title: Double flap technique for reconstruction of anterior skull base defects after craniofacial tumor resection: technical note.
abstract: BACKGROUND
  Successful reconstruction of large anterior skull base (ASB) defects after craniofacial resection of malignant skull base tumors is paramount for preventing cerebrospinal fluid (CSF) fistulas. The vascularized pedicled pericranial flap (PCF) has been the gold standard for repairing ASB defects after transbasal transcranial approaches. However, flap necrosis and delayed CSF leaks can occur after adjuvant radiation therapy. We describe a "double flap" reconstruction technique in which the PCF is augmented inferiorly by a secondary vascularized pedicled nasoseptal flap (NSF) that is harvested and rotated using an endoscopic endonasal approach.
  
  
  METHODS
  This technique is illustrated in 2 patients who underwent a combined cranionasal (transbasal and endoscopic endonasal) approach for large sinonasal malignancies with significant intracranial extension (1 esthesioneuroblastoma, 1 sinonasal teratocarcinosarcoma). After tumor removal via a combined cranionasal approach, primary repair of the ASB dural defect was performed with a free patch graft. The ASB defect was then repaired using the double flap technique with a vascularized PCF from above and augmented with a vascularized NSF from below.
  
  
  RESULTS
  Postoperatively, there were no complications of CSF leakage, meningitis, or tension pneumocephalus in both patients. After subsequent radiation therapy, the double flap repair remained intact at 2 years postoperatively in both patients.
  
  
  CONCLUSIONS
  The double flap skull base reconstruction technique provides an additional barrier of vascularized tissue to prevent CSF leakage, meningitis, tension pneumocephalus, and postradiation necrosis. This technique is a viable option if a combined transcranial and transnasal endoscopic tumor resection is performed and postoperative radiation is anticipated.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, NJ 07103, USA. jean.anderson.eloy@gmail.com
authors.forename: Jean Anderson
authors.initials: JA
authors.lastname: Eloy
authors.forename: Osamah J
authors.initials: OJ
authors.lastname: Choudhry
authors.forename: Lana D
authors.initials: LD
authors.lastname: Christiano
authors.forename: Dare V
authors.initials: DV
authors.lastname: Ajibade
authors.forename: James K
authors.initials: JK
authors.lastname: Liu
mesh_terms: D065634:Cerebrospinal Fluid Leak; D002559:Cerebrospinal Fluid Rhinorrhea / Q000209:etiology / Q000601:surgery; D018304:Esthesioneuroblastoma, Olfactory / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000601:surgery*; D019651:Plastic Surgery Procedures / Q000379:methods*; D019292:Skull Base Neoplasms / Q000601:surgery*; D013524:Surgical Flaps; D018243:Teratocarcinoma / Q000601:surgery*