Single-step EUS-guided transmural drainage of simple and complicated pancreatic pseudocysts

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1 ORIGINAL ARTICLE Single-step EUS-guie transmural rainage of simple an complicate pancreatic pseuocysts Mainor R. Antillon, MD, Raj J. Shah, MD, Gregory Stiegmann, MD, Yang K. Chen, MD Denver, Colorao, USA Backgroun: Single-step EUS-guie transmural rainage of pseuocysts has been reporte, but there are no publishe prospective stuies on clinical outcomes. Objective: To assess the safety an the efficacy of single-step EUS-guie placement of large enoprostheses to treat simple an complicate pseuocysts. Design: Prospective cohort stuy. Setting: Single tertiary referral center. Patients: Consecutive patients referre for management of symptomatic chronic pancreatic pseuocysts O4 cm in size. Interventions: Single-step EUS-guie transmural pseuocyst rainage performe with a linear-array echoenoscope for placement of 10F stents in aults an 7F stents in chilren. Main Outcome Measures: Complete or partial (O50% reuction) resolution of pseuocyst on follow-up imaging, recurrence, clinical response, an proceure-relate complications. Recurrence was efine as the reappearance of a pancreatic pseuocyst in the same location. Results: There were 33 patients, with a mean age of 43 years. Meian pseuocyst size was 8.5 cm (range, 4-20 cm). Fourteen patients (42%) ha infecte pseuocysts, 8 patients (24%) ha gastric varices, an 16 patients (48%) ha no visible enoscopic bulge. Stent placement was successful in 31 patients (94%). Twenty-seven patients (82%) ha complete resolution of a pseuocyst; 4 patients (12%) ha partial resolution, with symptom relief. There were 2 major complications an 3 minor complications. Recurrence of a pseuocyst was observe in only 1 patient over a meian follow-up of 46 weeks. Limitations: No ranomize treatment arm comparing this technique with conventional enoscopic rainage. Conclusions: Single-step EUS-guie transmural rainage with large enoprostheses is a safe an effective therapy for patients with simple an complicate pancreatic pseuocysts. (Gastrointest Enosc 2006;63: ) Enoscopic rainage of symptomatic pancreatic pseuocysts is a proven treatment an can be performe via a transpapillary an/or transmural approach. 1,2 There is general agreement that optimal rainage of large pseuocysts is best accomplishe by placing multiple large-caliber stents. The conventional technique uses a uoenoscope with fluoroscopic guiance, an gastric varices or nonbulging pseuocysts are usually consiere contrainications for transmural rainage. Copyright ª 2006 by the American Society for Gastrointestinal Enoscopy /$32.00 oi: /j.gie With the introuction of EUS, EUS-assiste rainage has been avocate for ae safety, by allowing proper selection of an optimal site for the neele puncture, thus avoiing major vessels an ajacent structures. However, this technique requires a sequential approach. 3 Initially, an echoenoscope is use to evaluate the pseuocyst an surrouning structures an to ientify the best site for rainage. Then a uoenoscope with a 4.2-mm operating channel is use with fluoroscopic guiance for placement of large enoprostheses. This sequential approach likely increases proceure time as well as cost. Furthermore, when switching from echoenoscope to uoenoscope, the best angle of puncture cannot be assure. Real-time EUS monitoring of the Volume 63, No. 6 : 2006 GASTROINTESTINAL ENDOSCOPY 797

2 EUS-guie pseuocyst rainage Antillon et al puncture site an the neele angle is particularly important in patients with known or suspecte gastric or uoenal varices, an rainage of nonbulging pseuocysts can be performe with greater confience. More recently, single-step EUS-guie pseuocyst rainage has been escribe. 4,5 The small operating channel (2.8 mm) of first-generation curve linear-array (CLA) echoenoscopes initially limite stent options to 8.5F iameter or less. 6 One small case series escribe EUSguie placement of a 6F nasobiliary catheter for rainage of pseuocysts in 6 patients with portal hypertension an intervening vessels. 7 With the availability of CLA echoenoscopes with a larger (3.7 mm) operating channel, placement of large (10F) enoprostheses now is feasible. Two single case reports escribe the placement of a single 10F stent into a pseuocyst 8,9 ; however, there are no reports of placement of more than one 10F stent uring a single EUS proceure. The purpose of this prospective stuy was to evaluate the safety an the efficacy of performing single-step EUS-guie rainage in consecutive patients referre for treatment of a symptomatic pancreatic pseuocyst. PATIENTS AND METHODS The stuy was approve by the Colorao Multi-Institutional Review Boar. All patients gave informe consent. During the stuy perio, beginning on December 1, 2001, 34 consecutive patients presente to the University of Colorao Hospital for treatment of symptomatic pancreatic pseuocysts at least 4 cm in size an more than 8 weeks ol. One patient unerwent surgical rainage without being consiere for enoscopic rainage; the remaining 33 patients with chronic pseuocysts were enrolle in this stuy. Before the proceure, all patients were evaluate, an prior imaging stuies were reviewe. All patients receive a single ose of intravenous prophylactic antibiotics (500 mg levofloxacin intravenous piggyback) followe by 5 to 7 ays of oral antibiotics after the rainage proceure. Pancreatography was not routinely performe an was one only at the iscretion of the enoscopist. EUS-guie transmural rainage of the pseuocysts (enoscopic cystgastrostomy or cystuoenostomy) was performe by using a single-step technique in the following manner: 1. EUS an enoscopic inspection of the pseuocyst(s), the gastric an uoenal walls, an the surrouning organs an structures was performe by using a large-channel CLA echoenoscope (Aloka GF-UCT140- AL5 [3.7-mm operating channel, 12.6-mm insertion tube]; Olympus America Corp, Melville, NY). A smaller echoenoscope (Aloka GF-UC140P-AL5 [2.8-mm operating channel, 11.8-mm insertion tube]; Olympus) was use for younger peiatric patients with a small boy Capsule Summary What is alreay known on this topic Conventional enoscopic rainage of pancreatic pseuocysts is generally performe only in selecte patients who have bulging an uncomplicate pseuocysts. CLA echoenoscopes with a larger (3.7 mm) operating channel allow placement of large (10F) enoprostheses. What this stuy as to our knowlege In a prospective stuy of 33 consecutive patients, single-step, EUS-guie, transmural rainage of symptomatic pancreatic pseuocysts with large enoprostheses was safe an effective in patients with both simple an complicate pseuocysts. The EUS-guie approach allows enoscopic rainage in patients with nonbulging pseuocysts or gastric funal varices. size. The best site for rainage was then ientifie by using only EUS guiance (usually the most epenent portion of the pseuocyst that can be safely accesse, regarless of location of enoscopically visible bulge, if present) an a 19-gauge neele (Echotip Ultra Enoscopic Ultrasoun Neele; Cook Enoscopy, Winston- Salem, NC) was use to puncture the wall uner real-time EUS guiance to gain access to the cavity (Fig. 1). The stylet was remove, an a cyst flui sample was submitte for analysis, if appropriate. 2. With simultaneous EUS an fluoroscopic guiance, a inch guiewire with a 5-cm hyrophilic tip was avance through the neele into the pseuocyst, creating a generous loop of wire insie the cavity. The neele was then remove, leaving the guiewire in place (Fig. 2). 3. The opening of the cystgastrostomy or the cystuoenostomy was create by using limite bursts of iathermy ERBE, Enocut at 200 W (ERBE USA, Marietta, Ga) with a RX neele-knife sphincterotome over the guiewire (Microvasive Enoscopy, Boston Scientific Corp, Natick, Mass). 4. The opening was enlarge by using a 6- to 10-mm wireguie Hurricane RX Balloon Dilator (Microvasive Enoscopy) (Figs. 3 an 4). 5. Placement of the first 10F, 2- or 3-cm ouble-pigtail stent (Cook Enoscopy) was performe over the wire, with simultaneous enoscopic an fluoroscopic guiance. 6. The inch wire was reinserte into the same opening by using the echoenoscope, followe by elivery of the secon 10F ouble-pigtail stent. (Figs. 5 an 6). Only one 10F stent was place if the cyst cavity was not large enough to accommoate 2 stents or if it was not possible to pass 2 stents. 798 GASTROINTESTINAL ENDOSCOPY Volume 63, No. 6 :

3 Antillon et al EUS-guie pseuocyst rainage Figure 1. EUS-guie puncture of a pancreatic pseuocyst with a 19- gauge fine neele introuce through the operating channel of a therapeutic CLA echoenoscope. Figure 3. Fluoroscopic view of balloon ilation to enlarge a gastric wall/ pseuocyst fistula previously create by wire-guie neele-knife cautery. Figure 4. Enoscopic view of the opening into the pseuocyst cavity after balloon ilation. Figure 2. Fluoroscopic view of the placement of a inch guiewire into the pseuocyst cavity. Pseuocyst infection was suspecte if the presence of hyperechoic material within the cyst occupie more than 50% of the cyst cavity. A iagnosis of infecte pseuocyst was mae if pus was note uring enoscopic rainage an/or if the cyst flui was positive for an infectious organism on cultures. All patients were reevaluate at 4 to 8 weeks by EUS, with or without interim CTs, for complete resolution of the pseuocyst, an stents were remove uring the same encounter if no resiual cyst was foun. Follow-up was performe by clinic visits, chart review, an telephone calls thereafter. RESULTS Characteristics of stuy patients an pseuocysts Thirty-three patients ha a total of 35 attempts at EUSguie transmural pseuocyst rainage; 1 patient require EUS-guie rainage of 2 pseuocysts, whereas another patient ha 2 faile attempts at EUS rainage. There were 15 men an 18 women, with a mean age of 42 years (range, 9-69 years); 2 patients were chilren ages 9 an 10 years. Etiology of pancreatitis were ethanol abuse (n Z 21), after ERCP (n Z 2), gallstone pancreatitis (n Z 2), trauma (n Z 1), unresectable pancreatic cancer (n Z 1), an iiopathic (n Z 6). The pseuocysts were locate in the pancreatic boy (n Z 27), hea (n Z 4), Volume 63, No. 6 : 2006 GASTROINTESTINAL ENDOSCOPY 799

4 EUS-guie pseuocyst rainage Antillon et al Figure 5. Enoscopic view of two 10F ouble-pigtail stents raining the pseuocyst. an tail (n Z 2). The meian size of pseuocysts was 8.5 cm (range, 4-20 cm). Twenty-three patients (70%) ha significant comorbi conitions. Seven patients ha chronic liver isease, incluing 3 with cirrhosis. Three patients ha splenic thrombosis seconary to pancreatitis. Other associate comorbiities were iabetes mellitus (n Z 4), hypertension (n Z 4), hypothyroiism (n Z 3), coronary artery isease (n Z 1), Crohn s isease (n Z 1), breast cancer (n Z 1), an pancreatic cancer (n Z 1). Eighteen of 33 patients (55%) ha a pancreatography either before or concurrent with the EUS-rainage proceure. Eight of these 18 patients (44%) ha raiographic evience of pancreatic-uct communication with the pseuocyst; the status of the remaining 15 patients was not known. The stomach was the best site for EUS-guie rainage in 28 patients (85%). Bulging of the cyst into the stomach was note enoscopically in 15 patients (54%). The uoenum was the best site for EUS-guie rainage in 5 patients (15%). Bulging of the cyst into the uoenum was foun in 2 of the 5 patients. Thus, EUS imaging was the sole guie to the cyst puncture site in 16 of the 33 patients (49%) in this series. Furthermore, 8 patients (24%) ha gastric varices, 3 (38%) of whom were etectable only by EUS; this fining was not consiere to be a contrainication for EUS-guie rainage. Technical outcomes of EUS rainage Transmural rainage was successfully establishe in 31/33 patients (94%, 29 aults an 2 chilren) but faile in 2 ault patients. Of the 29 aults with establishe rainage, 25 patients ha placement of two 10F ouble-pigtail stents through the same puncture site; 2 patients require only one 10F stent because of a smaller cyst size; 1 patient ha successful placement of one 10F stent by using the echoenoscope, but a secon 10F stent was elivere into the same opening by using a uoenoscope; 1 Figure 6. Fluoroscopic view of two 10F ouble-pigtail stents raining the pseuocyst. patient ha 2 successful cystgastrostomy proceures for separate pseuocysts, performe on ifferent ays. A smaller echoenoscope (Aloka GF-UC140P-AL5; Olympus) was use for the 2 peiatric patients in this series, because of their small boy size. One patient ha successful placement of two 7F ouble-pigtail stents through the same puncture site. The other patient ha large gastric varices an receive only one 7F stent before the proceure was terminate for bleeing at the puncture site that compromise enoscopic visibility; the latter require transfusion of 3 units of packe re bloo cells but no aitional intervention for control of bleeing was necessary. Only 3 of the 8 patients (38%) with proven communicating pseuocysts were treate with transpapillary stent placement (5F or 7F) in conjunction with EUS-guie transmural rainage. Transpapillary rainage was not attempte in any of the remaining 30 patients. In 2 patients, an 8.5F nasocystic tube was place into the pseuocyst alongsie the two 10F ouble-pigtail stents by using the echoenoscope uring the same session, for short-term irrigation of thick cystic flui (neither patient ha transpapillary stent placement). Complete resolution of the pseuocyst was achieve in 27 (82%) of the 33 patients at the inex proceure or in 87% of 31 patients who ha successful stent placement. Four aitional patients (12%) ha only partial resolution (O50% reuction in cyst size), accompanie by symptom resolution (1 peiatric patient an 3 ault patients). Enoscopic treatment was reattempte in only 1 patient after a faile initial proceure but was not reattempte in any of the patients who ha partial resolution. A total of 14 patients (42%) ha infecte pseuocysts. Eight of 14 (57%) ha pancreatic abscesses (evience of pus), an 6 others ha confirme infection by positive 800 GASTROINTESTINAL ENDOSCOPY Volume 63, No. 6 :

5 Antillon et al EUS-guie pseuocyst rainage microbiologic analysis of EUS-guie cyst-flui aspirates. All infecte pseuocysts were treate with a course of antibiotics. The presence of infection i not aversely affect the outcomes of pseuocyst rainage. Proceure-relate complications Two patients (6%) ha major complications from the proceure. Perforation, with a subphrenic abscess, occurre in 1 patient after EUS-guie cystuoenostomy. This patient require exploratory laparotomy, rainage of the abscess, an repair of the perforation 3 ays after a faile attempt at transmural rainage. The patient recovere uneventfully. One peiatric patient with large gastric funal varices ble at the gastric puncture site an require transfusion of 3 units of bloo; on follow-up CT, the single stent was note to have migrate into the partially obliterate cyst cavity, but no therapy was require. Minor proceure-relate complications occurre in 3 other patients (9%) an require hospitalization for observation (asymptomatic pneumoperitoneum, minor bleeing into the cyst, an minor bleeing at the puncture site). Thus, the overall proceure-relate complication rate was 5 of 33 patients (15%). There were no mortalities. Follow-up The meian follow-up was 46 weeks (interquartile range [IQR], weeks), an no patient was lost to follow-up uring the stuy perio. Stents were remove after a meian of 6 weeks (IQR, 5-9 weeks). Symptoms thought to be relate to the pseuocyst completely resolve after EUS rainage in 26 of the 33 patients (79%), incluing 4 patients who ha only partial resolution (O50% reuction in size) of the pseuocysts. Of the 27 patients with complete resolution on follow-up imaging, 22 (82%) became asymptomatic; the other 5 patients continue to have pain espite complete resolution, presumably because of unerlying chronic pancreatitis. Of the 4 patients who ha only partial resolution of the pseuocyst, all remaine asymptomatic; 3 ha no further tests or interventions uring follow-up; the fourth patient ha 2 follow-up CTs, uring a 10-month perio, that showe no change in size. One patient who ha a previously faile surgical rainage ha only partial resolution after EUS rainage; this patient subsequently unerwent a successful percutaneous rainage. Two patients ha surgery uring the follow-up perio: 1 patient who ha EUS-guie rainage of an infecte pseuocyst subsequently require surgical ebriement of infecte pancreatic necrosis; the other ha surgical rainage of a e novo infecte pseuocyst not previously treate enoscopically. At a meian follow-up of 46 weeks, only 1 patient (4%) of 27 who ha complete resolution after EUS-guie transmural rainage evelope a recurrence of the pseuocyst. Three weeks after stent removal (7 weeks after EUS rainage), this patient was hospitalize at another facility for severe abominal pain; a pseuocyst (presumably at the same location) was foun, an this was raine percutaneously, with eventual complete resolution, although the pain has remaine unchange. DISCUSSION This is the largest prospective stuy that evaluate the feasibility, safety, an efficacy of single-step EUS-guie transmural pseuocyst rainage in a cohort of consecutive patients referre for treatment of symptomatic pancreatic pseuocysts. We report the success an recurrence rates over a meian follow-up of 46 weeks, as well as the proceure-relate complications of EUS-guie elivery of large-caliber enoprosthesis (10F) by using only 1 enoscope at a single session. During the stuy perio, only 1 patient was inavertently exclue from our series; this patient was amitte to our Surgical Service for surgical rainage without being consiere for enoscopic treatment. This consecutive series inclue a large proportion (more than half) of cases that normally woul be consiere contrainicate or more ifficult to treat by using the conventional approach: infecte pseuocysts (42%), nonbulging pseuocysts (48%), an gastric varices (24%). Two large (10F) enoprosthesis were elivere via a transgastric or transuoenal approach, except in chilren who were treate by using a smaller-iameter echoenoscope (2.8-mm operating channel) an two 7F stents. In this prospective stuy, the proceure was technically successful in 94% of all patients. By intention-to-treat analysis, complete resolution of pseuocysts was achieve in 82% of all patients or in 87% of 31 patients who were successfully stente. Eighty-five percent ha a transgastric rainage, whereas the remainer ha transuoenal rainage. With the exception of 2 major complications, the overall morbiity was low. These results compare very favorably with conventional enoscopic rainage. 10,11 Howell et al 12 reviewe the publishe literature through 1998 an foun that, among 141 patients with pseuocysts treate enoscopically, transmural rainage as the only metho of rainage achieve initial complete resolution in only 26 of 37 patients (70%), with a morbiity of 19% an a recurrence rate of 16% after a variable uration of follow-up. In this review, the transuoenal approach was foun to be more effective (80%-100%) than the transgastric approach (30%) 12 whereas, we foun that both transgastric an transuoenal rainage equally ha excellent outcomes when using the EUS-guie approach. Despite the fact that EUS-guie rainage was largely establishe via a transgastric approach (85%) in this stuy, complete resolution was achieve in 82%, an the recurrence rate was only 4% at a meian follow-up of 46 weeks. A major limitation of conventional enoscopic rainage is the requirement for an enoscopically visible bulge in the wall of the stomach or the uoenum. One single-center Volume 63, No. 6 : 2006 GASTROINTESTINAL ENDOSCOPY 801

6 EUS-guie pseuocyst rainage Antillon et al stuy reporte a 42% incience of nonbulging pseuocysts over a 2-year perio 13 ; this is similar to our experience where 48% of patients presente with a nonbulging pseuocyst. Aitionally, 8 patients (24%) in our series ha evience of gastric varices, 5 of whom also ha a nonbulging pseuocyst. Thus, 19 of 33 patients (58%) in our stuy cohort woul have been consiere inappropriate caniates for conventional enoscopic rainage. Given the fact that conventional enoscopic rainage is generally performe only in highly selecte patients with bulging an uncomplicate pseuocysts, the overall success rates observe in this cohort of unselecte patients when using the EUSguie approach is clearly superior. Until recently, EUS-guie transmural rainage of pseuocysts was limite by the inability to place large-caliber stents at the initial proceure. 4-6 Sanchez Cortes et al 13 escribe 33 patients in whom a small-caliber (6.5F) stent or nasocystic rain was place with EUS guiance. However, a secon proceure was require several ays later to upsize to larger (10F) stents by using a uoenoscope with a 4.2-mm operating channel. 13 Thus, this was really a sequential approach, requiring 2 separate proceures with 2 ifferent enoscopes. By using this 2-step approach, their technical success rate approximate our success rates when using a single-step, EUS-guie technique. Combine transmural an transpapillary rainage in patients with a communicating pseuocyst has been avocate by some, with reporte success rates in the range of 70% to 100%. 12 However, superiority of the combine approach over transmural rainage alone has not been establishe in a prospective, ranomize stuy. Because we i not routinely perform ERCP before EUS-guie rainage, the prevalence of communicating pseuocysts in our cohort is unknown. However, at ERCP, uctal communication has been reporte in anywhere from 23% to 66% of patients who present for pseuocyst rainage. 11 In our stuy, EUS-guie transmural rainage was the only technique use in all but 3 patients. One patient ha concurrent transpapillary placement of a 7F stent into the cyst. A secon patient ha concurrent transpapillary placement of a 5F stent into the pancreatic uct that traverse the communicating fistula. The thir patient ha persistent pancreatic ascites an pleural effusion, espite complete resolution of the pseuocyst after transmural rainage. At ERCP, a complete ownstream obstruction of the main pancreatic uct coul not be traverse by using the transpapillary approach; the ascites an effusions subsequently resolve after upstream placement of two 5F stents via EUS-guie pancreaticogastrostomy. We conclue that excellent overall outcomes can be achieve by using EUS-guie transmural rainage alone, without having to routinely obtain a pancreatogram to ientify uctal communication an to perform transpapillary rainage. Nasocystic irrigation of infecte pseuocysts (42% of the cohort) also appears to be unnecessary, particularly when EUS-guie rainage can be establishe with 2 large-bore stents. At a meian follow-up of 46 weeks, only 1 (4%) of 27 patients who ha initial complete resolution evelope a pseuocyst recurrence. In contrast, up to 16% of recurrences has been observe after conventional enoscopic rainage. 12 Without a ranomize comparison, it is not clear if the low recurrence rate an excellent overall outcome is attributable solely to our EUS technique (ie, selecting the most epenent an appropriate rainage site by using EUS guiance alone), or to the use of ual large-caliber stents, or to both. Similarly, espite the inclusion of patients with gastric varices an nonbulging pseuocysts, the overall morbiity was only 13% after EUS rainage, which compares favorably with the reporte morbiity after conventional transmural rainage. 12 In summary, single-step EUS-guie transmural rainage with placement of 1 or more large enoprostheses is a very safe an effective therapy for symptomatic pancreatic pseuocysts. The EUS-guie approach substantially extens the reach of enoscopic rainage to inclue patients with nonbulging pseuocysts an gastric funal varices, an pseuocyst infection oes not appear to aversely impact the outcome. Ranomize stuies are neee to irectly compare the safety an efficacy of EUS-guie rainage with conventional enoscopic rainage. DISCLOSURE Y. K. Chen has receive research grants, unrestricte eucational grants, an honorarium from Olympus America Corp. REFERENCES 1. Binmoeller KF, Seifert H, Walter A, et al. Transpapillary an transmural rainage of pancreatic pseuocysts. Gastrointest Enosc 1995;42: Cremer M, Deviere J, Engelholm L. Enoscopic management of cysts an pseuocysts in chronic pancreatitis: long term follow-up after 7 years of experience. Gastrointest Enosc 1989;35: Vosoghi M, Sial S, Garrett B, et al. EUS-guie pancreatic pseuocyst rainage: review an experience at Harbor-UCLA Meical Center. MeGenMe 2002;4. Available at: viewarticle/ Giovannini M, Bernarini D, Seitz JF. Cystogastrotomy entirely performe uner enosonography guiance for pancreatic pseuocyst: results in six patients. Gastrointest Enosc 1998;48: Vilmann P, Hancke S, Pless T, et al. One-step enosonography-guie rainage of a pancreatic pseuocyst: a new technique of stent elivery through the echo enoscope. Enoscopy 1998;30: Wiersema MJ. Enosonography-guie cystouoenostomy with a therapeutic ultrasoun enoscope. Gastrointest Enosc 1996;44: Sriram PVJ, Kaffes AJ, Rao GV, et al. EUS-guie rainage of pancreatic pseuocysts complicate by portal hypertension or by intervening vessels. Enoscopy 2005;37: Palazzo L, Ponsot P, O Toole D. Cystgastrostomy with 10 French stent performe uner enosonography guiance for pancreatic pseuo cyst [abstract]. Gastrointest Enosc 2000;51:AB Wiersema MJ, Baron TH, Chari ST. Enosonography-guie pseuocyst rainage with a new large-channel linear scanning echoenoscope. Gastrointest Enosc 2001;53: GASTROINTESTINAL ENDOSCOPY Volume 63, No. 6 :

7 Antillon et al EUS-guie pseuocyst rainage 10. Kozarek RA, Brayko CM, Harlan J, et al. Enoscopic rainage of pancreatic pseuocysts. Gastrointest Enosc 1985;31: Smits ME, Rauws EA, Tytgat GN, et al. The efficacy of enoscopic treatment of pancreatic pseuocysts. Gastrointest Enosc 1995;42: Howell DA, Elton E, Parsons WG. Enoscopic management of pseuocysts of the pancreas. Gastrointest Enosc Clin N Am 1998;8: Sanchez Cortes E, Maalak A, Le Moine O, et al. Enoscopic cystenterostomy of nonbulging pancreatic flui collections. Gastrointest Enosc 2002;56: Receive June 19, Accepte October 13, Current affiliations: Division of Gastroenterology an Hepatology (Drs Antillon, Shah, Chen); an Department of Surgery (Dr Stiegmann), University of Colorao Health Sciences Center, Denver, Colorao, USA. Presente in part at Digestive Disease Week, Orlano, Floria, May 17-22, Reprint requests: Yang K. Chen, MD, University of Colorao Hospital, Anschutz Centers for Avance Meicine, 1635 N. Ursula St, Rm OP 6710, Aurora, CO Volume 63, No. 6 : 2006 GASTROINTESTINAL ENDOSCOPY 803