BILIARY, PANCREATIC, AND SPHINCTER OF ODDI ELECTRICAL AND MECHANICAL SIGNALS RECORDED DURING ERCP

Measurements of biliary tract motility have focused on radiologic and pressure measurements to quantify biliary motility rather than measure ments of electrical activity of the biliary tract. We previously repor ted the recording of biliary electrical signals during ERCP and now re port on the continued development and validation of a system to measur e biliary tract electrical activity as well as biliary mechanical acti vity. In 26 patients presenting with a variety of clinical indications , we recorded measurements of electrical activity from the common bile duct sphincter (16 patients), pancreatic duct sphincter (eight patien ts), and/or sphincter of Oddi (eight patients). Electrical recordings were performed with a specially modified ERCP catheter, using two circ ular electrodes as well as a custom catheter that measured both electr ical and mechanical activity. Electrical activity of the biliary tract was successfully recorded in 25 of 26 patients (96%), including the c ommon bile duct sphincter (16 patients, 62%), pancreatic duct sphincte r (eight patients, 31%) and sphincter of Oddi (eight patients, 31%). A long with the electrical recordings, common bile duct sphincter mechan ical activity was recorded in 12 patients (67%), pancreatic duct sphin cter mechanical activity in six patients (33%), and sphincter of Oddi mechanical activity in six patients (33%). Frequency analysis of elect rical signals revealed a mean frequency (cycles/min) of 4.7 +/- 0.5 in the common bile duct sphincter, 4.1 +/- 0.6 in the pancreatic duct sp hincter, and 4.9 +/- 0.7 in the sphincter of Oadi. Phasic mechanical f requency in cycles per minute was recorded at a frequency of 4.8 +/- 0 .5 in common bile duct sphincter, 4.0 +/- 0.6 in pancreatic duct sphin cter, and 5.3 +/- 0.9 in sphincter of Oddi. Tonic pressure (averaged 1 2.1 +/- 1.5 mm Hg) in common bile duct sphincter, 12.4 +/- 1.4 mm Hg i n pancreatic duct sphincter, and 15.0 +/- 5.1 mm Hg in sphincter of Od di. Analysis of wave form propagations (noted as percentage antegrade, retrograde, or indeterminant) revealed 50% antegrade, 23% retrograde, and 27% indeterminant). One patient was recorded on two occasions via ERCP; the same patient had an Intraoperative recording; All three rec ordings showed similarities. We conclude that measurements of biliary, pancreatic, and sphincter of Oddi electrical and mechanical activity are feasible and can be done as part of ERCP. There was good correlati on between biliary tract electrical and mechanical events and differen t wave form characteristics were noted for different parts of the bili ary ti ee. Further studies are warranted to evaluate the potential use fulness of measurement of biliary tract electrical activity, and to co nfirm its correlation with mechanical events in the pancreato-biliary tree.