7248USEFULNESS OF EXTRACORPOREAL SHOCK WAVELITHOTRIPSY FOR PANCREATOLITHIASIS.Ken Inoue, Jiro Ouchida, Takao Ohtsuka, Toshinaga Nabae, KazunoriYokohata, Hirokazu Noshiro, Masao Tanaka, Kyushu Univ, Graduate Schof Med Sci, Fukuoka, Japan.Aim Extracorporeal Shock Wave Lithotripsy(ESWL) is an effective treat-ment for gallstones and renal stones. However, few data are available onthe usefulness of ESWL for pancreatolithiasis. We evaluated the useful-ness of ESWL in the treatment of pancreatic stones. Patients and methods21 patients of pancreatolithiasis were analyzed. For these patients, we firstperform endoscopic sphincterotomy(EST) and attempt endoscopic removalof the stones. If complete clearance of the stones was not achieved by endo-scopic methods, ESWL was added. We evaluated the rate of therapeuticsuccess and complications after ESWL. Results Stone removal was suc-cessful by only EST in 9 patients(42%). In the remaining 12 patients,ESWL were employed. Among these 12 patients, complete stone removalwas achieved in all but one patients(93%). Symptomatic improvement wasobtained in all patients. Mortality was zero percent and mild acute pan-creatitis as a procedure related complication occurred in only one patient.Conclusions ESWL is a safe and effective treatment for the patients ofpancreatic stones. Combined with endoscopic therapy, ESWL may increasethe success rate of removal of the pancreatic stones.

7249CLINICAL USEFULNESS OF THE PANCREATIC STENT INPATIENTS WITH CHRONIC PANCREATITIS.Takeshi Ishihara, Taketo Yamaguchi, Toshio Tsuyuguchi, HiromitsuSaisho, Chiba Univ Sch of Medicine, Chiba, Japan.Background: Pancreatic stents are being used increasingly for the man-agement of symptomatic stricture of pancreatic duct in chronic pancreati-tis. But, temporary placement of pancreatic stent rarely results in strictureresolution. After removal of the stents, pain recurred in high frequency.Aim: To clarify how to maintain the effectiveness of pancreatic stent.Methods: The indication for pancreatic stent was to those patients who hadrecurrent episodes of pancreatitis and demonstrated dilatation of the mainpancreatic duct and a stricture distal to these changes. 36 patients withsymptomatic chronic pancreatitis (mean age: 46.8 years, 4 women, 32 men)were entered in this study. Pancreatic stents used in this study were plas-tic stent, which were originally manufactured for the purpose of biliarydrainage. The size of the stents were 7, 10 French in caliber. The patientswere divided into 4 groups; stent-unsuccess (14), stent-ineffective or aggra-vated the pancreatitis (3), stent-retrieved within 6 months regardless of itspatency (6), and stent-continued in situ and exchanged when the caliber ofdistal pancreatic duct were demonstrated ultrasonographically to beincreased and dilated again (16). In stent-continued cases, follow-up USwere practiced in every 4 weeks. Results: Success rate of pancreatic stentwas 22/36 (61.1%). Mean duration of effective pancreatic drainage perstent was 392 (2~1313) days. There were no significant difference between10 French plastic stent and 7 French plastic stent in the duration of effec-tive drainage. During a mean follow-up of 37.7 months, relapse of painwere experienced 12/14 (85.7%) in stent-unsuccess, 2/3 (66.7%) in stent-ineffective, 5/6 (83.3%) in stent-retrieved, and 0/16 (0%) in stent-continuedgroup. The complications of the stent were recognized in 4 cases (18.2%),dislocation of the stents in 3 cases (13.6%), cyst formation in 1 cases (4.5%).There were no serious complications in this study. Conclusion: For the pre-vention of relapse of pain, it is necessary to place the stent continuously.There appears to be a low risk of critical stent complications by periodicalfollow-up.

7250WHICH FACTORS PREDICT THE TIME REQUIRED FOR STONEREMOVAL AFTER ENDOSCOPIC BALLOON DILATION (EBD)AND SPHINCTEROTOMY (EST)? Jacques J. Bergman, Marco J. Bruno, Anne-Marie Berkel, Erik Aj Rauws,Paul Fockens, Guido Nj Tytgat, Kees Huibregtse, Acad Med Ctr,Amsterdam, Netherlands; Dept of Gastroenterology, Acad Med Ctr,Amsterdam, Netherlands.Aim: EBD is an alternative to EST in selected patients with bile ductstones. Since EBD does not enlarge the biliary orifice to the extent of EST,stone removal may be more difficult and more time consuming. We inves-tigated which factors predict the time required for endoscopic stoneremoval after EBD and EST. Methods: 202 consecutive patients with bile

duct stones of all sizes were randomized to EBD (8-mm dilation balloon)orEST after deep cannulation of the bile duct was achieved without preceed-ing precut*.In case stone removal failed after EBD an additional EST wasperformed. Mechanical lithotripsy was used when necessary. Stoneremoval time was defined as the time between randomization and end ofthe procedure. Results: 22 patients with a prior BII-gastrectomy wereexcluded from the analysis. See table for results. Multiple regression iden-tified stone diameter, stone number, and EBD as independent predictorsfor stone removal time. Conclusions: Stone removal after EBD is morelabour intensive than after EST and takes on average 10 minutes longer.The difference in stone removal time is most obvious for stone diametersbetween 10 and 15 mm where EBD requires mechanical lithotripsy in vir-tually all patients whereas this is not the case for EST. *Lancet 1997:349:1124-9.

Time required for stone removal after EDB and EST:a randomized trial

EST (n=87) EBD (n=93)

Median stone number (range) 1 (1-10) 1 (1-10)Median stone diameter (mm, range) 8 (3-27) 9 (3-37)Stone removal in one session 81 (93%) 82 (88%)Mechanical lithotripsy* 11 (13%)* 29 (31%)*Stone removal time (min, range), 20 (5-100)* 30 (10-110)*all patients*

diameter < 10 mm 15 2510 mm < diameter < 15 mm 15 38diameter > 15 mm 35 38

*p<0.005

7251NATURAL HISTORY OF ASYMPTOMATIC BILE DUCT STONESAT TIME OF CHOLECYSTECTOMY.Grant R. Caddy, John Kirby, Stephen J. Kirk, Allen Mike, John R.Moorehead, Tony C. Tham, Ulster Hosp, Dundonald, Belfast, UnitedKingdom.There is relatively little data on the natural history of asymptomatic bileduct stones. As there is currently uncertainty on the management ofasymptomatic bile duct stones at time of laparoscopic cholecystectomy, wefollowed up a group of patients over a 5-year period. METHODS: We fol-lowed up 59 patients who underwent laparoscopic cholecystectomy (studygroup). None of these patients had a pre-operative suspicion of bile ductstones and therefore no intra-operative cholangiogram or ERCP was per-formed pre or post surgery. Follow up was in the form of a telephone ques-tionnaire to their respective primary care physicians. The control grouphad no pre-operative suspicion of bile duct stones but had routine intra-operative cholangiogram performed. RESULTS: 59 patients were followedup for an average of 57 months (4.8 years)(range 30-78 months) afterlaparoscopic cholecystectomy. Mean age was 52yrs (range 31-84yrs). 4patients had seen their primary care physicians with symptoms of gastro-esophageal reflux disease. 2 patients were diagnosed with duodenitis fol-lowing EGD. 1 patient had been referred for barium enema for lowerabdominal pain and diagnosed with diverticulitis. 1 patient had ongoingnausea. 1 patient had continuing right upper quadrant pain, which wasdiagnosed as neuropathic pain, and referred to the pain clinic. None of thepatients had pancreatitis, jaundice, deranged liver function tests, ERCP orother biliary investigations. In the control group, intra-operative cholan-giogram was performed in 73 patients without suspected bile duct stones.4 of 73 (6%) patients had intraductal stones detected, which were removedeither endoscopically or, by surgery. CONCLUSIONS: The prevalence ofasymptomatic bile duct stones during time of cholecystectomy in our pop-ulation was 6% i.e. we would expect 3 patients in our study group to haveasymptomatic bile duct stones. We found that the study group had no com-plications related to bile duct stones during the 5-year follow up period.This would support the view that incidental bile duct stones found inpatients undergoing laparoscopic cholecystectomy do not need removed.

VOLUME 51, NO. 4, PART 2, 2000 GASTROINTESTINAL ENDOSCOPY AB305