<unk> s are cerebrospinal fluid covered by<unk> al cells and collagen that may develop between the surface of the brain and the cranial base or on the<unk>  membrane, one of the three meningeal layers that cover the brain and the spinal cord. Primary<unk> s are a congenital disorder whereas secondary<unk> s are the result of head injury or trauma. Most cases of primary cysts begin during infancy; however, onset may be delayed until adolescence.
Arachnoid cyst
Subdural hygroma
Labyrinthine fistula
Frontal horn cyst
Cystic hygroma
Choroid plexus papilloma
Choroidal fissure cyst
Hemicrania continua