Gray matter heterotopia Periventricular heterotopia Subependymal grey matter heterotopia UMLS:C1849173 A form of gray matter heterotopia were the mislocalized gray matter is typically located periventricularly, also sometimes called subependymal heterotopia. Periventricular means beside the ventricles. This is by far the most common location for heterotopia. Subependymal heterotopia present in a wide array of variations. There can be a small single node or a large number of nodes, can exist on either or both sides of the brain at any point along the higher ventricle margins, can be small or large, single or multiple, and can form a small node or a large wavy or curved mass. Subependymal gray matter heterotopia Subependymal neuronal heterotopia Periventricular neuronal heterotopia Periventricular gray matter heterotopia can be seen for example in patients with Smith-Lemli-Opitz-Syndrome. HP:0007165 HP:0002272 Periventricular gray matter heterotopia Periventricular grey matter heterotopia