RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.INTRODUCTION: Transomental herniation is a rare but recognised clinical condition, which usually presents as an emergency with bowel obstruction. It accounts for 1-4% of intra-abdominal herniations. We reviewed 3 patients found to have a transomental defect during elective diagnostic laparoscopy performed for chronic abdominal pain. To our knowledge, there is no case series reported in the literature on transomental defect in the non-emergency situation. CASE PRESENTATION: A retrospective case note analysis of 3 patients, found to have transomental defect during elective diagnostic laparoscopy, was undertaken. Data were gathered with respect to clinical presentation, investigations performed, transomental defect size and outcome of surgery. All patients were followed up for 6 months post-operatively. Three females (age range 18-35 years) were referred with a 3-10 year history of chronic intermittent abdominal pain, often postprandial. Blood tests, radiological investigations (ultrasound, magnetic resonance imaging/computed tomography, small bowel studies) and endoscopy were all normal. In each case, diagnostic laparoscopy revealed the presence of a peripheral defect in the greater omentum, but no actual small bowel herniation. No other pathology was found. These defects were resected, which subsequently led to complete resolution of the patients' symptoms. CONCLUSION: Chronic abdominal pain of unknown aetiology with normal radiological findings may be caused by intermittent obstruction due to small bowel herniation through a transomental defect. This should be considered during elective diagnostic laparoscopy, in the absence of any other obvious pathology. The omentum should be thoroughly inspected as a discrete entity and any such defects should be closed or resected
