Jelle Haringsma

Erasmus MC, Rotterdam, South Holland, Netherlands

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Publications (131)706.17 Total impact

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    ABSTRACT: This Guideline is an official statement of the European Society of Gastrointestinal Endoscopy (ESGE). The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system 1 2 was adopted to define the strength of recommendations and the quality of evidence. Main recommendations 1 ESGE recommends endoscopic en bloc resection for superficial esophageal squamous cell cancers (SCCs), excluding those with obvious submucosal involvement (strong recommendation, moderate quality evidence). Endoscopic mucosal resection (EMR) may be considered in such lesions when they are smaller than 10 mm if en bloc resection can be assured. However, ESGE recommends endoscopic submucosal dissection (ESD) as the first option, mainly to provide an en bloc resection with accurate pathology staging and to avoid missing important histological features (strong recommendation, moderate quality evidence). 2 ESGE recommends endoscopic resection with a curative intent for visible lesions in Barrett's esophagus (strong recommendation, moderate quality evidence). ESD has not been shown to be superior to EMR for excision of mucosal cancer, and for that reason EMR should be preferred. ESD may be considered in selected cases, such as lesions larger than 15 mm, poorly lifting tumors, and lesions at risk for submucosal invasion (strong recommendation, moderate quality evidence). 3 ESGE recommends endoscopic resection for the treatment of gastric superficial neoplastic lesions that possess a very low risk of lymph node metastasis (strong recommendation, high quality evidence). EMR is an acceptable option for lesions smaller than 10 - 15 mm with a very low probability of advanced histology (Paris 0-IIa). However, ESGE recommends ESD as treatment of choice for most gastric superficial neoplastic lesions (strong recommendation, moderate quality evidence). 4 ESGE states that the majority of colonic and rectal superficial lesions can be effectively removed in a curative way by standard polypectomy and/or by EMR (strong recommendation, moderate quality evidence). ESD can be considered for removal of colonic and rectal lesions with high suspicion of limited submucosal invasion that is based on two main criteria of depressed morphology and irregular or nongranular surface pattern, particularly if the lesions are larger than 20 mm; or ESD can be considered for colorectal lesions that otherwise cannot be optimally and radically removed by snare-based techniques (strong recommendation, moderate quality evidence). © Georg Thieme Verlag KG Stuttgart · New York.
    Endoscopy 09/2015; 47(9):829-854. DOI:10.1055/s-0034-1392882 · 5.05 Impact Factor
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    ABSTRACT: The American Society for Gastrointestinal Endoscopy Committee on Outcomes Research has recommended monitoring nine endoscopic retrograde cholangiopancreatography (ERCP)-specific quality indicators for quality assurance in ERCP. With the development of a self-assessment tool for ERCP (Rotterdam Assessment Form for ERCP-RAF-E), key indicators can easily be assessed. The aim of this study was to test in daily practice an easy-to-use form for assessment of procedural quality in ERCP and to determine ERCP quality outcomes in a tertiary referral hospital. This was a prospective study carried out in a tertiary referral hospital. In January 2008, a quality self-assessment programme was started. Five qualified endoscopists participated in this study. All ERCPs were appraised using RAF-E. Primary parameters were common bile duct (CBD) cannulation rate and procedural success. The indication was classified and procedural difficulty was graded; success rates of therapeutic interventions were measured for all different difficulty degrees. A total number of 1691 ERCPs were performed. 1515 (89.6%) of these were appraised using RAF-E. Median CBD cannulation success rate was 94.1%. Successful sphincterotomy was accomplished in almost all patients (median 100%; range 98.2-100%). Stent placement was successful in 97.8% and complete stone extraction, if indicated, was achieved in 86.8%. Quality indicators for ERCP can be measured using the Rotterdam self-assessment programme for ERCP. Outcome data in ERCPs obtained with this RAF-E provide insight into the quality of individual as well as group performance and can be used to assess and set standards for quality control in ERCP.
    01/2014; 5(1):10-16. DOI:10.1136/flgastro-2013-100334
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    ABSTRACT: Education and competency assessment in gastrointestinal endoscopy is important. Concerning colonoscopy, it is not completely clear what the best way is to learn this procedure, what defines competency in colonoscopy, and which factors define a high-quality colonoscopy. The aim of this study was to determine the endoscopist-related factors that define a high-quality colonoscopy. A three-round Delphi survey among expert endoscopists was carried out. In round 1, the panel was invited to identify factors essential for a good colonoscopy. The listed factors were to be ranked during the second round. In the third round, a 5-point Likert scale was added. A reference panel was invited to assess the items as well. 14 expert endoscopists from the Netherlands were invited, of whom eight participated (57 %). A list of 30 items important for colonoscopy was formulated. After the following rounds, consensus was reached on 16 items. Validation was conducted among eight trainees and eight experienced endoscopists (response 100 %). The groups agreed on the importance of all but one factor (p = 0.001). This Delphi survey has made explicit the endoscopist-related factors that are important for optimal colonoscopy. This might provide trainers more support regarding concrete competency assessment of trainees in endoscopy.
    12/2013; 3(1). DOI:10.1007/s40037-013-0099-3
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    ABSTRACT: Self-expanding metal stents (SEMSs) provide effective palliation in patients with malignant dysphagia. However, although life expectancy is generally limited, reintervention rates because of stent dysfunction are significant. New SEMSs are being designed to overcome this drawback. To investigate whether the results of SEMS placement could be improved with a new SEMS design. Consecutive patients with dysphagia or leakage caused by malignant esophageal disease. In a multicenter randomized clinical trial, consecutive patients with dysphagia or leakage because of malignant esophageal disease were randomized to placement of a conventional stent or the new stent. Patients were followed up by scheduled telephone calls 1 and 3 months after SEMS insertion. A total of 80 patients (73% male; median age, 67 years [range, 40-92 years]) were included. One patient refused follow-up. Technical success was 100% in both groups. The reintervention rate was 15/40 (38%) for the conventional stent and 4/39 (10%) for the new stent (P = .004). Major complications, including aspiration pneumonia and bleeding, occurred more frequently with the conventional stent (10/40, 25%) than with the new stent (3/39, 8%, P = .04). There was no difference in overall survival between the 2 groups. Inclusion of patients with a perforation or fistula. The conventional stent and the new stent were equally effective in the relief of malignant dysphagia and sealing fistulae. The conventional stent was associated with more stent dysfunction and a significantly higher rate of major complications. Patients treated with the new stent also needed significantly fewer reinterventions than did those treated with a conventional stent. This sets the preference for the new stent over the conventional stent for patients with malignant esophageal disease.
    Gastrointestinal endoscopy 07/2012; 76(1):52-8. DOI:10.1016/j.gie.2012.02.050 · 5.37 Impact Factor
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    ABSTRACT: We evaluated a new assessment technique for colonoscopy training. We prospectively evaluated colonoscopy skills during training using the Rotterdam Assessment Form for colonoscopy. The questionnaire covers cecal intubation, procedural time, and subjective grading of performance. Individual learning curves are compared with a group reference. Nineteen trainees self-assessed 2,887 colonoscopies. The cecal intubation rate improved from 65% at baseline to 78% and 85% after 100 and 200 colonoscopies, respectively. In our training program the 90% threshold was reached after 280 colonoscopies on average. Cecal intubation time improved from 13:10 minutes at baseline to 9:30 and 8:30 after 100 and 200 colonoscopies, respectively. This novel self-assessment form allows individual learning curves to be compared with a group reference, provides data on the development of dexterity skills and individual training targets, and stimulates trainees to identify steps for self-improvement.
    The American Journal of Gastroenterology 07/2012; 107(7):971-5. DOI:10.1038/ajg.2011.481 · 10.76 Impact Factor
  • Gastrointestinal Endoscopy 04/2012; 75(4):AB277-AB278. DOI:10.1016/j.gie.2012.03.706 · 5.37 Impact Factor
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    ABSTRACT: Fully-covered self expandable metal stents (fcSEMSs) are an alternative to progressive plastic stenting for the treatment of benign biliary strictures (BBS) with the prospect of a higher treatment efficacy and the need for fewer ERCPs, thereby reducing the burden for patients and possibly costs. Key to this novel treatment is safe stent removal. To investigate the feasibility and safety of stent removal of a fcSEMS with a proximal retrieval lasso: a long wire thread integrated in the proximal ends of the wire mesh that hangs freely in the stent lumen. Pulling it enables gradual removal of the stent inside-out. A secondary aim was success of stricture resolution. Non-randomized, prospective follow-up study with 3 sequential cohorts of 8 patients with BBS. Academic tertiary referral center. Eligible patients had strictures either postsurgical (post-cholecystectomy (LCx) or liver transplantation (OLT)), due to chronic pancreatitis (CP), or papillary stenosis (PF). Strictures had to be located at least 2 cm below the liver hilum. All patients had one plastic stent in situ across the stricture and had not undergone previous treatment with either multiple plastic stents or fcSEMS. The first cohort of patients underwent stent placement for 2 months, followed by 3 months if the stricture had not resolved. The second and third cohort started with 3 months and 4 months, respectively, both followed by another 4 months if indicated. Treatment success was defined by stricture resolution at cholangiography, the ability to pass an inflated extraction balloon and clinical follow-up (at least 6 months). safety of stent removal. Secondary outcomes were complications and successful stricture resolution. A total of 23 patients (11 female; 20-67 yrs) were eligible for final analysis. One patient developed a malignant neuroendocrine tumor in the setting of CP. Strictures were caused by CP (13), OLT (6), LCx (3) and PF (1). In total 39 fcSEMS were placed and removed. Removals were easy and without complications. Transient pain after insertion was common (13 of 23/56%) but was easily managed by analgesics in all patients. Other complications were cholecystitis (1), cholangitis due to stent migration (1, stent replaced) or stent clogging (2, managed endoscopically) and worsening of CP (2). In these patients, the fcSEMS was removed and replaced after pancreatic sphincterotomy and PD stent placement. Median follow-up was 15 months (range 11-25). Overall treatment success was 61% (14/23); in the CP group 46%, in the remaining patients 80% (p = 0.11). Patients with stricture resolution after removal of the first stent (n = 7; success 6/7) showed a trent towards a more sustained treatment success than patients who needed a 2nd stent placement (n = 16; success 8/16); p = 0.12). Small number of patients with regard to secondary outcomes. Removal of a new type of fcSEMS with a proximal retrieval lasso in patients with BBS proved easy and uncomplicated. Treatment success for CP strictures was higher compared to what is known from results of progressive plastic stenting protocols. For other indications treatment success was comparable to progressive plastic stenting, but with the prospect of fewer ERCP procedures.
    Gastrointestinal endoscopy 02/2012; 75(4):783-9. DOI:10.1016/j.gie.2011.10.022 · 5.37 Impact Factor
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    ABSTRACT: Endoscopic submucosal dissection (ESD) demands a new level of endoscopic skill in Europe. A 2-day workshop was set up for trainees to carry out five ESD each in order to obtain the skill level required to perform ESD in the stomach or rectum. This study describes: (i) the workshop setup; (ii) the participant's performance; and (iii) the training effect on post-workshop clinical ESD performance. Eighteen very experienced European endoscopists participated in four half-day (4.5 h) training sessions, with everybody rotating daily through six separate training stations (two each with dual, hook, or hybrid knives) with expert tutors. One anesthetized piglet was used per station and session. After 1 year, the clinical ESD performance was surveyed to estimate the training effect of the workshop. Overall, 74 ESD were performed, that is, 4.1 ESD per participant. On average ESD lasted 57 min for 6 cm(2) specimens. We detected a 22% rate of perforation (16 of 74 ESD with perforations), mostly attributable to participants with less experience in ESD. Those who started clinical ESD within 1 year after the workshop performed 144 clinical ESD (median 8 [0-20] per trainee) mostly in the stomach (40%) and large bowel (46%) with an acceptable rate of perforation (9.7%) and surgical repair (3.5%) without mortality or persistent morbidity. Intense skill training for ESD is needed to reduce the risk of perforation, as demonstrated by the results of this workshop. We show that experimental ESD training, however, enables skilled European endoscopists to perform ESD in standard locations with moderate risk of perforation during the clinical learning curve.
    Digestive Endoscopy 10/2011; 23(4):281-9. DOI:10.1111/j.1443-1661.2011.01129.x · 2.06 Impact Factor
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    ABSTRACT: Self-expandable metals stents (SEMSs) have increasingly been used as a temporary device to bridge chemoradiotherapy in patients with malignant esophageal disease or in patients with benign esophageal defects or stenosis. To evaluate the outcome of removal of SEMSs in a large cohort of patients with benign and malignant esophageal disease. Observational study with standardized treatment and follow-up. Single university center. Between 2001 and 2010, 95 consecutive patients referred for endoscopic SEMS extraction were included. Endoscopic stent removal. Technical and functional outcome and complications. A total of 124 stent extractions were undertaken in 95 patients; both partially covered (68%) and fully covered (32%) SEMSs were removed. Three patients had 2 overlapping SEMSs in place. Successful primary removal was achieved in 89%; the secondary removal rate was 96%. Uncomplicated primary removal rate was significantly higher for fully covered versus partially covered stents (P = .035) and for single versus overlapping stents (P = .033). Patients with a complicated stent removal had the stent in place significantly longer compared with patients with an uncomplicated primary stent removal (126 days vs 28 days; P = .01). Surgical removal was required in 3 patients (2.4%). Six moderate and severe complications (5%) related to the endoscopic extraction occurred. Retrospective, nonrandomized study design. Primary endoscopic removal of an SEMS is feasible in the majority of patients with benign and malignant esophageal disease. A longer time that a stent is in place and the use of partially covered SEMSs both impede removal. Moreover, overlapping SEMSs should be avoided for temporary use because stent disintegration and subsequent complications may occur.
    Gastrointestinal endoscopy 05/2011; 74(1):44-50. DOI:10.1016/j.gie.2011.02.020 · 5.37 Impact Factor
  • Gastrointestinal Endoscopy 04/2011; 73(4). DOI:10.1016/j.gie.2011.03.747 · 5.37 Impact Factor
  • Gastrointestinal Endoscopy 04/2011; 73(4). DOI:10.1016/j.gie.2011.03.140 · 5.37 Impact Factor
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    ABSTRACT: Several studies have evaluated predictors for complications of endoscopic retrograde cholangiopancreatography (ERCP), but their relative importance is unknown. In addition, currently used blood tests to detect post-ERCP pancreatitis are inconsistent. The aim of this study was to determine predictors of post-ERCP complications that could discriminate between patients at highest and lowest risk of post-ERCP complications and to develop a model that is able to identify patients that can safely be discharged shortly after ERCP. In a single-center, retrospective analysis over the period 2002-2007, predictors of post-ERCP complications were evaluated in a multivariable analysis and compared with those identified from a literature review. A prognostic model was developed based on these risk factors, which was further evaluated in a prospective patient population. From our retrospective analysis and literature review, we selected the eight most important risk factors for post-ERCP pancreatitis and cholangitis. In the prognostic model, the risk factors (precut) sphincterotomy, sphincter of Oddi dysfunction, younger age, female gender, history of pancreatitis, pancreas divisum, and difficult cannulation accounted for a score of 1 each, whereas primary sclerosing cholangitis (PSC) accounted for a score of 2. A sum score of 4 or more in the prognostic model was associated with a high risk of developing pancreatitis and cholangitis (27%; 6/22) in the prospective patient population, whereas a sum score of 3 or less was associated with a low to intermediate risk (8%; 20/252). We identified specific patient- and procedure-related factors that are associated with post-ERCP complications. The prognostic model based on these factors is able to identify patients who can be safely discharged the same day after ERCP.
    Surgical Endoscopy 04/2011; 25(9):2892-900. DOI:10.1007/s00464-011-1638-9 · 3.26 Impact Factor
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    ABSTRACT: Virtual reality (VR) endoscopy simulators are increasingly being used in the training of novice endoscopists. There are, however, insufficient data regarding the effect of simulator training on the early learning curve of novice endoscopists. The aim of this study was to assess the clinical performance of novice endoscopists during colonoscopy after intensive and prolonged training on a VR endoscopy simulator. Prospective study. Single university medical center. Patient-based assessment (PBA) of performance was carried out on patients routinely scheduled for colonoscopy. Eighteen trainees without any endoscopic experience were included in the study. They were divided into 2 groups. The simulator-training program consisted of either 50 (group I) or 100 (group II) VR colonoscopies. After 10, 30, and 50 (group I) and after 20, 60, and 100 (group II) VR colonoscopies, trainees underwent both simulator-based assessment and PBA. Cecal intubation time, colonic insertion depth, and cecal intubation rate. Eighteen novices participated in the study. All completed VR training and assessments. The mean cecal intubation time on the SBA decreased from a baseline of 9.50 minutes to 2.20 minutes at completion of the training (P = .002). Colonic insertion depth during PBA improved from 29.4 cm to 63.7 cm (P < .001). The learning effect of simulator training ceased after 60 colonoscopies. Single-center study, no formal sample size calculation. VR training by using a colonoscopy simulator leads to a significant improvement in performance with the simulator itself and, more importantly, to significantly improved performances during patient-based colonoscopy. This study demonstrates the rationale for intensive simulator training in the early learning curve of novices performing colonoscopy. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.
    Gastrointestinal Endoscopy 04/2011; 73(4). DOI:10.1016/j.gie.2011.03.945 · 5.37 Impact Factor
  • Article: Response.
    N C M van Heel · J Haringsma
    Gastrointestinal endoscopy 04/2011; 73(4):850. DOI:10.1016/j.gie.2010.10.004 · 5.37 Impact Factor
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    ABSTRACT: Delayed hemorrhage is an infrequent, but serious complication of colonoscopic polypectomy. Large size is the only polyp-related factor that has been unequivocally proven to increase the risk of delayed bleeding. It has been suggested that location in the right hemi-colon is also a risk factor. The objective of this study was to determine whether polyp location is an independent risk factor for delayed post-polypectomy hemorrhage. A retrospective case-control study was conducted in two university hospitals and two community hospitals. Thirty-nine cases and 117 controls were identified. In multivariate analysis, size and location were found to be independent polyp-related risk factors for delayed type hemorrhage. The risk increased by 13% for every 1 mm increase in polyp diameter (odds ratio (OR) 1.13, 95% confidence interval (CI) 1.05-1.20, P<0.001). Polyps located in the right hemi-colon had an OR of 4.67 (1.88-11.61, P=0.001) for delayed hemorrhage. Polyps in the cecum seemed to be especially at high risk in univariate analysis (OR 13.82, 95% CI 2.66-71.73), but this could not be assessed in multivariate analysis as the number of cases was too small. Polyp type (sessile or pedunculated) was not a risk factor. Polyp location in the right hemi-colon seems to be an independent and substantial risk factor for delayed post-polypectomy hemorrhage. A low threshold for preventive hemostatic measures is advised when removing polyps from this region.
    The American Journal of Gastroenterology 01/2011; 106(6):1119-24. DOI:10.1038/ajg.2010.507 · 10.76 Impact Factor
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    ABSTRACT: Three different classification systems for the evaluation of Barrett's esophagus (BE) using magnification endoscopy (ME) and narrow-band imaging (NBI) have been proposed. Until now, no comparative and external evaluation of these systems in a clinical-like situation has been performed. To compare and validate these 3 classification systems. Prospective validation study. Tertiary-care referral center. Nine endoscopists with different levels of expertise from Europe and Japan participated as assessors. Thirty-two patients with long-segment BE. From a group of 209 standardized prospective recordings collected on BE by using ME combined with NBI, 84 high-quality videos were randomly selected for evaluation. Histologically, 28 were classified as gastric type mucosa, 29 as specialized intestinal metaplasia (SIM), and 27 as SIM with dysplasia/cancer. Assessors were blinded to underlying histology and scored each video according to the respective classification system. Before evaluation, an educational set concerning each classification system was carefully studied. At each assessment, the same 84 videos were displayed, but in different and random order. Accuracy for detection of nondysplastic and dysplastic SIM. Interobserver agreement related to each classification. The median time for video evaluation was 25 seconds (interquartile range 20-39 seconds) and was longer with the Amsterdam classification (P < .001). In 65% to 69% of the videos, assessors described certainty about the histology prediction. The global accuracy was 46% and 47% using the Nottingham and Kansas classifications, respectively, and 51% with the Amsterdam classification. The accuracy for nondysplastic SIM identification ranged between 57% (Kansas and Nottingham) and 63% (Amsterdam). Accuracy for dysplastic tissue was 75%, irrespective of the classification system and assessor expertise level. Interobserver agreement ranged from fair (Nottingham, κ = 0.34) to moderate (Amsterdam and Kansas, κ = 0.47 and 0.44, respectively). No per-patient analysis. All of the available classification systems could be used in a clinical-like environment, but with inadequate interobserver agreement. All classification systems based on combined ME and NBI, revealed substantial limitations in predicting nondysplastic and dysplastic BE when assessed externally. This technique cannot, as yet, replace random biopsies for histopathological analysis.
    Gastrointestinal endoscopy 01/2011; 73(1):7-14. DOI:10.1016/j.gie.2010.09.023 · 5.37 Impact Factor
  • Nicoline van Heel · Jelle Haringsma · Ernst J. Kuipers
    Gastroenterology 01/2011; 140(5). DOI:10.1016/S0016-5085(11)62360-3 · 16.72 Impact Factor
  • Gastroenterology 01/2011; 140(5). DOI:10.1016/S0016-5085(11)62788-1 · 16.72 Impact Factor
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    ABSTRACT: Background Surveillance of premalignant gastric lesions relies mainly on random biopsy sampling. Narrow band imaging (NBI) may enhance the accuracy of endoscopic surveillance of intestinal metaplasia (IM) and dysplasia. We aimed to compare the yield of NBI to white light endoscopy (WLE) in the surveillance of patients with IM and dysplasia. Methods Patients with previously identified gastric IM or dysplasia underwent a surveillance endoscopy. Both WLE and NBI were performed in all patients during a single procedure. The sensitivity of WLE and NBI for the detection of premalignant lesions was calculated by correlating endoscopic findings to histological diagnosis. Results Forty-three patients (28 males and 15 females, mean age 59 years) were included. IM was diagnosed in 27 patients; 20 were detected by NBI and WLE, four solely by NBI and three by random biopsies only. Dysplasia was detected in seven patients by WLE and NBI and in two patients by random biopsies only. Sixty-eight endoscopically detected lesions contained IM: 47 were detected by WLE and NBI, 21 by NBI only. Nine endoscopically detected lesions demonstrated dysplasia: eight were detected by WLE and NBI, one was detected by NBI only. The sensitivity, specificity, positive and negative predictive values for detection of premalignant lesions were 71, 58, 65 and 65% for NBI and 51, 67, 62 and 55% for WLE, respectively. Conclusions NBI increases the diagnostic yield for detection of advanced premalignant gastric lesions compared to routine WLE.
    Digestive Diseases and Sciences 12/2010; 55(12):3442-8. DOI:10.1007/s10620-010-1189-2 · 2.61 Impact Factor
  • Bart J Veldt · Jelle Haringsma · Klaas W Florijn · Ernst J Kuipers
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    ABSTRACT: Intramural hematoma of the small intestine is a complication of anticoagulant treatment with an estimated incidence of 1 case per 2500 anticoagulated patients per year. Patients may present with signs of small bowel obstruction or, in case of a ruptured hematoma, with upper gastrointestinal tract hemorrhage and hypovolemic shock. Case report and review of the literature. We present a case of a 73-year-old male who was referred for a protruding mass in the duodenum and subsequently developed hematemesis and melena caused by a ruptured hematoma of the duodenal wall. Although intramural hematoma of the duodenum is a rare complication of anticoagulant therapy, early diagnosis with subsequent correction of coagulation parameters is of vital importance.
    Scandinavian Journal of Gastroenterology 11/2010; 46(3):376-9. DOI:10.3109/00365521.2010.531484 · 2.36 Impact Factor

Publication Stats

3k Citations
706.17 Total Impact Points


  • 2002–2015
    • Erasmus MC
      • Department of Gastroenterology and Hepatology
      Rotterdam, South Holland, Netherlands
  • 2004–2012
    • Erasmus Universiteit Rotterdam
      • Department of Gastroenterology and Hepatology
      Rotterdam, South Holland, Netherlands
  • 2010
    • Cliniques Universitaires Saint-Luc
      Bruxelles, Brussels Capital Region, Belgium
  • 2009
    • Imperial College London
      Londinium, England, United Kingdom
  • 2001
    • Ontario Institute for Cancer Research
      Toronto, Ontario, Canada
  • 1998–1999
    • University of Amsterdam
      • Department of Gastroenterology and Hepatology
      Amsterdamo, North Holland, Netherlands
  • 1988–1998
    • Academisch Medisch Centrum Universiteit van Amsterdam
      • • Academic Medical Center
      • • Department of Gastroenterology and Hepatology
      Amsterdamo, North Holland, Netherlands
  • 1997
    • Kennemer Gasthuis
      • Department of Surgery
      Haarlem, North Holland, Netherlands