A pilot randomized trial to study the success rate of early precut fistulotomy and its effect on radiation dose in patients with difficult biliary cannulation

Background: Role of precut fistulotomy in reducing fluoroscopy time and the radiation dose in difficult selective biliary cannulation is unknown. Methods: We performed a randomized trial where patients with difficult biliary cannulation were randomized into 2 groups: early precut fistulotomy (precut five minutes after failed standard biliary cannulation) or late precut fistulotomy (precut fifteen minutes after failed standard biliary cannulation). We compared the success rates of selective biliary cannulation, fluoroscopy time, radiation dose, complication rates, need for repeat endoscopic retrograde cholangiography (ERC) and need for other interventions Results: Of the 130 eligible patients screened, 40 patients were randomized. The technical success was comparable between early and late group. The fluoroscopy time and radiation dose were significantly less in the early group [4 minutes (3, 6) vs 15 minutes (8, 28), p=0.001] and [1.35 mGy (0.90, 1.63) vs 2.40 mGy (1.58, 3.25), p=0.010] respectively. In the late group, 60% required need for rescue precut fistulotomy. One patient from late group developed post ERC pancreatitis while 1 from early group developed perforation. Three needed other interventions due to failed second attempt. Conclusion: Early precut fistulotomy has comparable technical success and reduces the radiation dose as compared to late precut fistulotomy for difficult biliary cannulation.