Sphincter of Oddi dysfunction and unexplained abdominal pain: Clinical and manometric study

Abstract

Unexplained, biliary-type abdominal pain is often attributed to an abnormal pressure profile of the sphincter of Oddi. In spite of this assumption, the true prevalence of this type of motor dysfunction among cholecystectomized patients with unexplained abdominal pain is not known. We studied 64 postcholecystectomy patients who were thought to have sphincter of Oddi dysfunction. Radiologically, other than a dilated common bile duct in some, they had no anatomic derangement of their pancreatobiliary tract to explain their symptoms. They were categorized into three groups on the basis of four objective findings suggesting abnormal biliary emptying mechanism. Basal sphincter of Oddi pressure, frequency of phasic contractions, and proportion of retrograde, contractions were determined in all patients. Twenty-six (41%) of the patients demonstrated at leas one motor abnormality, 16 (25%) had two, and 10 (16%) had all three abnormal parameters. The pressure profile of the sphincter was normal in 38 or 59% of the patients. Seventy-three percent (73%) of the patients in group I, who had three or four of the objective findings for sphincter of Oddi dysfunction, demonstrated at least one motor abnormality. Sixty percent of this group demonstrated an increased basal sphincter of Oddi pressure. On the other hand, only 19% of the patients in group III, who had none of the objective findings, revealed a motor abnormality. Increased basal sphincter of Oddi pressure, was noted in 7% of this group. We conclude that, sphincter of Oddi dysfunction, as diagnosed manometrically, explains the recurrent biliary type abdominal pain in a minority of patients. Moreover, presence of objective findings suggestive of a compromised biliary emptying significantly increases the diagnostic yield of manometry. In our opinion, these criteria must be utilized for selection of the patients for sphincter of Oddi manometry.