Optimal tomographic technique to demonstrate common bile duct stones. An in vitro study.
Six degree and 10 degree circular modes represent the optimal methods available for intravenous cholangiography with tomography within the technical limitations and constraints outlined in this study. The 10 degree mode is superior in the presence of superimposed gas. Ten degree linear tomography is an efficient method for determining the level of the common bile duct but is not the optimal method for obtaining image detail. Thin secretion unidirectional or pleuridirectional modes are occasionally helpful in delineating fine details. The zone of focus is very narrow, permitting very limited sampling within the usual zone of interest. These modes are inefficient in determining the level of the duct and produce less useful image detail than 10 degree circular tomography for ducts of normal, or slightly larger than normal diameters. They are seldom indicated as the primary modality in tomography of the common bile duct.
D042882:Gallstones / Q000000981:diagnostic imaging*; D008954:Models, Biological; D013679:Technology, Radiologic; D014056:Tomography, X-Ray / Q000379:methods*