Prospective Evaluation of Residual Bile Duct Stone by Peroral Cholangioscopy After Conventional ERCP
Prospective Evaluation of Residual Bile Duct Stone by Peroral Cholangioscopy After Conventional ERCP
Gallstone disease affects over 20 million Americans. Among patients with gallbladder disease,
 the prevalence of choledocholithiasis (stones in the bile duct) is estimated to be 10-20%.
 Endoscopic retrograde cholangiopancreatography (ERCP) is considered the standard of care for
 removing stones in the bile duct utilizing a variety of conventional methods including
 biliary sphincterotomy, sphincteroplasty, extraction balloon, retrieval basket, and
 mechanical lithotripsy. After removal of stones from the bile duct, an occlusion
 cholangiogram is usually performed to confirm complete bile duct clearance. However,
 cholangiogram can miss residual stones in 11- 30% of cases - especially in the setting of a
 dilated bile duct, large stones, severe pneumobilia, juxtapapillary diverticulum, primary
 sclerosing cholangitis, and after lithotripsy (mechanical, electrohydraulic, or laser). The
 approach to patients with choledocholithiasis requires careful attention because missed bile
 duct stones can cause recurrent biliary symptoms, pancreatitis, cholangitis, and has
 significant cost implication with the need for repeat imaging and/or procedures.
Peroral cholangioscopy (POC) provides direct visualization of the bile duct during ERCP and
 its benefits are well documented in numerous published studies. POC has been described for
 therapy of difficult to remove biliary stones utilizing electrohydraulic lithotripsy or laser
 lithotripsy with success rates of >90%. POC has also been used for evaluation of
 indeterminate filling defects and to assess for residual stones missed with cholangiogram. In
 a multicenter study evaluating POC for a variety of indications, 11% (7/66) of patients had
 bile duct stones identified only by POC that were missed on ERCP. In a study of patients with
 primary sclerosing cholangitis, 30% (7/23) of patients were found to have stones with POC
 that were missed with cholangiography. Takao et al. assessed residual bile duct stones found
 with POC in comparison to balloon-cholangiography; they found that 24% (26/108) of patients
 had residual stones seen with POC that were missed with balloon-cholangiography.

 Although POC has been available for over thirty years, it has not become a widespread
 technique due to the fact that traditional cholangioscopes are fragile, cumbersome to use,
 and usually require two endoscopists to perform the procedure. A recent single operator
 semi-disposable cholangioscope, SpyGlass (Boston Scientific, Natick, Massachusetts), has
 addressed those concerns and has been shown in a studies to be a useful tool in visualizing
 the bile ducts and performing therapeutic maneuvers for biliary stones. Both ERCP and
 Cholangioscopy are standard of care procedures to treat gall stones.

 The primary goal of the study is to assess if POC will enhance the diagnostic yield in the
 detection of residual biliary stones that are missed during conventional ERCP. Residual bile
 duct stones can especially be seen in the setting of bile duct dilation, history of recurrent
 abnormal liver function tests, and after lithotripsy (mechanical, electrohydraulic, or
 laser). Missed biliary stones can lead to recurrent biliary symptoms, pancreatitis, and
 cholangitis. POC after conventional ERCP can be a useful diagnostic tool to confirm complete
 extraction of bile duct stones, and thus lead to decreased morbidity and decreased cost by
 avoiding unnecessary tests and repeat procedures.
Inclusion Criteria:

 1. Patient receiving ERCP as standard of care for suspected or documented
 choledocholithiasis as assessed by one or more of the following:

 1. Abnormal imaging on ultrasound, endoscopic ultrasound (EUS), CT scan, or MRCP
 suggestive of choledocholithiasis

 2. Clinical signs and symptoms suggestive of choledocholithiasis such as jaundice,
 abdominal pain, pruritis, pancreatitis, and/or cholangitis

 3. Abnormal liver function tests suggestive of choledocholithiasis (eg: serum
 bilirubin > 1.5 and/or elevated alkaline phosphatase levels)

 2. In addition to one or more of the above inclusion criteria, patient must also satisfy
 one or more of the following:

 1. Mechanical lithotripsy, electrohydraulic lithotripsy, or laser lithotripsy
 performed for therapy of bile duct stones.

 2. Bile duct > 12mm on prior tests (any portion of duct)

 3. History of recurrent abnormal LFTs with negative cholangiogram.

 4. Positive EUS or MRCP for biliary stones with a negative cholangiogram

 Exclusion Criteria:

 1. Patients less than 18 years of age.

 2. Patients not undergoing ERCP as their standard of care.

 3. Patients who had the following surgeries - Billroth II surgery, Roux-en-Y Gastric
 bypass surgery, and Whipple's surgery.