presence and degree of bladder, vaginal, and rectal descent and the presence and size of rectocele, enterocele, and intussusception. Statistical analysis was performed with a variety of tests.
Compared with images obtained in the other phases, defecation phase images helped in identification of additional cases of abnormal bladder descent in 43 examinations (50.6%), abnormal vaginal descent in 52 examinations (61.2%), and abnormal rectal descent in 11 examinations (12.9%). Similarly, only defecation phase images depicted previously undetected rectoceles 2 cm or larger in 31 examinations (36.5%), enteroceles in 34 examinations (40%), and intussusceptions in 22 examinations (25.9%). The number of additional cases of abnormalities identified on defecation phase images was significantly greater than the number identified on images obtained in the other phases (p < 0.005). The average total scores for the rest, squeeze, strain, and defecation phases were 1.4, 0.7, 2.3, and 6.6. The average total defecation phase score was significantly greater than the average total score in any of the other phases (p < 0.001).
During dynamic MR defecography, defecation phase imaging yields important additional information on the presence and degree of pelvic floor abnormalities and is therefore an essential component of MR defecographic examinations.
American Journal of Roentgenology 04/2011; 196(4):W394-9. · 2.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Traditional contrast-based radiographs of the bowel have now been replaced by more modern techniques based upon computerized
tomography, magnetic resonance, positron emission, and ultrasound-based imaging. Modern radiographic techniques have extended
beyond solely diagnostic purposes to monitoring of disease activity, progression, and response to therapeutic interventions.
The absence of ionizing radiation in MR imaging has been particularly attractive given the young population affected by inflammatory
bowel disease. MRI and endoanal ultrasound have increasingly replaced examination under anesthesia in the evaluation of perianal
Crohn’s disease, as well as monitoring therapeutic response to therapy. Noninvasive magnetic resonance cholangiography has
replaced endoscopic cholangiography to diagnose primary sclerosing cholangitis and its complications. Evolving future techniques
include MR colonography and positron emission tomography–CT (PET–CT).
KeywordsInflammatory bowel disease-Crohn’s disease-Ulcerative colitis-Computerized axial tomography-Magnetic resonance imaging-Multidetector-row CT-Endoanal ultrasound-Anal endosonography-Transcutaneous perianal ultrasound-Positron emission tomography-PET–CT-CT enterography-MR enterography-Examination under anesthesia-Endoscopic retrograde cholangiopancreatography-MR cholangiopancreatography
[Show abstract][Hide abstract] ABSTRACT: Percutaneous biopsy has long been used to diagnose malignancies of the kidney. It is an established technique with multiple indications. Percutaneous biopsy now can be used to diagnose benign conditions that may mimic a malignancy and lead to unnecessary treatments. Advances in cytological techniques such as immunocytochemistry and cytogenetics have allowed for an increased diagnostic yield. In this review, various benign entities that may present as a renal mass are discussed and the vital role of percutaneous biopsy detailed.
[Show abstract][Hide abstract] ABSTRACT: Patent vascular access is a prerequisite for adequate haemodialysis, and is a major determinant of quality of life and long-term survival of patients with end-stage renal disease. Autogenous haemodialysis fistulas (AVFs) have demonstrated superior clinical outcome when compared to synthetic grafts, but both types of access remain susceptible to venous stenoses, and consequent thrombotic occlusion. Recent publications have reported primary patency rates of up to 100% following percutaneous de-clotting of AVFs incorporating techniques such as pharmacological thrombolysis, mechanical thrombectomy, and thrombo-aspiration. Endovascular management also provides information regarding the underlying cause of access thrombosis, with option to treat. Consequently, there has been a paradigm shift in the management of fistula thrombosis, with interventional radiology assuming a lead role in initial salvage procedures. This article will attempt to provide the reader with an insight into the multiple radiological techniques that can be employed to salvage a thrombosed AVF based on current published literature.
[Show abstract][Hide abstract] ABSTRACT: The objective of this review article is to learn how to recognize anatomic variants and benign entities that mimic bladder cancer at computed tomography (CT) urography. Building on recent data that suggest that CT urography can be used to diagnose bladder cancer, recognition of anatomic variants and benign entities will help improve radiologists' ability to diagnose bladder cancer.
Cancer Imaging 01/2011; 11:100-8. · 1.59 Impact Factor