Clinical Outcome after Endoscopic Endonasal Resection of Planum and Tuberculum Sella Meningiomas

Background: The endonasal approach (EEA) has been recognized as an effective approach for resection of tuberculum sella meningioma (TSM) in select cases. Few large case series have been reported. We present our experience in a large series of cases and discuss surgical outcomes and case selection, surgical limitations, and technical nuances.

Methods: 25 consecutive cases of TSM treated by the EEA from 2008 to 2016 were retrospectively reviewed. Information was collected regarding patient demographics, surgical history, clinical presentation, radiographic characteristics, extent of resection, surgical complications, tumor recurrence, and endocrine and visual outcome.

Results: Mean patient age was 53.9 (range 26–80) years with clear female predominance (84%). Preoperative vision impairment was seen in 80% of patients. Mean tumor volume was 5.3 cm3. Tumor location was isolated to the tuberculum sella in 8 (32%) cases and involving the tuberculum and planum 17 (68%) cases. Optic canal invasion was present in 17 (68%) patients. The anterior cerebral artery (ACA) was partially encased in 4 (16%) cases, and abutting in 13 (52%) cases. The supraclinoid internal carotid artery (ICA) was partially encased in 7 (28%) cases, and completely encased in 4 (16%) cases. Three cases presented with co-incidental pathologies including Cushing’s disease, Rathke’s cleft cyst, and an ophthalmic artery aneurysm. Gross total resection (GTR) was achieved in 19 patients (74% of all cases and 95% of those planned for GTR preoperatively). Complete encasement of the ICA was the reason for near or subtotal resection in most cases. Optic canal invasion, tumor volume and partial vascular encasement were not limiting factors for GTR. Mean follow up 21 months. No tumor recurrence was seen. One patient with residual tumor developed progression in follow-up, requiring fractionated stereotactic radiotherapy. 88% of the patients with visual impairment before surgery had improvement or even normalization of vision and 12% were stable. While four (16%) patients had transient visual deterioration, no patient had permanent visual deterioration in follow-up. Median and mean length of hospital stay was 4.0 and 6.6 days respectively. Cerebrospinal fluid leak occurred in 2 (8%) cases. One case resolved with lumbar drain alone and the other patient underwent endonasal repair. No patient had meningitis after surgery. Transient diabetes insipidus (DI) occurred in 3 cases, but no patient had permanent DI or new anterior pituitary dysfunction. One patient had a pulmonary embolism (PE).

Conclusion: This study represents the second largest series of tuberculum sella meningiomas treated by an endoscopic endonasal approach. The results of our study demonstrate that the EEA can provide high rates of complete resection and visual improvement with low rates of complications. Tumor relationship to the optic nerves, ACAs, ICAs, extension into the sella and/or sphenoid sinus must be carefully evaluated to appropriately select cases for the EEA. Better results and fewer complications may be achieved at higher volume centers with an experienced cranial base team.