[Do ultrasound parameters allow diagnosis of biliary sphincter of Oddi dysfunction?]

A noninvasive test to prove sphincter of Oddi dysfunction is desired, because endoscopic manometry is technically demanding and not without risks.

40 consecutive patients (n = 20 patients with, and n = 20 patients without enzymatic cholestasis) with suspected SOD were investigated both by ultrasonography (US; 3.5 MHz) and by endoscopic manometry. SOD was suspected at US if the extrahepatic bile duct diameter was > or = 9 mm and a further increase (at least > 0.5 mm) was observed after intravenous ceruletide (0.3 micrograms/kg b.w.). SOD was verified manometrically by a sphincter of Oddi basal pressure > or = 40 mmHg. Endoscopic sphincterotomy was performed if SOD was diagnosed by manometry. Thereafter, all patients were enrolled in a prospective follow-up (median: one year).

At US SOD was suspected in eleven of 20 patients with cholestasis. SOD was confirmed manometrically in all of them but also in two further patients (13 of 20 patients with proven SOD). After EST twelve of 13 patients remained free from biliary symptoms. In the 20 patients without cholestasis SOD was suspected at US in five patients only. However, endoscopic manometry revealed SOD in eleven of 20 patients and proved sonographically presumed SOD in only three of five patients. After EST only three of eleven patients remained asymptomatic during follow-up (p < 0.05 vs. patients with cholestasis). Clinically important side effects were not observed after ceruletide administration, whereas postmanometry pancreatitis was observed in three of 40 patients.

In patients with recurrent symptoms after cholecystectomy and enzymatic cholestasis SOD was reliably diagnosed by ultrasonography (sensitivity: 85%, specificity: 100%), and this finding may guide endoscopic sphincterotomy.