The reported incidence of sphincter of Oddi dysfunction following orthotopic liver transplantation has ranged from 3% to 7%. If sphincteric dysfunction is unrecognized, therapy may be inappropriate; when recognized, extensive surgery may be required. To prospectively identify patients with sphincteric dysfunction, we performed sphincter of Oddi motility studies through the t-tube tract three months after transplantation. Baseline sphincter motility and response to intravenous cholecystokinin were evaluated. The results of 10 subjects are reported; nine had normal basal sphincter pressure (16 +/- 5.8 mm Hg), and all had normal frequency (3.6 +/- 1/min), amplitude (86 +/- 31 mm Hg), and duration (4.5 +/- 1 sec) of phasic contractions. One subject had an elevated basal pressure (47 mm Hg). All, including the subject with elevated basal pressure, demonstrated a normal response to intravenous cholecystokinin with significant inhibition of phasic contraction frequency and amplitude. We demonstrate that simultaneous studies of the sphincter and duodenum can be obtained via the t-tube tract, providing the opportunity for prospective evaluation of sphincteric function. We conclude that sphincter of Oddi function usually remains normal following liver transplantation with choledochocholedochostomy.