Surgical results for spinal meningiomas

Abstract

Among a series of 782 spinal tumors, 130 spinal meningiomas in 117 patients were operated in the Department of Neurosurgery at the Nordstadt Hospital in Hannover, Germany, between 1977 and 1998. Patients were followed postoperatively for up to 13 years (mean 20 +/- 33 months). Comparing the period of 1977 through 1987, before magnetic resonance imaging (MRI) was available, to the period of 1988 to 1998 revealed that the average history until diagnosis shortened by about 6 months during the second decade of this study (24 +/- 33 to 18 +/- 29 months; not significant). Consequently, the preoperative Karnofsky Score increased significantly (59 +/- 15 and 66 +/- 16; p < 0.05). The rates of complete resection and the postoperative neurological outcome, however, remained unchanged. Even though the overall prognosis of neurological deficits is favorable after complete resection of a meningioma, a subset of 18 patients had either en plaque growing or recurrent tumors that were more likely to be removed incompletely and to cause postoperative neurological problems, with a significantly worse Karnofsky Score after 1 year (57 +/- 12 and 77 +/- 12, respectively; p < 0.01) and a significantly higher recurrence rate after 5 years (86.7% and 20.4%, respectively; log rank test p = 0.0014). In conclusion, a favorable postoperative neurological outcome requires complete resection of the spinal meningioma. The advent of MRI has shortened the time until diagnosis and made it possible to perform surgery before severe deficits have occurred, but did not have a major impact on postoperative results. En plaque and recurrent meningiomas remain surgical challenges, as infiltration of surrounding structures and associated arachnoid scarring may render complete resection difficult to achieve.