Endoscopic electromyography of the sphincter of Oddi.

Endoscopic electromyography of the human sphincter of ODDI has provided useful information for the patho-physiological studies on the choledocho-duodenal junction. The pattern and rhythm of the electromyogram observed on the spincter of ODDI were different from those of the duodenum recorded simultaneously in basal tracings of our initial four cases. In the half of other ten cases with consecutive tracings, the different pattern and rhythm of electromyograms between the sphincter of ODDI and the duodenum were also confirmed. It was possible, from our results, to speculate that the functional independence of the sphincter of ODDI from the duodenal wall muscles was in existence.