Myelopathy due to calcified meningiomas of the thoracic spine: minimum 3-year follow-up after surgical treatment.

OBJECT: Calcified meningiomas are an uncommon type of meningioma. This study details the clinical features, treatment, and follow-up of 11 calcified meningiomas treated from 2002 to 2009, for the purpose of providing general information, describing the skill required for the surgery, and detailing the imaging study of these tumors.

METHODS: Between 2002 and 2009, 11 patients underwent surgery for the treatment of calcified meningiomas. All were treated by the same group of doctors at the same institution, including surgery and rehabilitation after surgery. The minimum 3-year (> 36 months) follow-up data from the 11 patients were detailed. Neurological function was evaluated twice, based on the Frankel scale and Japanese Orthopaedic Association scoring system. The first evaluation occurred before surgery and the second 3 years after surgery.

RESULTS: In 3 cases, the Frankel score decreased by 1 level. In a comparison of the duration of preoperative symptoms, age, degree of canal stenosis, and intraoperative blood loss, it was found that the greater the degree of canal stenosis, the poorer the outcome of the patient. Calcified meningiomas were more likely to adhere to the nerves and dura, a finding that might explain the high incidence of neurological dysfunction and CSF leakage after surgery.

CONCLUSIONS: Calcified meningiomas are the most rare of all meningiomas. It appears that a greater degree of canal stenosis can lead to a poorer outcome. Computed tomography scans and MRI with contrast enhancement are recommended for intraspinal tumors before surgery to exclude the possibility of calcification. For calcified meningiomas, precise tumor resection, dura repair during surgery, and medical care after surgery are important for achieving an acceptable outcome.