Skull Base Repair and Extent of Pituitary Adenoma Removal

Introduction: Endoscopic endonasal removal of pituitary adenomas requires entrance into the inferior skull via the nasal passage, and penetration of the skull base via the sphenoid bone and sella. Care must be taken to repair the skull base penetration, to prevent meningitis or leakage of cerebrospinal fluid. Two prominent reconstruction methods are utilized: the nasoseptal flap, which requires an initial graft from the nasal septum prior to tumor removal, and the smaller free mucosal graft which can be done at any point in the procedure. In this study, we compare the postoperative rates of both residual and recurrent pituitary adenoma between patients who undergo nasoseptal flap repair and patients who undergo free mucosal graft repair.

Methods: Following IRB approval, a retrospective chart review was conducted on pituitary adenoma patients (n = 216). The type of skull base repair conducted was noted, as was the presence of postoperative residual or recurrent tumor.

Results: Out of 216 total pituitary adenoma patients, 176 patients underwent nasoseptal flap repair and 40 patients underwent free mucosal graft repair. Patients receiving a nasoseptal flap repair had an ~41% rate of residual tumor, and 7% rate of recurrence. Patients receiving a free mucosal graft repair had an ~23% rate of residual tumor, and 3% rate of recurrence. The difference between the two groups' rates of residual tumor was significant (p < 0.05), while the difference in rates of recurrent tumor was nonsignificant (p = 0.25).

Conclusion: We initially expected the nasoseptal flap technique to be associated with a reduced degree of residual or recurrent tumor, believing that the larger amount of tissue harvested initially would allow the surgeon to be more aggressive in removing tumor tissue. However, we found the opposite result, which suggests that nasoseptal flap reconstruction is more associated with residual tumor. Though we suspect that this result is due to the nasoseptal flap technique being used in more complex pituitary adenoma cases, this study demonstrates the need for more extensive research and review of patients undergoing transsphenoidal pituitary adenoma removal.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
12 February 2021