FIG 4.

TUBA1A mutations (A–C). Case 18. T2-weighted single-shot FSE at 24 weeks 4 days' gestation. TUBA1A pathogenic heterozygous variant. The bilateral GEs are enlarged. The fronto-occipital diameter is 2.5, standard deviations below the mean. The corpus callosum and cerebellum are severely hypogenetic/hypoplastic. Underopercularization, severe ventriculomegaly, a thin kinked brainstem (A), a ventral pontine cleft suggestive of a Walker-Warburg phenotype, and apparent diencephalic-mesencephalic fusion or dysplasia (C) are also noted. D, Case 19 at 33 weeks. TUBA1A mutation with enlarged, cavitated GEs and abnormal persistence of hemispheric lamination.