title: Transluminal retroperitoneal endoscopic necrosectomy with the use of hydrogen peroxide and without external irrigation: a novel approach for the treatment of walled-off pancreatic necrosis.
abstract: BACKGROUND
  Transluminal retroperitoneal endoscopic necrosectomy (TREN) is an attractive NOTES technique alternative to surgery for treatment of walled-off pancreatic necrosis (WOPN). The main limitations to this technique are the need for repeated sessions, prolonged external irrigation, and EUS availability. In our study, we introduced new modifications, including the use of hydrogen peroxide, and abandoning the use of EUS and external irrigation.
  
  
  METHODS
  This is a retrospective study of outcome of consecutive patients who underwent TREN for WOPN between April 2011 and August 2012. The technique included (1) non-EUS-guided transluminal drainage, and (2) direct endoscopic debridement using hydrogen peroxide and different accessories. No external irrigation was used.
  
  
  RESULTS
  Ten patients were included. Initial clinical and technical success was achieved in all patients. Complete radiological success and long-term clinical efficacy was achieved in nine patients (1 patient had an inaccessible left paracolic gutter collection and died 62 days after endotherapy). Mean number of sessions was 1.4 (range 1-2). Complications included bleeding, which was self-limited in three patients and endoscopically controlled in one. All patients avoided surgery, and no recurrence was reported during median follow-up of 289 (range 133-429) days.
  
  
  CONCLUSIONS
  TREN is a safe and effective treatment for WOPN and could be performed safely without EUS guidance in selected cases. Hydrogen peroxide played a major role in reduction of number of sessions and timing. External irrigation of WOPN is not necessary, if adequate debridement could be achieved.
authors.affiliation: Gastrointestinal Endoscopy Unit, Faculty of Medicine, Kasr Alainy Hospital, Cairo University, Cairo, Egypt, dr_mhafez@hotmail.com.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abdelhafez
authors.forename: Mayada
authors.initials: M
authors.lastname: Elnegouly
authors.forename: M S
authors.initials: MS
authors.lastname: Hasab Allah
authors.forename: Mostafa
authors.initials: M
authors.lastname: Elshazli
authors.forename: Hany M S
authors.initials: HM
authors.lastname: Mikhail
authors.forename: Ayman
authors.initials: A
authors.lastname: Yosry
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016063:Blood Loss, Surgical; D002760:Cholangiopancreatography, Endoscopic Retrograde; D003646:Debridement / Q000379:methods*; D004106:Dilatation; D004322:Drainage / Q000379:methods; D004564:Electrocoagulation; D005260:Female; D005471:Fluoroscopy; D005500:Follow-Up Studies; D005839:Gentamicins / Q000627:therapeutic use; D006488:Hemostasis, Surgical; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D009336:Necrosis; D019283:Pancreatitis, Acute Necrotizing / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D010533:Peritoneal Lavage / Q000706:statistics & numerical data; D015641:Radiography, Interventional; D012187:Retroperitoneal Space; D012189:Retrospective Studies; D012965:Sodium Chloride; D015607:Stents; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D019564:Unnecessary Procedures
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D012965:Sodium Chloride; D006861:Hydrogen Peroxide