Variations of common bile duct diameter after endoscopic sphincterotomy.

Diameters of the common bile duct (CBD) and common hepatic duct (CHD) were measured before and after endoscopic sphincterotomy (EPT) in 100 patients. There was a significant reduction of the lumen diameter in both the CBD and CHD (p less than 0.01) after EPT. A comparison between 32 patients without symptoms (such as pain, residual stones, and elevated levels of liver enzymes) and 19 patients with remaining symptoms after EPT, showed a statistically significant reduction in both CBD and CHD diameters (p less than 0.001) in the former group, and no statistically proven changes in the diameters in the latter group, since a change of less than 1.5 mm was not considered significant. Therefore, the absence of a reduction or a dilatation of the diameter of the CBD after EPT may suggest that these patients may have persisting complaints after EPT. Measurements on models (phantoms) show that body position of the patient during endoscopic retrograde cholangiopancreatography (ERCP) has little and negligible influence on the measured diameters of the CBD and CHD.