Spontaneous Congenital Hydrocephalus in Sprague Dawley Rat

Abstract

Hydrocephalus is a neurological disorder that results from the accumulation of excess cerebrospinal fluid in the ventricles of the brain culminating in an enlarged cranium. This sporadic disorder may occur as a congenital malformation in many mammalian species including inbred rodent colonies at an early juvenile stage of life. Under conventional husbandry practice of breeding, 5 pups showing some clinical signs of neurological dysfunction at the age of 20 days were examined thoroughly. Detailed macroscopic examination demonstrated dome shaped head, thinned and deformed parietal bone, open/closed suture depending upon the severity of ventricular dilatation. Microscopic examination revealed dilated lateral ventricles, compressed and attenuated cortical mantle, spongy appearance of the sub-ventricular zone, stretched ventricular ependyma, flattened ependymal cell lining and infiltration of mononuclear cells in the ventricular lining.