Endoscopic papillotomy and papilloplasty: Effects on sphincter of Oddi functionality and outcomes

Structural or functional abnormality of sphincter of Oddi: an important factor for the recurrence of choledocholithiasis after endoscopic treatment

A high recurrence rate is undesirable after treatment of common bile duct (CBD) stones. A major risk factor identified for recurrence is that invasive techniques, including surgical or endoscopic treatments, will impair the biliary tract system either by direct incision of the CBD or by cutting or dilating the ampulla of Vater. During endoscopic treatment, two main assisted methods for lithotomy, sphincterotomy and papillary balloon dilation, can result in different degrees of damage to the structure and function of the sphincter of Oddi (SO), contributing to slowing of biliary excretion, cholestasis, biliary bacterial infection, and promotion of bile duct stone recurrence. In this review, the relationship between endoscopic lithotomy and structural impairment or functional abnormality of the SO will be summarized, and their relationship with the recurrence of CBD stones will also be analyzed. Further improvement of these endoscopic methods or exploration of some novel methods, such as endoscopic endoclip papilloplasty, temporary insertion of a self-expandable metal stent, and combined application of peroral cholangioscopy, may aid in providing more appropriate treatment for patients with choledocholithiasis, repair or protect the function and structure of SO, reduce or prevent the recurrence of bile duct stones, and improve patient outcomes.

The radiation doses and radiation protection on the endoscopic retrograde cholangiopancreatography procedures

Although many interventions involving radiation exposure have been replaced to endoscopic procedure in the gastrointestinal and hepatobiliary fields, there remains no alternative for enteroscopy and endoscopic retrograde cholangiopancreatography (ERCP), which requires the use of radiation. In this review, we discuss the radiation doses and protective measures of endoscopic procedures, especially for ERCP. For the patient radiation dose, the average dose area product for diagnostic ERCP was 14-26 Gy.cm², while it increased to as high as 67-89 Gy.cm² for therapeutic ERCP. The corresponding entrance skin doses for diagnostic and therapeutic ERCP were 90 and 250 mGy, respectively. The mean effective doses were 3- 6 mSv for diagnostic ERCP and 12-20 mSv for therapeutic ERCP. For the occupational radiation dose, the typical doses were 94 μGy and 75 μGy for the eye and neck, respectively. However, with an over-couch-type X-ray unit, the eye and neck doses reached as high as 550 and 450 μGy, with maximal doses of up to 2.8 and 2.4 mGy/procedure, respectively.A protective lead shield was effective for an over couch X-ray tube unit. It lowered scattered radiation by up to 89.1% in a phantom study. In actual measurements, the radiation exposure of the endoscopist closest to the unit was reduced to approximately 12%. In conclusion, there is a clear need for raising awareness among medical personnel involved endoscopic procedures to minimise radiation risks to both the patients and staff.