title: Endoscopic ultrasound-guided placement of plastic vs. biflanged metal stents for therapy of walled-off necrosis: a retrospective single-center series.
abstract: OBJECTIVE
  Recently, a novel fully covered and biflanged metal stent (BFMS)dedicated to the drainage of walled-off necrosis(WON) was developed. The aim of this study was to retrospectively evaluate the safety, efficacy, and cost performance of drainage of WON using the novel BFMS compared with a traditional plastic stent.
  
  
  METHODS
  A total of 70 patients with symptomatic WON were treated under endoscopic ultrasound (EUS) guidance. Initial drainage was conducted using the single gateway technique with placement of one or more plastic stents or a single BFMS.If drainage was unsuccessful,direct endoscopic necrosectomy (DEN)was performed.
  
  
  RESULTS
  There were no statistically significant differences in rates of technical success, clinical success,and adverse events between plastics stents and BFMS, despite the size of WON in the BFMS group being significantly larger than that in the plastic stent group (105.6 vs. 77.1 mm; P=0.003).The mean procedure times for the first EUS-guided drainage and for re-intervention were significantly shorter in the BFMS group than in the plastic stent group (28.8±7.1 vs. 42.6±14.2, respectively,for drainage, P<0.001; and 34.9±8.5 vs.41.8±7.6, respectively, for re-intervention, P<0.001). There was no statistically significant difference in the total cost between plastic stent and BFMS use in the treatment of WON ($5352vs. $6274; P=0.25).
  
  
  CONCLUSIONS
  Plastic stents and BFMS were safe and effective for the treatment of WON. In particular,BFMS placement appeared to be preferable for initial EUS-guided drainage and additional reintervention(e.g. DEN) as it reduced the procedure time. Prospective randomized controlled trials are warranted.
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Mukai
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Itoi
authors.affiliation: University of North Carolina, Chapel Hill, North Carolina, United States.
authors.forename: Todd H
authors.initials: TH
authors.lastname: Baron
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sofuni
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Fumihide
authors.initials: F
authors.lastname: Itokawa
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Kurihara
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Tsuchiya
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ishii
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Shujiro
authors.initials: S
authors.lastname: Tsuji
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Ikeuchi
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Reina
authors.initials: R
authors.lastname: Tanaka
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Umeda
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Tonozuka
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Honjo
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Gotoda
authors.affiliation: Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
authors.forename: Fuminori
authors.initials: F
authors.lastname: Moriyasu
authors.affiliation: First Department of Internal Medicine, Gifu University Hospital, Gifu, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yasuda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003362:Cost-Benefit Analysis; D004322:Drainage / Q000191:economics / Q000295:instrumentation* / Q000379:methods; D019160:Endosonography; D005260:Female; D017721:Hospital Costs; D006801:Humans; D007564:Japan; D008297:Male; D008670:Metals / Q000191:economics; D008875:Middle Aged; D019283:Pancreatitis, Acute Necrotizing / Q000000981:diagnostic imaging / Q000191:economics / Q000628:therapy*; D010969:Plastics / Q000191:economics; D012189:Retrospective Studies; D015607:Stents / Q000191:economics; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D008670:Metals; D010969:Plastics