- Holoprosencephaly: spectrum of malformation due to failure of cleavage of forebrain
- Alobar, semilobar, lobar, Middle interhemispheric variant
- Alobar: complete absence of cleavage
Pancake of anterior cerebral tissue
Cresent shape mono ventricle communicating with a dorsal cyst
Fused thalami, more precisely uncleaved thalami
Absent corpus callosum