Ballooning of the papilla during contrast injection: the semaphore of a choledochocele.

BACKGROUND: Choledochocele is a rare abnormality involving the intramural segment of the common bile duct. ERCP is essential to demonstrate a choledochocele. The aim of this study was to investigate the duodenoscopic and cholangiographic findings during ERCP.

METHODS: Over a 4-year period, 17 symptomatic patients (8 men, 9 women; age range 45 to 83 years) were identified as having choledochoceles. The diagnosis of choledochocele was made by both duodenoscopic and cholangiographic findings.

RESULTS: As a characteristic duodenoscopic finding, the enlarged bulging papilla was noted in 8 patients (47%), whereas a normal-appearing papilla was noted in 9 patients (53%) before the injection of contrast media. However, in all 17 patients progressive enlargement or ballooning of the papilla was noted during contrast injection. The maximum diameter of the choledochocele, determined by cholangiography, was significantly larger (19 +/-4 mm) in patients with initially bulging papilla than in those with normal-appearing papilla (9+/-3 mm) (p < 0.05).

CONCLUSIONS: Ballooning of the papilla during contrast injection may be a specific duodenoscopic finding for choledochocele. To avoid missing the diagnosis of a choledochocele, especially when it is small, it is important to watch the papilla carefully during contrast injection.