•Lissencephaly
–“Smooth brain” with reduced
number/absence of gyri and sulci
–Synonyms: agyria (absence of
gyri), pachygyria (thick gyri)
•Polymicrogyria
–Increased number of tiny gyri
with microscopic fusion of layer 1
–Must be distinguished from
increased gyral complexity, e.g., in hydrocephalus
•Heterotopia
–Laminar
–Periventricular