Comparison of sphincter of Oddi manometry, fatty meal sonography, and hepatobiliary scintigraphy in the diagnosis of sphincter of Oddi dysfunction

Background. Sphincter of Oddi dysfunction (SOD) afflicts approximately 1% t o 5% of patients after cholecystectomy. The diagnostic standard for SOD is sphincter of Oddi manometry (SOM), a technically difficult, invasive test t hat is frequently complicated by pancreatitis. A sensitive and accurate non invasive imaging modality is thus:needed for the diagnosis of SOD. Quantita tive hepatobiliary scintigraphy (HBS) and fatty meal sonography (EMS):are f requently used for this purpose, but results vary. This study compared SOM, HBS, and EMS in the diagnosis of SOD in a large group of patients. Methods: Three hundred four consecutive patients after cholecystectomy (38 men, 266 women, age 17-72 years) suspected to have SOD were evaluated by SO M 1 FMS, and HBS. SOM was considered abnormal if any of the following were observed: (1) increased basal pressure (greater than 40 mm Hg), (2) increas ed phasic activity with amplitude greater than 350 mm Hg, (3) frequency of contractions greater than 8 per minute, (4) greater than 50% of propagation sequences retrograde, and (5) paradoxical response to cholecystokinin. FMS was considered abnormal if ductal dilation was greater than 2 mm at 45 min utes after fatty meal ingestion. Quantitative HBS was performed with sequen tial images obtained every 5 minutes for 90 minutes to monitor excretion of the radionuclide. Time-to-peak, halftime, and downslope were calculated ac cording to predetermined ranges. Results: A diagnosis of SOD was made in 73 patients (24%) by using SOM as t he reference standard. HBS was abnormal in 86 whereas EMS was abnormal:in 2 2 patients. A true-positive result was obtained in 15 patients by EMS and 3 6 patients with HBS. EMS and HBS gave false-positive results, respectively, in 7 and 50 patients. Sensitivity of EMS was 21% and for HBS 49%, whereas specificities were 97% and 78%, respectively. EMS, HBS, or both were abnorm al in 90% of patients with Geenen-Hogan Type I SOD, 50% with Type II, and 4 4% of Type III. Of the 73 patients who underwent sphincterotomy, 40 had a l ong-term response. Of those with SOD, 11 of, 13 patients (85%) with an abno rmal HBS and EMS had a good lon g-term response. Conclusions: In this series, the largest reported to date, correlation of F MS and HBS with SOM in the diagnosis of SOD was poor. When HBS and EMS are used together, a slight increase in sensitivity can be expected. The accura cy of EMS and HBS in the:diagnosis of SOD decreases across the spectrum fro m Type I to Type Ill SOD. EMS and HBS, nonetheless, may by of assistance in predicting long-term response to endoscopic sphincterotomy in patients wit h: elevated sphincter of Oddi basal pressure.