Hydrocephalus in Cats

Hydrocephalus is a neurological disease in which there is excessive accumulation of cerebrospinal fluid (CSF) within the ventricular system of the brain. The fluid in the brain (CSF) is normally formed in the brain. It bathes, protects, and circulates through the ventricular system within the brain and the coverings and is then absorbed into the circulatory system.

The production of CSF has an active and passive component; absorption is only a passive process. When the absorption of CSF is blocked or excessive fluid is produced, the volume of CSF increases. The increased CSF volume puts pressure on the brain, forcing it against the skull, damaging or destroying the tissues.

Symptoms of excess CSF volume vary with the cause, the age at presentation, the brain tissue being compromised, and the degree of tissue damage. In young animals, CSF can accumulate in the brain causing the fontanel (soft spot) to bulge.