Brain Ventricles

Ventricles are fluid-filled spaces in the brain, and the brain contains 4 ventricles: Right lateral ventricle, Left lateral ventricle, Third ventricle, Fourth ventricle. Each ventricle has a structure called the choroid plexus that produces cerebral spinal fluid (CSF). 

CSF is produced by the choroid plexus and is found in brain ventricles and arachnoid spaces in the brain and spinal chord. The functions include protection, buoyancy, waste removal and transportation of nutrients and hormones. 

Hydrocephalus- means "water on the brain"; it is an accumulation of CSF which arises from an imbalance in the production and drainage of that fluid. The main symptom is a large head.