THE ANATOMICAL location of the distal common bile duct is such that even the experienced surgeon contemplates investigation of this area with extreme caution. Even with the duodenum well kocherized, one gains little information by careful inspection of the posterior aspect of the head of the pancreas, in which the distal common duct is embedded in varying degrees. Careful palpation of this area likewise usually yields little in the way of accurate information, unless one is dealing with a relatively large lesion of the ampulla which protrudes into the duodenal lumen or with a well advanced, distinct carcinoma of the head of the pancreas. Duodenotomy also does not help a great deal unless one encounters a lesion of the ampullary area which has produced gross changes. The various sounding and probing instruments designed for exploration of the common bile duct leave considerable to be desired.
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