147 Holmium-YAG LASER Lithotripsy in the Treatment of Biliary Calculi Using Intraductal Endoscopy (SPYGLASS®) in Adolescent Patients Douglas S. Fishman*, Kimberly a. Mackey, Dang Nguyen, Bethany J. Slater, David Wesson, Sheena Pimpalwar, Isaac Raijman Pediatric Gastroenterology, Texas Children’s Hospital, Houston, TX; Digestive Associates of Houston, Houston, TX; Michael E. Debakey Department of Surgery, Baylor College of Medicine, Houston, TX; Department of Pediatric Radiology, Texas Children’s Hospital, Houston, TX Background: Pediatric biliary disease has been increasing over the last decade with up to a 30% rate of complicated biliary obstruction reported. Adult ERCP data suggests up to 10% of biliary stones may need advanced removal techniques such as electrohydraulic or laser lithotripsy. We have previously described our experience using Holmium-YAG Laser in an adult population with excellent safety profiles. We now report our experience using Holmium-YAG laser with choledochoscopy in a series of adolescent patients. Methods: A single-center retrospective case series from November 2011 to November 2012. Four patients with large/complex biliary stones underwent intraductal endoscopy with Spyglass® (Boston Scientific, Natick, MA) guided Holmium-YAG laser (Dornier, Phoenix, AZ) lithotripsy using a Slimline® disposable 365 micron laser probe (Lumenis, Sunnyvale, CA). The laser fiber was placed close to the stone and repeat fragmentation was repeated as needed. Results: Median age was 17 years old (range 16-17) with two females. Standard ERCP was performed in 3 of 4 patients, with the additional case performed through previously established percutaneous biliary access in a patient with Roux-en-Y anatomy. 2 cases were planned electively, and all four were done with general anesthesia. Indications were for complex or large biliary lithiasis in all four patients, including 1 cystic duct stone (Figure 1) and 1 with a common hepatic duct stone in a patient with a choledochal cyst. All 3 ERCP had a sphincterotomy / biliary stent. Staged therapy due to access in the patient with a percutaneous drain was planned. Stone ablation was successful in all four cases, with complete stone destruction and removal in 50%, with partial stone fragmentation in the remaining. (Image 2). There were no procedural complications. Conclusions: Holmium-YAG laser usage in adolescent patients is safe and effective using both ERCP and PTC. Lithotripsy is feasible in the common bile duct, cystic duct and via PTC. As in the adult population, staged procedures may be necessary. Further studies are needed to assess the usage of this technology in pediatric patients. 188 Boston Bowel Preparation Scale Scores Provide a Standardized Definition of “Adequate” for Describing Bowel Cleanliness Audrey H. Calderwood*, David a. Lieberman, Judith R. Logan, Michael Zurfluh, Brian C. Jacobson Gastroenterology, Boston University Medical Center, Boston, MA; Gastroenterology, Oregon Health Sciences University, Portland, OR; Medical Informatics, Oregon Health Sciences University, Portland, OR Background: Establishing a threshold of bowel cleanliness below which colonoscopies should be repeated is important, yet there are no standardized definitions for “adequate” or “adequate to exclude polyps 5 mm in size.” We hypothesized that Boston Bowel Preparation Scale (BBPS) scores could provide a way to standardize the concept of “adequacy”. Methods: We performed a retrospective analysis of average-risk screening colonoscopy reports submitted to the Clinical Outcomes Research Initiative (CORI) data repository between 10/ 2009 and 8/2012. We included only reports documenting a BBPS score and a recommendation for timing of the next colonoscopy and excluded procedures with polyps. We evaluated recommended follow-up intervals stratified by total Figure 1. Total scores on part-task training box for each group of participants. Cystic duct stone.