Intramedullary spinal cord tumors resected with CO2 laser microsurgical technique: recent experience in fifteen patients.

We have operated upon 15 intramedullary spinal cord tumors with the aid of a CO2 laser attached to the microscope. The operative technique is described. Most of the tumors were localized within the cervical spinal cord. Nine tumors were benign gliomas: 4 ependymomas, 1 subependymoma, 3 astrocytomas, and 1 ganglioglioma. Six were removed totally, and 3 were removed subtotally. The remaining 6 tumors consisted of 3 hemangioblastomas, 1 intramedullary neurofibroma, 1 lipoma, and 1 primary intramedullary melanoma. Neurological function postoperatively compared to the preoperative function of the upper extremities was unchanged in 13 patients (86.5%), improved in 1, and worse in 1 patient. In the lower extremities, the preoperative neurological status was unchanged in 11 patients (73.3%), improved in 1 patient, and worse in 3 patients (20%). Magnetic resonance imaging was superior to myelography and computed tomography in localizing these lesions. Enhancement with paramagnetic substances (e.g., gadolinium-DTPA) helps to localize solid tumor within cysts. Histological evaluation of small tissue biopsies or frozen section histology is unreliable. The entire lesion should be exposed in all cases, and an attempt should be made to remove the tumor totally or, if this is not possible, to resect as much of the center of the tumor as is possible until the cord is decompressed. The decision to administer further treatment is based on the histological features of the tumor.