L. N. Ubadigbo1, D. M. Coleman1, R. Markert1, S. Choudry1, M. Walusimbi1 1Wright State University,Department Of Surgery,Dayton, OH, USA
Introduction: Incarcerated hernias are a surgical emergency, the diagnosis has historically been physical examination. CT scans provide an alternate way of diagnosing abdominal wall hernias. Radiologists have gone further diagnosing incarceration and strangulation, often making recommendations for urgent surgical intervention without a collaborating physical examination. The objective of this study is to determine the accuracy of multidetector computed tomography (MDCT) in diagnosing a hernia incarceration and ischemia.
Methods: Retrospective study utilizing hospital medical records to identify patients who had both surgery for an abdominal wall hernia or small intestinal obstruction and pre-operative CT scan of the abdomen over a one-year period. The study was reviewed and approved by our Institutional Review Board.
Results: We identified 139 patients with complete medical records who had surgery for abdominal wall hernia repair, 67 (48.2%) of whom had a pre-op CT scan. When results of the CT scans were examined, only 15 out of 67 patients (22.39%) were confirmed with hernia incarceration, of which 9 (60%) were in agreement with the physical examination. Nearly half, 4 of the nine CT scans were without any oral or intravenous contrast. As shown in Table 1, CT accurately excluded hernia incarceration in 86.96% (40 of 46). There were however, 12 false negatives (17.9%) in CT scan group. Consequently, the sensitivity of CT for diagnosing an incarcerated hernia (with pre-operative physical exam as the reference standard) was 43% (95% CI=0.22, 0.66) and specificity 87% (95% CI= 0.74, 0.95).
Conclusion: CT scan is not a reliable alternative to the physical examination in diagnosing or ruling-out hernia incarceration and strangulation but can serve as useful adjunct to a thorough physical examination. We found no evidence that addition of intravenous contrast increases the accuracy of CT scans. This could help reduce the patient cost and better utilize hospital resources.
