CT IMAGING OF BILIARY ENTERIC FISTULA

Background: To define the signs useful for differentiating between gal lbladder-enteric fistula (GB-EF) and common bile duct-enteric fistula (CBD-EF) on computed tomography (CT) because the prognosis and managem ent of the two are different. Methods: CT scans in 13 patients with pn eumobilia, who had not had surgical biliary-enteric anastomosis and en doscopic sphincterotomy, were reviewed, The presence of fistula itself , the location of air in the biliary system, and the appearance of the gallbladder were assessed. Results: The causes of pneumobilia were GB -EF in seven patients, CBD-EF in three patients, emphysematous cholecy stitis (EC) in one patient, gallbladder cancer (GBC) in one patient, a nd incompetent sphincter of Oddi in one patient. In three of seven GB- EF patients (43%) and in none of the three CBD-EF patients (0%), the f istula itself was detected, Air was detected in the common bile duct i n four of seven GB-EF (57%) and in all three CBD-EF (100%) patients, a nd GBC, In six of seven GB-EF (86%) and in one of three CBD-EF (33%) p atients, the gallbladder was contracted. Thus, the location of air and the contraction of gallbladder were useful signs to differentiate GB- EF from CBD-EF. Conclusion: CT can distinguish between GB-EF and CBD-E F.