[A case of parkinsonian syndrome caused by normal pressure hydrocephalus accompanied by the cauda equina neurinoma].

A case of parkinsonian syndrome caused by normal pressure hydrocephalus (NPH) accompanied by cauda equina neurinoma is reported. A 69-year-old woman presented with typical symptoms of parkinsonism, including akinesia, resting and postual tremor, and cog-wheel rigidity. CT scan of the brain revealed dilatation of ventricles, but she did not present dementia and urinary incontinence that are common symptoms in NPH. Her cerebrospinal fluid (CSF) pressure was normal, and her protein level was high at 2,970 mg/dl. An electroencephalogram (EEG) showed diffuse slow waves. An IMP-SPECT images of the brain showed diffuse reduction of radioisotope uptake. Levodopa was not effective in treating her parkinsonism. Removal of the tumor caused dramatic improvement in her parkinsonism. Her CSF protein level was normalized and EEG and SPECT images were improved after the operation. However, ventricular size on brain CT showed no change. It was considered that the causal mechanism of NPH was due to high protein levels in the CSF. The parkinsonism in this case was caused by dysfunction of the circuits linking the cortex, basal ganglia, and thalamus associated with metabolic disorder due to periventricular ischemia. Typical parkinsonism caused by NPH associated with spinal cord tumor has not been reported. When we examine a patient with parkinsonian syndrome caused by NPH, we should check the CSF protein level. And if that level is high, the possibility of spinal cord tumor should be considered.