Ossified spinal meningiomas: Clinical and surgical features

Abstract

Object: Meningiomas constitute 25% of primary spinal tumors and predominantly involve the thoracic spinal cord. Although calcifications are commonly seen in intracranial meningiomas, gross calcifications are observed in only 1-5% of all spinal meningiomas. We report the clinical findings, surgical strategy and histological features of 9 patients with ossified spinal meningiomas (OSMs).

Patients and methods: Clinical and surgical features of 9 patients with ossified spinal meningiomas were retrospectively reviewed.

Results: There were 8 women and 1 man with a mean age of 59 years. In 7 patients, the lesions were localized in the thoracic segment of the spine while in 2 patients in the lower cervical segment. All patients presented with weakness of the lower limbs and hypoesthesia below the site level of the lesion. Only 2 patients presented with urinary incontinence. Gross-total resection of the tumor was achieved in 6 patients while in 3 a subtotal removal of the meningioma was obtained. In all patients the postoperative course was uneventful. Six patients presented with a significant neurological improvement while in 3 patients a mild improvement was observed. Microscopically, all tumors showed typical histological pattern of ossified meningioma.

Conclusions: OSMs are amenable to surgery if the complete removal can be achieved. Because of their hard-rock consistency complete resection can be challenging. In difficult cases, subtotal removal can be advised and follow-up imaging is mandatory. Overall, the risk of long-term recurrence of the lesions is low, and a good clinical outcome after total or subtotal removal can be expected.

Keywords: Gross total resection; Metaplastic meningioma; Ossified spinal tumor.