Continuous 99mTc-HIDA infusion as a method for measuring duodenogastric reflux.

The continuous 99mTc-HIDA infusion test is presented as a method for measuring duodenogastric reflux as well as for studying biliary elimination of the compound when it is administered by constant intravenous infusion. Thirty patients were studied: (a) ten patients with a T tube placed in the biliary tree were used to study the elimination of 99mTc-HIDA in the bile; (b) ten normal subjects were used as a control group; and (c) ten patients were studied who had undergone Billroth I gastrectomy for peptic ulceration. Studies of subjects in groups (b) and (c) were used to assess duodenogastric reflux by this test, correlating it with the measurement of bile acids in gastric juice. When 99mTc-HIDA was administered by constant intravenous infusion it resulted in an increased elimination in bile for the first 80-100 min, and the concentration in bile then remained relatively constant for the rest of the test. With respect to the duodenogastric reflux study group, reflux rates in the patients who had been operated on were higher than those in the control group, with statistically significant differences. Minimum reflux rates were found in the normal subjects. Assessment of reflux by 99mTc-HIDA correlated closely with the results of bile acid concentrations in Billroth I patients (r = 0.75, P less than 0.001) and control subjects (r = 0.85, P less than 0.001). Our results demonstrate that continuous 99mTc-HIDA perfusion is a useful, accurate and objective method for measuring duodenogastric reflux.