Diffuse cortical malformations: agyria
, pachygyria, polymicrogyria, microcephaly, megalencephaly, microdysgenesis.
, calcifications (arrows), and ventriculomegaly in frontal lobes.
Walker first described the syndrome in 1942, noting agyria
, hydrocephalus, and eye malformations.
Lissencephaly may involve the complete absence of gyri (agyria
) or a reduction in the number of gyri.
Sixty-nine percent showed evidence of malformations of cortical development, including lissencephaly (relative smoothness of the brain surface) associated with pachygyria (poorly formed, broad cortical folds), agyria
(no cortical folds), or both (Figure 2, panel B).
(2016), where ZIKV positive fetus with microcephaly had almost complete agyria
, internal hydrocephalus, and calcifications in the cortex and subcortical white matter in the frontal, parietal, and occipital lobes (35).
is a condition that occurs as a result of silver particle impregnation of skin leading to blue-grey skin discolouration.
In pacygyria, there are areas where the brain is smooth, but it does not involve the complete agyria
that is present in lissencephaly.
(complete lissencephaly) or pachygyria (incomplete lissencephaly) as well as a thickened cerebral cortex are seen on imaging studies, differentiating lissencephaly from malformations of neuronal proliferation (Figure 23).
Based on the findings of the published reports, it appears three patterns of abnormalities are associated with maternal parvovirus B19 infection: positional limb deformities, radiographic evidence of intercranial calcifications, and dysplastic changes, including agyria
, macrogyria, polymicrogyria, and dysgenesis of the corpus callosum, he said.
There was almost complete agyria
with widely open sylvian fissures, and a small brain stem and cerebellum.
The supratentorial findings in these cases were hydrocephalus, corpus callosum agenesis, agyria
, cerebral atrophy, open lip schizencephaly and craniosynostosis.