High incidence of optic canal involvement in tuberculum sellae meningiomas: rationale for aggressive skull base approach.

BACKGROUND: Current literature on TSMs underemphasizes the significance of OCI by the tumor. In this study, we aimed to document the incidence of OCI, its management using a SBT, and its significance with relation to the visual outcome.
METHODS: Thirty-one patients with TSM were retrospectively analyzed. In 28 patients, SBT consisting of extradural anterior clinoidectomy with falciform ligament and optic nerve sheath opening was performed. Pre- and postoperative visual status was analyzed with respect to OCI.
RESULTS: The incidences of OCI and preoperative visual deficit (VD) were 77.4% and 83.8%, respectively. With regard to preoperative visual status, OCI incidence was 84.6% in 26 patients with VD compared to 40% in 5 patients without (P = .016). Among the 23 patients with VD and detailed postoperative neuroopthalmologic evaluation, 78.3% had visual improvement; and in 21.7%, vision was unchanged on the operated side. In one patient (3.2% in the whole series), vision deteriorated on the side contralateral to the side of surgery. In the presence of OCI in 20 patients, vision improved in 80% and remained unchanged in 20%, whereas 1 of the 3 patients without OCI improved and the other 2 remained unchanged. Simpson grade I or II resection was achieved in 83.8%.
CONCLUSION: Optic canal involvement is very common in TSM (77.4%), and it correlates well with preoperative visual status. With the use of SBT, without which the tumor in the optic canal could not have been removed completely and safely, visual improvement of 78.3% and stability of 21.7% were achieved on the operated side.