A colloid cyst is a type of brain cyst that forms from the build-up of a gel-like material in the brain's ventricles. Synonyms for colloid cyst include neuroepithelial cyst, third ventricle cyst, intraventricular cyst, and intracranial cyst. These types of cysts are relatively rare but can cause serious neurological symptoms if they grow in size or obstruct the flow of cerebrospinal fluid. Treatment options for colloid cysts may include surgical removal, endoscopic procedures to drain the cyst, or monitoring the cyst with periodic imaging studies. It is important for individuals with suspected colloid cysts to seek medical evaluation and appropriate treatment.