Overview
- Lissencephaly ("smooth brain") is a neuronal migration defect that manifests with a lack of sulci (and therefore poorly delineated gyri), so the head appears smooth.
- Although it is associated with microcephaly (an abnormally small head), lissencephalic babies typically have normal head sizes at birth, and thus, the term "microlissencephaly" is reserved for children who are born with both lissencephalic and microcephalic heads.
Associated Features:
- Severe psychomotor retardation
- Dysphagia (a reason for their failure to thrive)
- Amorphic facial appearance and digit deformation
- Muscle spasms
- Seizures
Syndromes:
Lissencephaly may be isolated or a part of -
- Miller-Dieker syndrome
- Walker-Warburg syndrome.