gms | German Medical Science

Objective: To evaluate long-term clinical outcome and response after gamma knife radiosurgery (GKRS) of cavernous sinus meningiomas.

Methods: In 52 consecutive patients harboring meningiomas involving the cavernous sinus GKRS had been performed at least five years prior to assessment of this study. One patient was lost to follow-up review, leaving 51 analyzable patients with clinical and imaging follow-up. Forty two patients (82%) underwent adjuvant radiosurgery after one or more operations. In nine cases (18%) GKRS was the primary treatment for tumors < 18 cm³. The median age was 53 years, the male to female ratio 11:40. A median dose of 13 Gy (range 12–15 Gy) was applied to the tumor margin. The optic pathways received less than 8 Gy in all cases. Pre- and post-interventional neurological symptoms were examined by interview or questionnaire: symptoms as headache, nausea, vertigo, diplopia, visual and olfactory disturbances were requested.

Results: At follow-up examination (15–98 months, median 64) neurological status was improved in 48% of the patients and stable in 46%. Mild transient symptoms such as trigeminal dysaesthesia were reported in 6%. However, no permanent neurological aggravation was observed at follow-up. Tumor volumes as measured in MRI (1, 4–18.1 cm³, median 6.9 cm³) decreased in 60% and remained unchanged in 36%. Two patients (4%) had out of field recurrences after more than 60 months follow-up.

Conclusions: GKRS provides a safe and effective management of cavernous sinus meningiomas. GKRS as primary treatment can be considered as an alternative to microsurgical removal of small to medium sized (smaller than 18 cm³) cavernous sinus meningiomas without compression of the optic pathways. In case of extensive meningiomas it should be proposed as adjuvant to surgery.