Relaxing Sphenoidal Slit Incision to Extend the Anterior and Posterior Reach of Pedicled Nasoseptal Flaps During Endoscopic Skull Base Reconstruction of Transcribriform Defects: Technical Note and Results in 20 Patients

• Published in: World neurosurgery 2018-05, Vol.113, p.49-57
• Main Authors: Liu, James K., Mendelson, Zachary S., Kohli, Gurkirat, Eloy, Jean Anderson
• Format: Article
• Language: English
• Subjects: Cerebrospinal fluid leak; Endoscopic endonasal approach; Endoscopic skull base surgery; Pedicled nasoseptal flap; Relaxing slit incision; Skull base reconstruction; Transcribriform defect
• ISSN: 1878-8750; 1878-8769
• DOI: 10.1016/j.wneu.2018.01.142

Reconstruction of large anterior skull base (ASB) defects after an endoscopic endonasal transcribriform approach (EEA-TC) remains a challenge despite the advent of the vascularized pedicled nasoseptal flap (PNSF). We describe a relaxing PNSF slit incision that extends the anterior and posterior reach of the PNSF to maximize tensionless flap coverage of transcribriform ASB defects. A retrospective chart review was conducted on 20 consecutive patients who underwent endoscopic endonasal transcribriform approach and subsequent PNSF reconstruction with a relaxing slit incision. At the time of endoscopic ASB reconstruction, the PNSF is rotated into position so that the anterior margin of the flap is situated at the posterior table of the frontal sinus. A relaxing slit incision is made across the sphenoidal segment of the PNSF, which is the segment of flap that bridges across the sphenoid sinus once the flap is rotated into position. The anterior reach of the flap is increased to adequately cover the posterior table of the frontal sinus, and the redundant sphenoidal flap is rotated posteriorly to make contact to the bony planum sphenoidale. No patients developed postoperative cerebrospinal fluid leaks (0%). The ASB repair was monitored via postoperative outpatient nasal endoscopy at various time points, which demonstrated excellent mucosalization of the ASB with a mean follow-up of 19.2 months (range: 4.1–36.2 months). Our simple relaxing slit incision in the sphenoidal portion of the PNSF allows for maximal tensionless coverage of extensive transcribriform defects by increasing the anterior and posterior reach of the flap. •Large transcribriform defects are challenging to repair endoscopically even with a PNSF.•We report a technique to extend the reach of the PNSF for endoscopic skull base reconstruction.•A relaxing sphenoidal slit incision is made to extend the anterior and posterior reach.•This maximizes tensionless coverage of large transcribriform defects to prevent CSF leak.•The results are reported in 20 consecutive patients.