COMPARING BALLOON DIAMETER ON PERFORMING ENDOSCOPIC PAPILLARY BALLOON DILATATION WITH ISOSORBIDE DINITRATE DRIP INFUSION FOR REMOVAL OF BILE DUCT STONES

Abstract

Background: Endoscopic papillary balloon dilatation (EPBD) is one of the methods to remove bile duct stones. EPBD might preserve the function of the sphincter of Oddi despite the potential risk of acute pancreatitis. There are only a few reports of EPBD reducing the risk of acute pancreatitis and, at same time, preserving the function of the sphincter of Oddi.Methods: We performed EPBD for bile duct stone removal in 60 patients using two balloons with different diameters. Patients were randomized to EPBD with a 6 mm balloon (n = 30) or an 8 mm balloon (n = 30). In both groups, isosorbide dinitrate (ISDN) was infused in a rate of 5 mg/h while low pressure EPBD were being performed. The pressure of the sphincter of Oddi was observed before and after the EPBD procedures. Also, serum amylase level after EPBD was observed for both groups.Results: Serum amylase level of the 6 mm group was significantly higher than that of the 8 mm group (P < 0.05). Acute pancreatitis occurred in two patients ( 6.7%) in the 6 mm group whereas no case was observed for the 8 mm group. The rates of duct clearance were 93% in the 6 mm group and 100% in the 8 mm group. Stone removals were difficult in seven cases with 6 mm balloon dilatations due to the narrow orifices of the papilla. In the 6 mm group, there was no significant difference between the basal sphincter of Oddi pressure (BSOP) and the phasic sphincter of Oddi pressure (PSOP) before and after EPBD. However in the 8 mm group, the BSOP observed after the EPBD procedure was significantly higher than BSOP before the treatments. Within this group, BSOP values after EPBD were preserved by approximately 80% of the BSOP values before the treatments. In contrast, there was no significant difference in PSOP before and after the treatments. Regarding the stone numbers, no significant difference was observed in BSOP before and after the treatments for the 6 mm group with less than two stones. Also, as for stone size, no significant difference was observed in BSOP before and after the treatments for the 6 mm group with stones of less than 6 mm in diameter.Conclusion: We are now conducting EPBD with ISDN infusion using a 6 mm balloon for a patient who has less than two stones with size not exceeding 6 mm in diameter. An 8 mm balloon is used for a patient with more than two stones or a stone greater than 6 mm in size.