Tuberculum Sella Meningiomas: Surgical Outcomes, Endoscopic vs Open Approach, and a Proposed Tumor Grading Scale

Background: Tuberculum sella meningiomas are surgically challenging tumors that can cause severe visual impairment. Significant debate exists regarding the best approach to these lesions, whether transcranially or via an endoscopic transsphenoidal approach. Furthermore, there are relatively few large series comparing these approaches in the literature.

Objective: To review surgical outcomes after resection from two major academic medical centers and compare endoscopic transsphenoidal and open transcranial approaches with respect to surgical outcomes and visual function as well as complications. We also propose a tumor grading scale that takes into account tumor size, optic canal involvement and local arterial involvement, and then evaluate its predictive function and use in surgical planning.

Methods: A retrospective chart review was performed at both institutions from (1985–2015). The senior authors reviewed magnetic resonance images (MRI) from each tumor to confirm tuberculum sella location and grade the tumor based on the proposed grading scale. Logistic regression was used to evaluate surgical outcomes and the tumor grading scale.

Results: We identified 132 patients who underwent resection of tuberculum sella meningiomas, 104 from one center and 28 from the second center. Transcranial approaches were used in 87 (67%) of cases and endoscopic transsphenoidal approaches used in 45 (33%) of cases. Transcranial approaches included extended bifrontal (57%), orbitozygomatic (28%) and other (15%). Preoperative visual deficits were present in 67% of patients. Vision improved post-operatively in 48%, stayed the same in 34%, and was worse or unknown in 18%. Complications occurred in 19 (14%) of patients, including CSF leak (5%), infection (5%) and other complications (6%). The proposed scoring system found that tumors approached transcranially had significantly higher tumor score (size) and canal score (optic canal involvement) as well as total score compared with tumors approached transsphenoidally. There was no significant difference in the occurrence of any complication between the transcranial and transsphenoidal approaches, however, transsphenoidal approaches had a significantly higher rate of CSF leaks. Higher tumor score (p = 0.01) and pre-operative visual deficits (p = 0.0001) were significant predictors of worse visual outcomes after resection.

Conclusions: Tuberculum sella meningiomas are challenging tumors and can be graded with the proposed tumor grading scale that accounts for tumor size, optic canal involvement, and arterial involvement. Larger tumors scored higher on the scale and are more commonly approached transcranially, while smaller tumors with lower scores are amenable to endoscopic transsphenoidal resection. The majority of patients had improved or stable vision post-operatively. These results allow a standard way to systematically evaluate tumors and can inform surgeons as they consider how to approach these difficult lesions.