Endonasal Anterior Skull Base Surgery: Pathologies, Results, and Complications
Objective: The increasing application of extended transsphenoidal approaches for a variety of indications mandates continued improvements in our understanding of anterior skull base approaches and their limitations. We performed a retrospective review of our experience with a spectrum of disease conditions treated by an extended endonasal endoscopic, or combined microscopic, anterior skull base approach.
Methods: From 2008–2013, 43 extended transsphenoidal procedures were performed for pathologies including: craniopharyngioma (17), pituitary adenoma (8), chordoma (4), Rathke's cleft cyst (3), meningioma (2), chondrosarcoma (1), fibrous dysplasia (1), germinoma (1), giant cell reparative granuloma (1), metastatic carcinoma (1), nasopharyngeal squamous cell carcinoma (1), spindle cell oncocytoma (1), and lesion with non-diagnostic characteristics (1). Technical nuances of the surgical approach and closure techniques were assessed, in relation to the anatomic extension of each lesion. Post-operative variables including re-operations, neurologic and visual function, endocrinologic function, presence of diabetes insipidus, vascular injury, and cerebrospinal fluid fistula were examined.
Results: Among 43 extended transsphenoidal cases, gross total resection was achieved in 15, radical subtotal resection in 13, and subtotal resection in 15. Following surgery, visual function improved in 13, remained stable in 21, and declined in 9 patients. Most of the visual declines improved with time, including a single patient with initial binocular blindness following surgery and 2 patients with hemifield slide due to severe bitemporal field deficits. New-onset permanent diabetes insipidus was noted in 9 patients. Significant vascular injuries included 1 instance of an ophthalmic artery pseudoaneurysm, 2 cases of cerebral infarction, 1 case of peri-tumoral subarachnoid hemorrhage and subsequent vasospasm, and 1 case of anterior epistaxis. Post-operative cerebrospinal fluid fistula was noted in 4 patients, with 2 resulting in re-operation for repair, after both had developed meningitis. 9 patients underwent subsequent surgery, 6 of whom were within 30 days of initial surgery while 3 were in a delayed fashioned for recurrence of tumor. 8 patients were readmitted and 1 mortality was noted within 30 days of surgery.
Conclusion: Extended transsphenoidal approaches represent a versatile tool in approaching suprasellar, parasellar, and retrosellar lesions, extending from the planum sphenoidale to the clivus. The gamut of potential risks should be tailored to the individual case scenario.