Early Experience with the Endoscopic Endonasal Approach in Pituitary Surgery

Introduction: Pure endoscopic endonasal approach (EEA) has replaced the recent years the traditional microscopic transsphenoidal approach (TSA) for resection of pituitary adenomas with superior results. We present the outcomes of EEA of the past 2 years that we consistently utilize this approach in our institution.

Methods: We retrospectively reviewed the medical files and imaging studies of 47 patients with pituitary adenomas who were managed with EEA between September 2014 and August 2016.

Results: Patients age ranged from 28 to 77 years (mean: 53). The maximum tumor diameter varied from 4 to 66 mm (mean: 24 mm). Four patients presented with microadenoma (8.5%), 36 with macroadenoma (76.6%) and 7 with giant adenoma (14.9%). Nonfunctioning pituitary adenomas represented 70.2% (33 cases) of the cases. Functional pituitary adenomas (14 cases) included 5 patients with acromegaly, 1 with Cushing’s disease and 8 with medication resistance/intolerance prolactinomas. Preoperative visual impairment was present in 14 patients (29.8%), pituitary deficiency in 15 cases (31.9%), while 6 patients (12.8%) presented with apoplexy. Unilateral or bilateral cavernous sinus invasion was observed intraoperatively in 28 cases. Gross total tumor resection was the goal in 46 cases and was obtained in 38 (82.6%). Total resection of tumor from invaded cavernous sinus was achieved with EEA in 77.8% of the cases. During the short mean follow-up of 6 months (range: 1–24 months), vision was improved or even normalized in 11 cases (78.6%) and remained unchanged in 3 (21.4%). Preexisting pituitary impairment was normalized in 3 patients (20%). Pituitary function remained intact in 96.9% of the cases; new pituitary insufficiency occurred in 1 patient (3.1%). All acromegalic and Cushing’s disease patients are in remission of disease following EEA. Among the eight prolactinomas, five patients have normal prolactin levels after surgery without medication and three patients required medical treatment. Complications included apoplexy of residual adenoma in 2 cases (4.2%), permanent diabetes insipidus in 1 (2.1%), cerebrospinal fluid leak in 2 (4.2%). One patient with sever comorbidities (malignant hypertension, morbid obesity, diabetes) developed respiratory failure 3 days after EEA, hypotension, vasospasm and stroke resulting in hemiparesis. In our limited experience with EEA, there was no carotid artery injury, meningitis, visual deterioration or death.

Conclusion: EEA has successfully replaced the traditional TSA in pituitary surgery with high rates of gross total tumor resection even when the cavernous sinus is invaded. Preservation of the pituitary function and even recovery of pituitary impairment can be achieved with EEA. Sever preexisting comorbidities can result in unsuccessful outcomes regardless of the surgical technique.

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