Table 1. Demographic characteristics of the patients Characteristics Number of patients Male/female, n 39/7 Mean age, years (range) 54.2 (29-77) EPST alone/EPST with EST, n (%) 19 (41.3)/27 (58.7) Location of EPST, n (%) Major papilla 42 (91.0) Minor papilla 4 (9.0) Successful EPST, n (%) 44 (95.7) EPST, endoscopic pancreatic sphincterotomy; EST, endoscopic biliary sphincterotomy. Elton et al. reported that the use of a pancreatic stent and endoscopic nasopancreatic drainage (ENPD) following EPST could reduce the incidence of complications [9]. According to other studies, however, the usefulness of ENPD is questionable [10]. Very few recent studies [10] have reported on the safety and complications of EPST performed by a single physician at a single center. We examined the indications, complications, and safety of EPST, and compared the incidence of complications in cases when a pancreatic drainage procedure was per- formed. In particular, we compared procedures in which EST following EPST was performed and those in which EPST was performed alone. METHODS Patients Of 2,313 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) at Hanyang University Medical Center between January 1996 and March 2008, 46 patients who underwent EPST were enrolled. These patients consisted of 39 men and 7 women (mean age 54.6 and 52.4 years, respectively; Table 1). Methods EPST was performed for either the main pancreatic duct or the accessory pancreatic duct, or for the main pancreatic duct together with the accessory pancreatic duct. For endoscopy, a duodenoscopy was performed. Based on the location and type of orifice, the incision was made using a cutting and coagulation blended current, with a standard pull-type papillotome or needle knife. During the EPST procedure, midazolam, pethidine, and Buscopan were intravenously infused as needed. For main pancreatic sphincterotomy, a 5-10 mm incision was made Joo YW, et al. Endoscopic pancreatic sphincterotomy 191 in a 12-2 o’clock direction, along the axis of the main pancreatic duct from the opening of the pancreatic duct. An incision was made up to the upper margin of the hood- ing fold [11]. For accessory pancreatic duct incisions, the location of the accessory pancreatic duct was confirmed using a specialized catheter. The incision was attempted by inserting a papillotome using a 0.018-inch guidewire. Otherwise, the incision was made using a needle knife papillotome [11]. In patients with severe pancreatic stenosis, a pancreatic stent and ENPD were inserted, if necessary. All patients were given a full explanation about the pro- cedure and provided written informed consent. Treatment success in EPST was defined as cases in which the opening of the pancreas could be successfully approached following the procedure. Pancreatitis was defined as cases in which serum amylase exceeded three times the normal value in the presence of epigastric pain, even 24 hours after the procedure. Bleeding was defined as cases in which a blood transfusion was carried out after hemoglobin decreased by more than 2 g/dL within a day after the procedure. The definitions and severity of other complications were based on the classification system of Cotton et al. [12] Statistical analysis Statistical analyses were performed using SPSS for windows, version 12.0 (SPSS inc., Chicago, IL, USA). A cross-tabulation was carried out using the chi-square test and the Mann-Whitney U-test. P values <0.05 were deemed to be statistically significant. RESULTS In the 46 patients, the success rate of EPST was 95.7% (44/46). Two cases of failure occurred, both in accessory pancreatic duct dissections. A main pancreatic sphinc- terotomy was performed in 42 cases (91.3%), while an accessory pancreatic sphincterotomy was carried out in four cases (8.7%, Table 1). The causative factors for chronic pancreatitis requiring EPST involved alcoholism (63%) and unknown causes (21%). Anatomical anomalies, such as anomalous union of the pancreaticobiliary duct (AUPBD) and pancreatic divisum, accounted for the other 16% (data not shown). Indications for EPST The most frequent diagnostic indication (26 cases)