[A case of intramedullary spinal schwanoma (author's transl)]

A rare case of intramedullary schwannoma of the spinal cord has been reported, The patient was a 30-year-old woman, who began to notice weakness in her right leg approximately 6 months prior to admission, followed 4 months later by numbness and weakness of the right arm. The above symptoms were progressively getting worse, and she was admitted to Hokkaido University Hospital on February 23, 1974. Neurological examination revealed slow speech, bilateral horizontal nystagmus, absent gag reflex and weakness of right trapezius muscle. Spasticity was noted in 4 extremities, in addition to right hemiparesis. All deep tendon reflexes were hyperactive, right more than left, with bilateral Hoffmann's and Babinski's signs. Vibration sense was diminished below the level of bilateral iliac crests. A tumor around the foramen magnum was suspected, however plain skull and neck, laminogram of cervical spines, vertebral arteriogram, fractional pneumoencephalogram and myodil myelogram failed to disclose abnormalities. Manometric Queckenstedt test showed a partial block on flexion, with CSF protein of 56 mg/dl. Air myelogram clearly visualized the presence of an intramedullary tumor at the level of the medullo-spinal junction. Subtotal removal of the intramedullary tumor at C1 was performed, which proved to be a schwannoma histologically. 14 such cases are reported in the literature and summarized on Table I, including our case. Clinical features of tumors around the foramen magnum are fairly complexed, and some radiological examinations might not be conclusive. It is stressed that air myelogram is extremely valuable in the diagnosis of lesions around the foramen magnum.