The Composite Mucosal Cartilaginous Septal Flap for Endoscopic Skull Base Reconstruction

Introduction: The nasoseptal flap has revolutionized endoscopic skull base surgery; however, adequate closure of large dural defects remains technically challenging. The use of a rigid component to form a gasket-seal around the bony defect margin may prove useful in reducing the rate of CSF fistula. Here we describe a modification of the nasoseptal flap, which allows the harvest of cartilage with its blood supply along with mucosa for a stronger repair of large skull base defects.

Methods: The technical feasibility of the composite mucosal cartilaginous septal flap was initially verified in a cadaveric head. The flap was elevated via a left Killian incision and a transcartilaginous incision 1.5 cm from the caudal margin of the septal cartilage. A bony cartilaginous cut was performed to complete the flap elevation on the left side of the septal bone. Following anterior skull base preparation, a 2-×-3-cm osteotomy was performed and repaired with two layers of fascia, the composite septal flap, and DuraSeal. Once reconstructed, a craniotomy was performed to evaluate the quality of the reconstruction with respect to water tightness, as well as resistance to displacement. This technique was then successfully applied in a live patient.

Results: The composite mucosal cartilaginous septal flap was successfully performed in a cadaver and a live patient. No adverse event was noted in the patient postoperatively.

Conclusion: This report confirms the feasibility of the above-described modification of the nasoseptal flap. It provides rigid cartilage, which retains its perichondrial attachment and blood supply, for use in a gasket-seal reconstruction of large skull base defects.