Comparison of Imaging Modalities for Detecting Complications in Bariatric Surgery

Purpose: The purpose of this study is to evaluate the results of routine fluoroscopic swallowing study (FSS) imaging 24 h after surgery and computed tomography (CT) on demand based on clinical data, in diagnosing complications after bariatric surgery. Material and Methods: This retrospective study includes 9386 patients that underwent bariatric surgery. A total of 3241 (34.53%) patients underwent FSS imaging following the surgical procedure, and 106 (1.13%) patients underwent CT. Results: Sleeve gastrectomy was performed in 8093 patients (75.81%), gastric bypass was performed in 1281 patients (12%), duodenal switch or biliopancreatic diversion was performed in 12 patients (0.11%), and gastric banding was performed in 1289 patients (12.07%), which were excluded from the study as no imaging modality was used in any of these patients. The sensitivity for FSS was 71.43% and the specificity was 99.85%. An analysis of disease prevalence revealed a value of 0.43% with a positive predictive value of 66.67%. The sensitivity for CT was 71.42% and the specificity was 98%. A disease prevalence analysis revealed a value of 6.60% with a positive predictive value of 83.33%. A comparison of the two modalities showed that FSS has higher specificity values (p < 0.02) and a higher accuracy (p < 0.0001) than CT. Conclusion: CT and FSS have a similar sensitivity for diagnosing complications after bariatric surgery. However, the specificity and accuracy of FSS are superior to that of CT. This study was approved by the instructional ethics committee (Helsinki board) and was registered on the National Institutes of Health (ClinicalTrials.gov) web site with identifier NCT02813122.