Visual outcome of tuberculum sellae meningiomas after extradural optic nerve decompression

Meningiomas of the tuberculum sellae have a close relationship with the optic apparatus. Even modern series show a 10 to 20% risk of visual deterioration after surgery. We have attempted to improve visual outcome by extradural decompression of the optic canal and anterior clinoid process, followed by intradural release of the optic nerve; this study provides an analysis of visual outcomes with this approach.

Treatment, histopathology, and follow-up data of 29 consecutive patients undergoing surgery for tuberculum sellae meningiomas with initial release of the optic nerve were prospectively collected.

Radical tumor removal was possible in all 23 patients with primary tumors and in three out of six patients with recurrent tumors. All patients but two of the worst affected with preoperative visual compromise improved from surgery; there were no instances of visual deterioration. Five patients with normal preoperative vision remained intact and visual improvement was 22 (91%) out of 24 patients in the remaining patients. In total, 13 patients (42%) had completely normal vision at follow-up. Mainly patients younger than 60 years experienced complete normalization after surgery. Two patients underwent transsphenoidal surgery for cerebrospinal fluid leaks. Postoperative endocrinological symptoms were temporary diabetes insipidus in one patient and permanent diabetes insipidus in another patient undergoing elective sectioning of the pituitary stalk because of a recurrent tumor with invasive growth into the stalk.

Adding early optic nerve decompression by extradural clinoidectomy and optic canal unroofing to a frontopterional approach seemed to improve visual outcomes because there were no instances of visual deterioration. Simpson Grade 1 to 2 removal was possible in all patients with primary surgery, whereas recurrent cases could only be treated with lower grades of radicality. Radical removal, however, required readiness to reoperate for cerebrospinal fluid leakage at the site of the drilled tumor origin in bone.