title: Layered sellar reconstruction with avascular free grafts: Acceptable alternative to the nasoseptal flap for repair of low-volume intraoperative cerebrospinal fluid leak.
abstract: BACKGROUND
  Although the nasoseptal flap has become the method of choice for reconstruction of intraoperative cerebrospinal fluid (CSF) leak in endoscopic minimally invasive surgery of the skull base, layered avascular graft techniques, including allografts and middle turbinate mucosal autografts, may provide comparable reconstructive success with decreased nasal morbidity.
  
  
  OBJECTIVE
  To describe a method of reconstruction of intraoperative CSF leak in endoscopic surgery of the sella turcica and analyze its postoperative success rate and associated comorbidities.
  
  
  METHODS
  A retrospective review of expanded endonasal sellar tumor resections from 2008-2014 was performed, and cases of layered intraoperative skull base reconstruction with avascular free grafts were identified. Demographic factors and comorbidities that predisposed to reconstruction failure (obstructive sleep apnea, obesity) were determined. Reconstruction-related nasal complications were also identified. Postoperative CSF leak rate was determined, and statistical analysis was performed to identify predictive factors for reconstructive failure.
  
  
  RESULTS
  Seventy-three cases were identified. Layered closure with avascular free grafts was performed. There were five cases of postoperative CSF leak (6.85%). The mean follow-up was 19 months (range, 1-76 months). Intraoperative high-flow CSF leak was a significant predictor of reconstruction failure on univariate (odds ratio 22 [95% confidence interval, 2.26-214]; p = 0.008) and multivariate analysis (odds ratio 33.6 [95% confidence interval, 2.30-492]; p = 0.010). There were no significant differences in postoperative leak rates among bony overlay graft types. There were five patients (7.9%) who experienced persistent crusting after surgery. There were no significant differences in crusting rates between allografts and mucosal grafts. There were no postoperative mucoceles.
  
  
  CONCLUSIONS
  In cases of low-volume intraoperative CSF leak, layered skull base repair with avascular free grafts was an acceptable alternative to the nasoseptal flap, which may reduce prolonged sinonasal healing and donor-site morbidities.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Roxbury
authors.forename: Tiffany
authors.initials: T
authors.lastname: Saavedra
authors.forename: Murugappan
authors.initials: M
authors.lastname: Ramanathan
authors.forename: Michael
authors.initials: M
authors.lastname: Lim
authors.forename: Masaru
authors.initials: M
authors.lastname: Ishii
authors.forename: Gary L
authors.initials: GL
authors.lastname: Gallia
authors.forename: Douglas D
authors.initials: DD
authors.lastname: Reh
mesh_terms: D065634:Cerebrospinal Fluid Leak / Q000209:etiology / Q000517:prevention & control*; D005500:Follow-Up Studies; D006801:Humans; D007431:Intraoperative Complications / Q000517:prevention & control*; D009300:Nasal Septum / Q000601:surgery*; D011379:Prognosis; D019651:Plastic Surgery Procedures; D012189:Retrospective Studies; D012658:Sella Turcica / Q000601:surgery*; D019291:Skull Base / Q000601:surgery*; D013524:Surgical Flaps / Q000706:statistics & numerical data*; D019737:Transplants; D017211:Treatment Failure; D016896:Treatment Outcome