Abdominal imaging post bariatric surgery: predictors, usage and utility

Purpose: A lack of well-defined postoperative imaging guidelines for bariatric patients may lead to false-positive findings, radiation exposure, additional cost, and patient anxiety. We investigated our institutional usage and utility of nonroutine postoperative abdominal imaging.

Methods and materials: Laparoscopic gastric bypass and sleeve gastrectomy patients over a 5-year period were retrospectively identified. All bariatric-related nonroutine initial and all subsequent prompted abdominal and pelvic imaging was included.

Results: A total of 578 patients were included (399 gastric bypass, 179 sleeve gastrectomy); 907 nonroutine studies in 69% of patients were performed, and 36% patients underwent computed tomography (CT). Only 20.3% of findings were symptom-related, 26% had benign incidental findings, and 50% were negative. Incidental findings prompted 71 additional studies. Bypass procedure (sleeve versus bypass, odds ratio [OR] .3), older age (median 43 versus 48 years), and lower initial body mass index (BMI) (median 43 versus 45) increased the likelihood of imaging. History of prior abdominal surgery and dyspepsia increased the probability of undergoing CT by an odds ratio of 1.8 and 2.0, respectively (P<.05). History of ulcer (OR .6) or reflux on routine upper gastrointestinal imaging (OR .3) decreased probability (P<.05). Patients who underwent CT were more likely to undergo other abdominal imaging (3 versus 1 study per patient, P<.01).

Conclusions: Postoperative abdominal imaging in the bariatric population is common, with almost 70% of patients undergoing imaging and 70% of findings not related to patient symptoms. Bypass procedure, older age, and lower initial BMI were associated with a higher likelihood of patients undergoing imaging. Heightened understanding of this important subject is necessary to help streamline cost-effective imaging protocols for these patients.