[Neurinoma of the cauda equina associated with normal pressure hydrocephalus].

Hydrocephalus associated with spinal tumors is a well known but not common phenomenon. Over 80 such cases have been reported since 1931 by Kirieleis. Most of those cases present features of raised intracranial pressure, for instance papilledema. The histological diagnosis of the tumors is ependymoma (1/2), neurinoma (1/4) and malignant astrocytoma (1/4). On the other hand dementia as a symptom of spinal tumors has been reported only 13 times. In 11 of 13 cases presented with signs of NPH, mental status improved only by removal of the tumors without shunt operation. The histological diagnosis of the tumors is neurinoma (9 cases), ependymoma (2) and meningioma (2). Ours is the 14th case. A 59-year-old woman presented a 6 month history of memory disturbance, gait disturbance and urinary incontinence. CT scan showed ventricular dilatation. RI cisternography revealed a block at lumbar region. CSF obtained by lumbar puncture was deep yellow and turbid. CSF protein level was markedly elevated to 4073 mg/dl. MRI of the spinal cord demonstrated cauda equina mass. Total removal of the spinal tumor was performed. The histological diagnosis was neurinoma. Within 3 weeks the patient's symptoms had dramatically improved. The decrease in ventricular size was noted on CT 18 months after operation. We think one of the most important factors by which spinal tumors develop NPH is elevation of the CSF protein content. In our case, postoperative protein level decreased from 4073 to 274 mg/dl.(ABSTRACT TRUNCATED AT 250 WORDS)