Algorithmic approach to utilization of CT scans for detection of internal hernia in the gastric bypass patient

Maria S Altieri; Aurora D Pryor; Dana A Telem; Keneth Hall; Collin Brathwaite; Marlene Zawin

doi:10.1016/j.soard.2015.02.010

Algorithmic approach to utilization of CT scans for detection of internal hernia in the gastric bypass patient

Surg Obes Relat Dis. 2015 Nov-Dec;11(6):1207-11. doi: 10.1016/j.soard.2015.02.010. Epub 2015 Feb 16.

Authors

Maria S Altieri¹, Aurora D Pryor², Dana A Telem², Keneth Hall³, Collin Brathwaite³, Marlene Zawin⁴

Affiliations

¹ Division of Bariatric and Advanced Gastrointestinal Surgery, Department of Surgery, Stony Brook University Medical Center, Stony Brook, New York. Electronic address: maria.altieri@stonybrookmedicine.edu.
² Division of Bariatric and Advanced Gastrointestinal Surgery, Department of Surgery, Stony Brook University Medical Center, Stony Brook, New York.
³ Division of Bariatric Surgery Program, Department of Surgery, Winthrop University Hospital, Mineola, New York.
⁴ Department of Radiology, Stony Brook Medical Center, Stony Brook, New York.

PMID: 25843399
DOI: 10.1016/j.soard.2015.02.010

Abstract

Background: While surgical exploration remains the gold standard for diagnosing internal hernia (IH) after certain bariatric surgeries, decisions for operative intervention are often based on computed tomography (CT) findings.

Objectives: The aim of this study is to review our institutional experience and create an algorithm to approach patients presenting with abdominal pain and/or emesis after certain bariatric procedures.

Settings: University Hospital

Methods: Following institutional review board approval, a retrospective chart review of all patients presenting with obstruction symptoms after laparoscopic Roux-en-Y gastric bypass (LRYGB) was performed at 2 institutions from 2008 to 2013. Patients without CT scans or with incidental hernia defect findings were excluded. CT and intraoperative findings were compared via univariate statistical analysis.

Results: Fifty-two patients who underwent an operation for a suspected IH were identified. Of the 50 patients, 25 (50%) had IH at operation. Twenty-nine patients (58%) had positive CT scans read for IH and/or obstruction. Of these 29, 19 (66%) were found to have IH at operation and 10 (34%) underwent negative diagnostic laparoscopy. Of the 21 patients with negative CT scans, 6 (29%) had IH at operation versus 15 (71%) who were negative. The sensitivity of CT scan to detect an internal hernia is 76% with 95% confidence interval (CI) [53% to 90%] and specificity is 60% with 95% CI [39% to 78%]. Sensitivity increased to 96% with 95% CI [78% to 99.8%] when combining CT scans with neutrophilia findings.

Conclusion: Positive CT scans are sensitive for IH but not specific. CT scans will not detect IH in 1:4 patients; despite negative findings, surgical exploration should remain the gold standard for patients with acute abdominal pain after LRYGB or biliopancreatic diversion when IH is a consideration.

Keywords: Bariatric surgery; CT scan; Roux-en-Y gastric bypass; Sensitivity; Specificity.

Publication types

Multicenter Study

MeSH terms

Adult
Algorithms*
Female
Follow-Up Studies
Gastric Bypass / adverse effects*
Hernia, Abdominal / diagnostic imaging*
Hernia, Abdominal / etiology
Humans
Male
Obesity, Morbid / surgery*
Postoperative Complications*
ROC Curve
Retrospective Studies
Tomography, X-Ray Computed / statistics & numerical data*