Transduodenal sphincteroplasty (TS) for abnormalities of the biliary and pancreatic duct sphincters is an operation that has generated a great deal of study and interest by both gastrointestinal endoscopists and surgeons. The reason for this attraction is that if true, these syndromes validate a fundamental pathophysiologic concept related to restrictions of flow in a secretory organ. For the pancreas, this involves either a developmental malformation resulting in an inadequately sized sphincter (pancreas divisum), or an acquired sphincter stenosis due to passage of gallstones and/or inflammation [sphincter of Oddi dysfunction (SOD)] both leading to pancreatic-type pain or recurrent episodes of acute pancreatitis. For the liver, the acquired sphincter stenosis, presumably again from passage of gallstones and debris, results in biliary-type pain and liver function test elevations. In both of these situations, the secretory organ somehow ascertains this flow restriction and responds with inflammation (pancreatitis, hepatitis) and symptoms experienced in the organism as pain. Sphincter enlargement of the pancreatic or biliary orifice, or both, either through endoscopic sphincterotomy (ES) or transduodenal sphincteroplasty (TS) should alleviate this flow restriction and its attendant organ response leading to pain relief. Despite this appealing theory, the level of scientific evidence to support either TS or ES for abnormalities of the biliopancreatic sphincters remains meager at best (Level C, Level II-3), certainly not sufficient to establish a causal relationship between stenosis and symptoms. Unfortunately, both medical and surgical data on this topic consist almost exclusively of small case series containing fundamental methodologic flaws including referral bias, lack of blinding, absence of a control group, and short clinical follow-up. As there are no animal models of spontaneously occurring sphincter dysfunction to investigate, all data is derived from humans, which to date, has been carried out without a proper placebo-controlled population. Despite these limitations, there still exists a substantial body of literature reporting decreasing pain scores, reduction in episodes of acute pancreatitis, and reduction in recurrent hospitalizations, in approximately three-quarters of selected patients treated by either
ES or TS, a level of success that cannot be easily be ignored. Perhaps the key word in the above sentence is “selected” as it is clear that there are substantial overlap between symptoms of patients with hypertensive pancreatic or biliary sphincters and those with chronic pancreatitis, alcohol or narcotic addiction, or visceral hypersensitivity syndromes.

Historically, early operative series of TS reported encouraging results in effective symptom control with low associated morbidity and mortality rates. Advances in endoscopic imaging and instrumentation promoted the development of ES, a minimally invasive technique that has supplanted operative TS in the majority of patients with pancreatic or biliary sphincter abnormalities. The ability to manometrically measure biliary and pancreatic duct sphincter pressures endoscopically has brought about the convergence of both diagnosis and treatment within one procedure such that most patients with SOD or pancreas divisum are now treated by ES at the time of their initial diagnosis. This synchronous diagnostic-therapeutic endeavor, while efficient, discourages collaboration and randomization possibly contributing to the slow progress in this field. As another consequence of this efficiency, only a small percentage of patients are now considered candidates for operative TS: Those who have failed one or more prior ESs or those with anatomic abnormalities limiting the endoscopic access to their major or minor papilla (post-bariatric or gastric surgery). From a surgeon’s perspective, this results in the paradox that while the total number of patients having TS has declined, the complexity level of each operation (reoperative field, prior gastric surgery, strictured ES) has increased. In this situation, both experience and sound clinical judgment are paramount in achieving optimal therapeutic outcomes. As a byproduct of this endoscopic selection bias and declining referral patterns, the surgical literature over the last decade has focused on improving the indications and patient selection criteria for TS in an effort to maximize long-term benefits. For the purpose of our discussion in this chapter, there are currently three solid indications for TS: