Clinical value of multi-slice computed tomography in the diagnosis of biliary gallbladder-duodenal fistula

Objective To summarize the characteristics and clinical value of multi-slice spiral computed tomography (MSCT) examination in the biliary gallbladder-duodenal fistula. Methods The imaging data of 28 patients with gallbladder-duodenal fistula who were admitted to the Wuxi No. 2 Hospital of Nanjing Medical University between June 2012 and March 2015 were retrospectively analyzed. All the 28 patients received MSCT examinations, and the imaging changes were observed and analyzed, including the location of lesions, figures of fistulous tract, shrinking or enlarging gallbladder, pneumotosis and stones of gallbladder or bile duct. Results Of the 28 patients, fistula located at the duodenal bulb were detected in 14 patients, junction of the bulb and the descending part of the duodenum in 2 patients, ascending duodenum in 7 patients, horizontal part in 5 patients. Indirect signs of biliary gallbladder-duodenal fistula included that gallbladder volume in 28 patients was significantly reduced, cross sectional area of gallbladder was 2 cm×1 cm-6 cm×2 cm, and gallbladder wall was thickened with an average thickness of 5 mm (range, 4-9 mm). Adhesion of gallbladder and duodenum, unclear boundary, structure disorder and visible effusion surrounding gallbladder were detected. Among 21 patients with biliary gas, 19 patients had pneumotosis of gallbladder and 17 had biliary pneumatosis. Biliary stones were detected in 23 patients including cholecystolithiasis in 19 patients, gallbladder neck stones in 6 patients, common bile duct stones in 13 patients and intra- and extra-hepatic cholangiolithiasis in 1 patient. The diverticulum signs appeared in the duodenum of 11 patients. The direct signs of MSCT in the biliary gallbladder-duodenal fistula included that fistulous tract of 13 patients clearly showed and some were dumbbell-shaped. Two and 2 patients were complicated with gallstone ileus and multiple liver abscesses, respectively. The diagnostic results of MSCT in 28 patients were compared with the results of operative exploration, with an diagnostic concordance rate of 78.6% (22/28), and the diagnostic concordance rate of gallbladder stones was 82.1%(23/28). Conclusions The indirect signs of MSCT in patients with biliary gallbladder-duodenal fistula include pneumotosis of gallbladder or/and biliary gas, gallbladder neck stones or common bile duct stones, gallbladder shrank, adhesion of gallbladder and duodenum, unclear boundary, diverticulum signs in the adhesions of duodenum and gallbladder, and clear orificium fistulae of gallbladder-duodenum is a direct sign of MSCT. Key words: Biliary gallbladder-duodenal fistula; Multi-slice spiral computed tomography; Diagnosis