Microsurgical treatment of foramen magnum meningiomas

Abstract

Objective To report the clinical and radiological features as well as the surgical findings and outcomes for foramen magnum meningiomas (FFM) patients treated in the department of neurosurgery in Beijing Tiantan hospital over the last 15 years. Methods 114 consecutive cases of FFM operated between May 1993 and June 2008 were reviewed and followed up. Results Cervieo-occipital pain (80.7%), headache and dizziness (42.1%) were the most common symptoms. The mean duration of preoperative process was 11.7 months. The preoperative KPS was 72.5±8.3.All the FFMs were classified as anterior (80 cases), anterolateral (24 cases) and posterolateral (10 cases) types. The mean maximum diameter of tumors on MRI was (3.35±5.6)cm.The posterior midline approach was performed in 10 cases, far-lateral transcondylar or retrocondylar approach in 97 cases and extended far-lateral approach in 7 cases.Gross total resection was achieved in 86.0% of patients, and subtotal resection in 14.0%.Surgical mortality was 1.8%.Follow-up data were available for 93 patients, with a mean follow-up duration of 90.3 months (from 1 to 180 months). 59 (63.4%) patients lived a normal life (KPS, 80～100).Conclusions Most anterior and anteriolateral FFMs can be completely resected by far-lateral transcondylar or retrocondylar approach. Total removal of tumors should be attempted to achieved at the first operation. Postoperative management of FFM is important for prognosis. Key words: Foramen magnum; Meningioma; Microsurgery; Prognosis