periventricular nodular heterotopia
Pronunciation: per-ih-ven-TRIK-yoo-lar NOD-yoo-lar het-er-oh-TOH-pee-ah
Also written as: PNH — periventricular nodular heterotopia
A neuronal migration disorder where clusters of neurons remain near the ventricles instead of migrating to form normal cortex.
Full Definition
Periventricular nodular heterotopia (PNH) is a neuronal migration disorder characterized by nodules of gray matter located along the lateral ventricles. These neurons failed to migrate properly during fetal brain development, remaining in clusters near the ventricles rather than forming the normal cortical layers. PNH is often associated with epilepsy and can be either sporadic or inherited, particularly through X-linked mutations in the FLNA gene. The condition may present with seizures, developmental delays, or may be discovered incidentally on neuroimaging.
Usage
Usage note: Always written in lowercase except when abbreviated as PNH. Distinguish from other migration disorders by specifying the periventricular location.
In Context
- "The MRI revealed bilateral periventricular nodular heterotopia consistent with the patient's refractory epilepsy." — Radiology report
- "Genetic testing confirmed X-linked periventricular nodular heterotopia due to a FLNA mutation." — Clinical genetics consultation