RESUMEN
Neurinoma of cauda equina associated with normal pressure hydrocephalus is rare with only 13 cases reported in the literature. A 65-year-old man was operated for lumbar neurinoma, revealed by cauda equina syndrome. On the 15[th] postoperative day, the patient presented neurological stagnation, with mental deterioration. Cranial CT-scan showed tetraventricular hydrocephalus. Following insertion of ventriculoperitoneal shunt, we observed good amelioration of neurological deterioration. Twelve months postoperatively, the patient regained full neurological function. Many hypotheses were presented but alteration of craniospinal compliance distribution and the increase in CSF protein content are the most widely accepted theories explaining this association