M Ortner

Inselspital, Universitätsspital Bern, Berna, Bern, Switzerland

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Publications (64)427.74 Total impact


  • No preview · Article · Aug 2015 · Zeitschrift für Gastroenterologie
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    ABSTRACT: Patients with long-standing ulcerative colitis require repeated endoscopies for early detection of neoplasias, which, however, are frequently missed by standard colonoscopy. Fluorescence-guided colonoscopy is known to improve the detection rate but the long-term effects of fluorescence-guided colonoscopy are unknown. Colitis patients with negative findings at index fluorescence-guided colonoscopy entered a prospective long-term study with conventional colonoscopies at 2-year intervals. Risk and time to progression were evaluated. The positive predictive value was assessed in patients with neoplasias at index fluorescence-guided colonoscopy who underwent immediate total colectomy. Thirty-one patients with negative fluorescence-guided colonoscopy were surveyed for a mean of 7.8 ± 0.9 years. Neoplasia was observed in only two of them (6%) after 7 and 8 years of follow-up, respectively. Neoplasia at index fluorescence-guided colonoscopy was observed in 10 patients. In all of them, multiple flat low-grade intraepithelial neoplasia was diagnosed. At immediate colectomy performed in eight of them, the diagnosis of flat low-grade intraepithelial neoplasia was confirmed, corresponding to a positive predictive value of 100%. However, synchronous more advanced neoplasia was detected in three of the eight patients (38%). All patients, those with and those without neoplasia, were alive at the end of the study. Fluorescence-guided colonoscopy misses, in contrast to standard colonoscopy, few, if any, patients with neoplasia. Most neoplasia-negative patients remain negative during prolonged follow-up. However, when low-grade dysplasia is diagnosed by fluorescence-guided colonoscopy, colectomy is recommended because more than a third of the patients harbor synchronous, more advanced neoplasia.
    Full-text · Article · Mar 2012 · Inflammatory Bowel Diseases
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    ABSTRACT: Low dose photodynamic therapy (LDPDT) may modify the mucosal immune response and may thus provide a therapy for Crohn's disease. We evaluated the efficacy and safety of this technique in a murine T cell-mediated colitis model. The safety of LDPDT was first tested in BALB/c mice. Naïve T cells were used to induce colitis in mice with severe combined immunodeficiency, which were followed up endoscopically, and a murine endoscopic index of colitis (MEIC) was developed. The efficacy of LDPDT (10 J/cm (2); delta-aminolevulinic acid, 15 mg/kg bodyweight) was then tested on mice with moderate colitis, while a disease control group received no treatment. The MEIC, weight, length, and histology of the colon, cytokine expression indices, number of mucosal CD4 (+) T cells, percentage of apoptotic CD4 (+) T cells, body weight, and systemic side effects were evaluated. LDPDT improved the MEIC ( P = 0.011) and the histological score ( P = 0.025), diminished the expression indices of the proinflammatory cytokines, interleukin-6 ( P = 0.042), interleukin-17 ( P = 0.029), and interferon-gamma ( P = 0.014), decreased the number of mucosal CD4 (+) T cells, and increased the percentage of apoptotic CD4 (+) T cells compared with the disease control group. No local or systemic side effects occurred. LDPDT improves murine T cell-mediated colitis, decreases the proinflammatory cytokines interleukin-6, interleukin-17, and interferon-gamma, and decreases the number of CD4 (+) T cells. No adverse events were observed. Therefore, this technique is now being evaluated in patients with inflammatory bowel disease.
    Full-text · Article · May 2011 · Endoscopy
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    ABSTRACT: Crohn's disease is an inflammatory bowel disease originating from an overwhelming response of the mucosal immune system. Low dose photodynamic therapy (PDT) may modify the mucosal immune response and thus serve as a therapy for Crohn's disease. Most patients with Crohn's disease show inflammatory reactions in the terminal ileum or colon where PDT treatment is feasible by low-invasive endoscopic techniques. However, the tube like geometry of the colon, it's folding, and the presences of multiple foci of Crohn's lesions along the colon require the development of adequate light delivery techniques. We present a prototype light delivery system for endoscopic clinical PDT in patients with Crohn's disease. The system is based on a cylindrical light diffuser inserted into a diffusing balloon catheter. Homogenous irradiation is performed with a 4 W diode laser at 635 nm. Light dosimetry is performed using a calibrated integrating sphere, The system can be used with conventional colonoscopes and colonovideoscopes having a 3.8 mm diameter working channel. The feasibility of PDT in colon with our prototype was demonstrated in first clinical trials. © 2007 SPIE-OSA.
    No preview · Article · Jun 2007 · Proceedings of SPIE - The International Society for Optical Engineering
  • Philippe Maerten · Marianne Ortner · Pierre Michetti · Gian Dorta
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    ABSTRACT: pH monitoring has been used as a diagnostic tool in gastro-oesophageal reflux disease (GERD) for many years. Recent studies have shown that wireless capsule pH monitoring is better tolerated and interferes less with daily activities as compared to traditional catheter-based pH monitoring. Moreover, prolonged recording time (48 h instead of 24 h) is possible with wireless pH monitoring. The main secondary effect of wireless capsule pH monitoring is induction of thoracic discomfort in 10-65% of the patients, which can vary from mild foreign body sensation to severe chest pain. Sensitivity and specificity of wireless capsule monitoring is comparable to that of traditional pH monitoring. It has not been proven yet that better tolerability and a longer recording time increases the diagnostic yield of wireless capsule monitoring in GERD.
    No preview · Article · Feb 2007 · Digestion

  • No preview · Article · Jan 2007
  • M A Ortner
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    ABSTRACT: Klatskin tumors are defined as malignant tumors of the bile duct involving the bifurcation and intrahepatic bile ducts. The most common presenting clinical feature, obstructive jaundice, usually occurs with advanced disease. Diagnostic tools currently available are therefore either performed too late or are not able to detect early disease stage. Imaging procedures for diagnosis and staging are ultrasonography, magnetic resonance imaging with cholangiopancreaticography, intravenous bolus-enhanced spiral computed tomography and endoscopic retrograde cholangiopancreaticography. Before initiating any palliative measure, a proper staging and a surgical consultation at a hepatobiliary center is necessary. To assess resectability, additional diagnostic methods like angiography, positron emission tomography, cholangioscopy, endoscopic or intraluminal ultrasonography and finally even explorative laparoscopy may be required. At time of diagnosis only a small percentage of Klatskin tumors is curative resectable. Therefore, palliative treatment options play an important role. Endoprostheses insertion is the method of choice to relieve jaundice. Although it improves quality of life, it does not seem to improve survival time. Definitive evidence for a benefit of additional radio and/or chemotherapy is still missing. Photodynamic therapy, a light therapy, is the first approach leading to an improvement of cholestasis and quality of life as well as to a prolongation of survival time. PDT should therefore be offered to all patients with nonresectable cholangiocarcinoma.
    No preview · Article · Nov 2006 · Praxis
  • M-A Ortner · G Dorta
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    ABSTRACT: Gastrointestinal bleeding is still one of the most frequent medical emergencies. Despite improvements in endoscopic diagnosis and therapy, mortality from bleeding is still high (15%). Since conclusive trials are lacking, the endoscopist often has to rely on personal experience in the selection of therapeutic options. Therefore this article gives an overview of new publications in this field and recommendations based on personal experience.
    No preview · Article · Mar 2006 · Der Chirurg
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    ABSTRACT: The aim of this review is to give an overview of palliative endoscopic treatment options in patients with advanced cancers of the esophagus, stomach, pancreas and bile ducts. With regard to esophageal cancers, we will also speak about curative endoscopic treatment (photodynamic therapy, mucosectomy) of early cancers and dysplasias. We will not approach to this subject in other types of carcinoma, since this has already been covered by the acquisitions of the last years.
    No preview · Article · Feb 2006 · Revue médicale suisse
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    ABSTRACT: The aim of this review is to give an overview of palliative endoscopic treatment options in patients with advanced cancers of the esophagus, stomach, pancreas and bile ducts. With regard to esophageal cancers, we will also speak about curative endoscopic treatment (photodynamic therapy, mucosectomy) of early cancers and dysplasias. We will not approach to this subject in other types of carcinoma, since this has already been covered by the acquisitions of the last years.
    No preview · Article · Jan 2006
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    ABSTRACT: In previous randomized trials, early endoscopy improved the outcome in patients with bleeding peptic ulcer, though most of these studies defined "early" as endoscopy performed within 24 hours after admission. Using the length of hospital stay as the primary criterion for the clinical outcome, we compared the results of endoscopy done immediately after admission (early endoscopy in the emergency room, EEE) with endoscopy postponed to a time within the first 24 hours after hospitalization, but still during normal working hours ("delayed" endoscopy in the endoscopy unit, DEU). We conducted a retrospective analysis of data from 81 consecutive patients with bleeding peptic ulcer admitted in 1997 and 1998 (age range 16 - 90 years). Of these 81 patients, 38 underwent DEU (the standard therapy at the hospital) and 43 underwent EEE. Patients in the two groups were comparable with regard to admission criteria, were equally distributed with respect to their risk of adverse outcome (assessed using the Baylor bleeding score and the Rockall score), and differed only in the treatment they received. Endoscopic hemostasis was performed whenever possible in all patients with Forrest types I, IIa, and IIb ulcer bleeding. We found similar rates in the two groups for recurrent bleeding (16 % in DEU patients vs. 14 % in EEE patients), persistent bleeding (8 % in DEU patients vs. none in EEE patients), medical complications (21 % in DEU patients vs. 26 % in EEE patients), the need for surgery (8 % in DEU patients vs. 9 % in EEE patients), and the length of hospital stay (5.1 days for DEU patients vs. 5.9 days for EEE patients). None of the differences between the two groups in these parameters were statistically significant. None of the patients died. Early endoscopy in an emergency room did not improve the clinical outcome in our 81 consecutive patients with bleeding peptic ulcer.
    No preview · Article · May 2005 · Endoscopy
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    ABSTRACT: Wireless capsule endoscopy (WCE) offers endoscopic access to the small bowel and may therefore change diagnostic and therapeutic strategies in small bowel diseases. The aim of this prospective study was to validate the gain in information and therapeutic impact of WCE in patients with Crohn's disease. Fifty six consecutive patients with Crohn's disease underwent computed tomography (CT) enteroclysis, and if stenoses <10 mm were excluded, WCE was carried out. In 15 patients (27%), WCE could not be performed due to strictures detected by CT enteroclysis. From the other 41 patients, jejunal or ileal lesions were found in 25 patients by WCE compared with 12 by CT enteroclysis (p=0.004). This gain in information was mainly due to detection of small mucosal lesions such as villous denudation, aphthoid ulcerations, or erosions. Both methods were not significantly different in the detection of lesions in the terminal/neoterminal ileum (WCE 24 patients, CT enteroclysis 20 patients). Therapy was changed due to WCE findings in 10 patients. Consecutively, all of them improved clinically. Capsule endoscopy improves the diagnosis of small bowel Crohn's disease. This may have significant therapeutic impact.
    Full-text · Article · Apr 2005 · Gut
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    ABSTRACT: The need is well recognized for additional data on endoluminal therapies for gastroesophageal reflux disease (GERD). This prospective multicenter clinical trial was designed to assess safety and effectiveness of Enteryx, a nonresorbable copolymer implanted into the lower esophagus, in reducing usage of proton pump inhibitors (PPIs) and improving reflux symptoms and quality of life. Enteryx implantation was performed under fluoroscopic visualization without general anesthesia in 93 patients with symptomatic GERD responsive to and relapsing upon cessation of PPI therapy. Subjective and objective data were collected up to 12 months postprocedure. The criterion for treatment success was reduction in PPI dosage of > or =50%. At 12 months, treatment success was attained in 86% (confidence interval, 77%-93%) of 74 evaluable patients and elimination of PPI therapy in 65% (confidence interval, 53%-76%). The treatment success rate by intent-to-treat analysis was 69% (confidence interval, 58%-78%). Reflux-related heartburn (P < 0.0001), regurgitation symptoms (P = 0.0005), and physical (P < 0.0001) and mental quality of life (P = 0.0012) scores improved. The most frequent complications were chest pain (77%), dysphagia/odynophagia (27%), and sensation of fever (26%). Enteryx implantation provides an effective and safe alternative for management of gastroesophageal reflux, reducing medication dependency and symptoms and enhancing quality of life.
    No preview · Article · Mar 2005 · Journal of Clinical Gastroenterology
  • H Messmann · C Ell · M Fein · R Kiesslich · M Ortner · R Porschen · M Stolte

    No preview · Article · Mar 2005 · Zeitschrift für Gastroenterologie
  • H Messmann · C Ell · M Fein · R Kiesslich · M Ortner · R Porschen · M Stolte

    No preview · Article · Feb 2005 · Zeitschrift für Gastroenterologie
  • K Ocran · M Ortner · W Voderholzer

    No preview · Article · Jul 2004 · Endoscopy

  • No preview · Article · Apr 2004 · Gastrointestinal Endoscopy
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    ABSTRACT: The detection of early malignant lesions of the GI tract is an important field of research. At present, random biopsies and biopsies of suspect lesions are the procedures of choice, although as much as 20% of dysplasia are missed. New diagnostic and therapeutic tools are currently under evaluation in premalignant lesions of ulcerative colitis or Barrett's esophagus. The use of an endoscopic capsule, a new method of investigation for the small intestine, is indicated in case of acute or chronic bleeding after completion of an inconclusive upper and a lower endoscopy. The new endoscopic procedures for reflux esophagitis are at the moment not a therapeutical alternative for the established PPI treatment. The different endoscopic treatments in combination with PPI therapy for dysplastic lesions or early cancer in Barrett's esophagus can be a curative alternative to surgery in patients with high operative risk. Photodynamic therapy with hematoporphyrin derivates in association with biliary stent is a new promising approach in the palliative treatment of cholangiocarcinomas. It combines relives of cholestasis and reduction of the tumor mass. Survival, as well as Quality of Life can be improved considerably. Therefore, it should be offered to all patients with nonresectable cholangiocarcinoma.
    No preview · Article · Jan 2004
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    ABSTRACT: It is still difficult to visualize changes in the small intestine. Wireless capsule enteroscopy is a new method that promises to provide new insights into the small intestine. In a prospective study, the diagnostic yield of wireless enteroscopy was therefore compared with computed tomography (CT) enteroclysis. Twenty-two patients with suspected small-bowel pathology underwent CT enteroclysis and wireless capsule enteroscopy examinations, conducted by two independent blinded investigators. The results of the two investigations (diagnoses and the number, extent, and location of lesions detected) were compared by a third investigator. The patients included in the study had obscure gastrointestinal bleeding (n = 8), Crohn's disease (n = 8), unexplained diarrhea (n = 5), or suspected carcinoid tumor (n = 1). Pathological lesions were detected using capsule enteroscopy in 13 patients (59 %) and using CT enteroclysis in eight (36 %; P = 0.12). In seven patients (one case each of colonic Crohn's disease, diverticulitis, Meckel's diverticulum, carcinoid tumor, mesothelioma, colonic polyps, and irritable bowel syndrome), no pathological changes were found in the small intestine using either method. The diagnosis was established by wireless capsule enteroscopy in four patients with obscure bleeding, whereas CT enteroclysis was positive in only one patient ( P = 0.1). Crohn's disease was found in two patients with unexplained diarrhea. Small-bowel lesions were identified in six patients with known Crohn's disease using capsule enteroscopy or CT enteroclysis. The only side effect of wireless capsule enteroscopy observed was abdominal pain in one patient with Crohn's disease. There were no serious side effects with CT enteroclysis. Wireless capsule enteroscopy detects more small-bowel lesions than CT enteroclysis in patients with obscure gastrointestinal bleeding and Crohn's disease.
    No preview · Article · Jan 2004 · Endoscopy
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    ABSTRACT: In nonrandomized trials, photodynamic therapy (PDT) had a promising effect on nonresectable cholangiocarcinoma (NCC). This prospective, open-label, randomized, multicenter study with a group sequential design compared PDT in addition to stenting (group A) with stenting alone (group B) in patients with NCC. In patients with histologically confirmed cholangiocarcinoma, endoscopic or percutaneous double stenting was performed. Patients fulfilling inclusion criteria were randomized to group A (stenting and subsequent PDT) and group B (stenting alone). For PDT, Photofrin 2 mg/kg body wt was injected intravenously 2 days before intraluminal photoactivation (wavelength, 630 nm; light dose, 180 J/cm(2)). Further treatments were performed in cases of residual tumor in the bile duct. The primary outcome parameter was survival time. Secondary outcome parameters were cholestasis and quality of life. PDT resulted in prolongation of survival (group A: n = 20, median 493 days; group B: n = 19, median 98 days; P < 0.0001). It also improved biliary drainage and quality of life. PDT, given in addition to best supportive care, improves survival in patients with NCC. The study was terminated prematurely because PDT proved to be so superior to simple stenting treatment that further randomization was deemed unethical.
    No preview · Article · Nov 2003 · Gastroenterology

Publication Stats

3k Citations
427.74 Total Impact Points

Institutions

  • 2011-2012
    • Inselspital, Universitätsspital Bern
      Berna, Bern, Switzerland
  • 2007
    • University of Lausanne
      Lausanne, Vaud, Switzerland
  • 2003-2007
    • University Hospital of Lausanne
      • • Service d'oto-rhino-laryngologie
      • • Service de gastro-entérologie et d'hépatologie
      Lausanne, Vaud, Switzerland
  • 1996-2005
    • Humboldt-Universität zu Berlin
      • • Department of Psychology
      • • Department of Biology
      Berlín, Berlin, Germany
  • 2001
    • University of Leipzig
      Leipzig, Saxony, Germany
    • University of Iowa
      • Department of Pediatrics
      Iowa City, Iowa, United States
    • Physikalisch-Technische Bundesanstalt
      Brunswyck, Lower Saxony, Germany
  • 1998-2000
    • Charité Universitätsmedizin Berlin
      • Medical Outpatient Department
      Berlín, Berlin, Germany
    • University of Vienna
      Wien, Vienna, Austria