The Endoscopic Buccal Fat Pad Flap for Closure of Skull Base Defects: A Report of Three Cases

Objectives: The nasoseptal flap is the workhorse flap for skull base reconstruction following endoscopic extirpation of skull base tumors. It can cover defects of the anterior skull base, sella, and clivus down to the craniovertebral junction with an acceptably low CSF leak rate of ~5%. However, the nasoseptal flap is not always available. Alternate flaps have been described with different profiles of advantages and disadvantages. We recently described the endoscopic anatomy and harvest of the buccal fat pad flap in a cadaver model, but the use of this flap in a clinical setting has not been previously reported. We report four consecutive cases of the endoscopic buccal fat pad flap.

Methods: Four cases managed with an endonasal harvest and use of the buccal fat pad flap were reviewed retrospectively. The surgical approach involved a medial maxillectomy with removal of the posterior wall of the maxillary sinus endoscopically. This allowed exposure of the buccal fat pad and its pedicle at the termination of the internal maxillary artery. Distal terminal vessels were ligated and the buccal fat pad was dissected free from surrounding musculature (temporalis and medial pterygoid) allowing it to be either advanced, or pedicled and rotated to cover the defect.

Results: The endoscopic buccal fat pad flap is used as an advancement flap to cover the greater sphenoid wing and foramen ovale in three cases and as a pedicled flap to cover the clivus in one case. The patient with the clivus defect underwent an endoscopic nasopharyngectomy for a recurrent nasopharyngeal cancer after previous radiation therapy. Cancer involved the posterior septum, and therefore a nasoseptal flap was not available. The buccal fat pad flap was harvested and pedicled to provided sufficient length to cover the clival and C1 defect. The other three cases involved defects in the pterygopalatine fossa and infratemporal fossa after tumor resection (leiomyosarcoma, metastatic neuroblastoma, and metastatic papillary thyroid cancer). The defects covered included the medial pterygoid muscles and greater sphenoid wing bone (all three cases) and foramen ovale dura (two cases). The buccal fat pad, which was exposed in the approach to these three tumors, was readily accessible and advanced to cover the extirpative defects. All four of the patients had complete take of the buccal fat pad flaps with mucosalization on post-operative follow up.

Conclusion: This is the first report of application of the endoscopic buccal fat pad flap. The buccal fat pad is a useful alternative flap available in the surgical field with a hearty blood supply based on the internal maxillary artery. Our early experience in four cases suggests the flap is viable, aids in the healing postoperatively, and is a useful addition to the armamentarium of the skull base surgeon.