Double Flap Technique for Reconstruction of Anterior Skull Base Defects after Craniofacial Tumor Resection

• Main Authors: Christiano, Lana D., Ajibade, Dare V., Eloy, Jean Anderson, Liu, James K.
• Format: Conference Proceeding
• Language: English
• ISSN: 1531-5010; 1532-0065
• DOI: 10.1055/s-2011-1274363

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 has been the gold standard for repair. However, flap necrosis and delayed CSF leaks can occur after adjuvant radiation therapy. We describe a double flap repair, where the pericranial flap is augmented inferiorly by a secondary vascularized nasoseptal flap (NSF) that is harvested and rotated using an endonasal endoscopic approach. This technique is illustrated in two patients who underwent resection of large sinonasal/anterior skull base malignancies with significant intracranial extension. Methods/Results: A 62-year-old man presented with headaches and confusion from a large sinonasal teratocarcinosarcoma that extended intracranially into the left frontal lobe with brain invasion and edema. The tumor was removed via a combined bifrontal transbasal and endonasal endoscopic approach. After primary repair of the dural defect with a free patch graft, the ASB defect was repaired with a vascularized pericranial flap from above and augmented with an NSF from below. Postoperatively, the patient was neurologically intact without evidence of CSF leakage, meningitis, or tension pneumocephalus. After subsequent radiation therapy, the double flap repair remained intact at 3, 6, and 9 months postoperatively. A 51-year-old woman presented with right-sided epistaxis and proptosis secondary to a large olfactory neuroblastoma that extended intracranially. The tumor was removed via a combined bifrontal transbasal and endonasal endoscopic approach. Her dural defect was also repaired with a free patch graft, and the ASB was repaired with a vascularized pericranial flap and an NSF. Her postoperative course was uncomplicated. After postoperative chemoradiation, her skull base repair remained intact at 3 and 6 months. Conclusion: The double flap technique provides an additional barrier of pedicled 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.