title: A systematic review of nonabsorbable, absorbable, and steroid-impregnated spacers following endoscopic sinus surgery.
abstract: BACKGROUND
  Middle meatal (MM) spacers may reduce adhesions following endoscopic sinus surgery (ESS). However, there is no consensus as to which materials and adjuncts are the most effective for this purpose. The primary objective of this study was to examine the effectiveness of absorbable spacers (AS) vs nonabsorbable spacers (NAS) in reducing adhesions following ESS for chronic sinusitis. Secondarily, we assessed steroidal vs nonsteroidal MM spacers in reducing adhesions.
  
  
  METHODS
  Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review of randomized controlled trials (RCTs) was conducted and a meta-analysis on relevant outcome data was performed. Electronic search was done using OVID MEDLINE, EMBASE, Cochrane Central register of Controlled Trials, and Web of Science. Independent data extraction and evaluation was conducted.
  
  
  RESULTS
  For our primary objective, 6 RCTs were included in the systematic review. A pooled estimate of relevant trials revealed a nonsignificant trend favoring AS in reducing adhesion formation compared to NAS (Relative Risk (RR), 0.40; 95% confidence interval [CI], 0.15-1.03). This trend was not apparent if NAS are left for greater than 48 hours after ESS. For our secondary objective, we identified 5 RCTs that compared steroidal vs nonsteroidal spacers. Although a pooled analysis could not be achieved due to inconsistent reporting of MM adhesions, 2 studies demonstrated significantly less adhesions in the steroidal spacer group.
  
  
  CONCLUSIONS
  Comparison between NAS and AS showed that there was no significant difference in adhesion rates if NAS are used for at least 48 hours after surgery. Steroidal spacers may reduce adhesions, but more consistent data reporting is required for meta-analysis.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Toronto, Ontario, Canada.
authors.forename: Xiao
authors.initials: X
authors.lastname: Zhao
authors.forename: Aman
authors.initials: A
authors.lastname: Grewal
authors.forename: Matthias
authors.initials: M
authors.lastname: Briel
authors.forename: John M
authors.initials: JM
authors.lastname: Lee
mesh_terms: D002908:Chronic Disease; D004724:Endoscopy; D006801:Humans; D059747:Nasal Surgical Procedures / Q000379:methods*; D010256:Paranasal Sinuses / Q000601:surgery*; D011183:Postoperative Complications / Q000517:prevention & control*; D016032:Randomized Controlled Trials as Topic; D012852:Sinusitis / Q000601:surgery*; D013256:Steroids / Q000008:administration & dosage; D013525:Surgical Instruments; D000267:Tissue Adhesions / Q000517:prevention & control; D016896:Treatment Outcome
chemical_list: D013256:Steroids
keywords: absorbable spacer; endoscopic sinus surgery; nonabsorbable spacer; steroid spacer; systematic review