Endoscopic sphincter of Oddi manometry with a portable electronic microtransducer system: comparison with the perfusion manometry method and routine clinical application.

BACKGROUND AND STUDY AIMS: Endoscopic perfusion manometry (PM) of the sphincter of Oddi (SO) requires expensive equipment which is relatively large and uncomfortable to handle in the endoscopic retrograde cholangiopancreatography (ERCP) setting. Furthermore, the volume load of the biliopancreatic system may contribute to the increased risk of pancreatitis after SO manometry.

PATIENTS AND METHODS: The newly developed small and lightweight microtransducer system consists of a portable data-logger with integrated online display which is connected to a 4-Fr manometry probe. The manometry catheter is inserted endoscopically into the biliopancreatic system via a 7-Fr Teflon sheath. SO motility can be observed online on the display but the data can also be stored for later analysis on a personal computer (PC). To validate the new method, 15 patients with suspected biliary SO dysfunction underwent both PM as well as microtransducer manometry (MTM) in randomized order. Thereafter, 50 consecutive patients with suspected biliary or pancreatic SO dysfunction were investigated solely by MTM.

RESULTS: PM was possible in 13 of 15 cases whereas MTM could be performed in all 15 patients. The basal SO pressure tended to be lower (approximately 5 mmHg) when measured with the MTM, compared with the PM method, but there was a significant and nearly linear correlation between the basal SO pressures obtained by both methods (r=0.98, P<0.001). SO dysfunction was diagnosed in the same five patients using both methods. Furthermore, the parameters of phasic SO motility were highly comparable when measured by MTM and PM. MTM was carried out successfully in 49 of 50 patients and only one MTM probe was used for all examinations, without malfunction. The endoscopist was able to diagnose SO dysfunction (by immediate observation of SO motility on the display) in 19 of 20 patients (when compared with the later PC analysis) and SO motility was judged correctly as normal in the remaining 29 cases. MTM was repeated in five patients with SOD 1-6 weeks after the first examination and the manometric findings were confirmed in all cases. Mild postmanometry pancreatitis was observed in only one of 49 patients (2%).

CONCLUSIONS: Endoscopic MTM is a reliable, safe, very easy to handle, and low-cost alternative for the clinical assessment of SO motility.