Focal Cortical Dysplasia Type 1

**Semantic type:** Finding

**Definition:** Focal cortical dysplasia characterized by abnormal cortical layering. It is associated with mild symptoms, late onset, and changes present in the temporal lobe. It includes the following: type Ia with abnormal radial migration and maturation of neurons; type Ib with disruption of the six-layered tangential composition of the cortex with immature neurons; and type Ic comprising both architectural abnormalities.

**Synonyms:** - FCD1 - FCDI - Focal Cortical Dysplasia Type I