Neurofibrillary tangles in association with congenital hydrocephalus.

Morphologic study of the brain from a retarded patient with progressive congenital hydrocephalus revealed widespread neurofibrillary tangles in the cerebral cortex and the brain stem. Senile plaques were not found. The tangles consisted of paired helical filaments. Scanning electron microscopic energy spectrometric analysis failed to demonstrate abnormal accumulation of aluminum or other elements in the involved neurons.For the first time the association of congenital hydrocephalus and neurofibrillary tangles is reported. This observation is consistent with the hypothesis of interference with axonal transport of neurofilaments as a common pathogenetic mechanism in the genesis of neurofibrillary tangles in human brains.