ObjectiveTo explore the efficacy and safety of endoscopic sphincterotomy (EST) in the treatment of sphincter of Oddi dysfunction (SOD).MethodsThe clinical data of 95 cases of SOD treated with EST in Affiliated Hospital of Guizhou Medical University and Tumor Hospital Affiliated to Guizhou Medical University from January 2014 to January 2019 were collected retrospectively, to evaluate and analyze the effect of clinical diagnosis and treatment of EST on SOD patients.ResultsAmong 95 SOD patients, 86 were biliary type SOD and 9 were pancreatic type SOD. All 95 patients underwent EST. The Verbal Rating Scales-5 (VRS-5) scores before EST were all 3 or 4 points, and the VRS-5 scores decreased after treatment in each type of SOD patients, the difference were all statistically significant (P<0.05). After treatment, levels of ALT, AST, ALP, TBiL, and DBiL in biliary type SOD Ⅰ and type Ⅱ were significantly lower than before (P<0.05); ALT, AST, ALP, GGT, and blood and urine amylase in patients with pancreatic type SOD after EST were significantly decreased than before (P<0.05), and the biochemical indicators of patients with SOD Ⅲ before and after treatment did not change significantly (P>0.05). After EST treatment, 70 (81.4%) of the 86 patients with bile type SOD showed significant effect, and 10 patients (11.6%) were effective, with an overall effective rate of 93.0% (80/86). Among the 16 patients with bile type SOD Ⅰ, 14 patients (87.5%) received significant effect, and 1 patient (6.3%) was effective, with an overall effective rate of 93.8% (15/16). That 51 patients with bile type SOD Ⅱ received EST, of which 43 patients (84.3%) were significantly effective and 6 patients (11.8%) were effective, with an overall response rate of 96.1% (49/51). Among the 19 patients with bile type SOD Ⅲ treated with EST, 13 patients (68.4%) were significantly effective and 3 patients (15.8%) were effective, with the overall effective rate was 84.2% (16/19). There was no statistically significant difference in the overall effective rate of patients with 3 types of biliary type SOD patients (P>0.05). Endoscopic treatment was effective in all 9 cases of pancreatic type SOD, with an overall effective rate of 100%. There were 5 patients (5.3%) of acute pancreatitis after EST, and no bleeding, perforation, cholangitis or other complications occurred. All patients were interviewed for 1 to 5 years postoperatively, the median follow-up duration was 2.33 year, during the follow-up period, nolong-term complications such as Oddi sphincter restenosis and cholangitis caused by intestinal bile reflux.ConclusionESTis a minimally invasive, safe, and effective treatment for SOD in patients with bile duct type and pancreatic duct type, and it is an important treatment for SOD.