Madura et al1 report their large experience over 24 years with surgical sphincteroplasty for presumed sphincter of Oddi dysfunction (SOD) or accessory papilla stenosis with pancreas divisum. Their patients were selected for operation by clinical judgment, principally based on pain (100%), because only 25% had objective evidence of pancreatitis. They attempted to validate this judgment post hoc by intraoperative assessment of flow and pressure in the bile duct (at least in those with SOD). Overall, 82% of patients had an excellent or good outcome (no criteria given) after follow-up of at least several months if their symptoms were totally relieved.
Andrew L. Warshaw. Surgical Sphincteroplasty in 446 Patients—Invited Critique. Arch Surg. 2005;140(5):513. doi:10.1001/archsurg.140.5.513