Evaluation of gallbladder function before and after gastrectomy using a double-isotope method.

The motor function of the gallbladder after partial distal gastrectomy for gastric carcinoma (Billroth-I reconstruction) and its relationship to the motor function of the stomach was investigated using a double-isotope method. In this method, [99mTc]N-54-pyridoxyl-5-methyltryptophan ([99mTc]PMT) was utilized as a tracer for the biliary tract and [111In]diethyl-triaminopontacetic acid ([111In]DTPA) mixed with a liquid test meal was used as a tracer for the digestive tract. Gastric emptying half-time (GET1/2) was measured, since this was used historically as the physiologic indicator of gallbladder contractile stimulus. The volume of test meal that emptied from the stomach into the duodenum per minute (VOL/MIN) was measured, as was the gastric emptying duration (GED). A series of gallbladder emptying phenomena were analyzed using three different criteria: gallbladder emptying half-time (GBET1/2), retention rate of bile in the gallbladder (RR), and the start of gallbladder bile ejection into the duodenum after ingestion (TL: time lag). While GET1/2 was reduced (P < 0.01) and VOL/MIN was increased (P < 0.01) after gastrectomy, GED was shortened remarkably (P < 0.01). GBET1/2 showed no significant change, RR increased (P < 0.05), and TL was prolonged (P < 0.01). The postoperative dysfunction of the gallbladder was caused by the short and intense stimulus on the biliary tract during the duodenal phase and by intraoperative injury to the innervation of the gallbladder. In particular, the hepatic branch of the left vagus nerve was injured during the right paracardiac lymph node dissection performed as a component of the radical gastrectomy.