This is a front view of a baby’s brain showing the brainstem, cerebellum and cerebrum. Abnormalities include #1 size of the cerebrum and the posterior fossa structures (including brainstem and cerebellum) are equal. #2 There is absence of the sagittal fissure. #3 There is absence of the rhinencephalic structures including absence of both olfactory nerves. #4 Absence of sulci in the brain with the primitive gyral formation. Diagnosis: holoprosencephaly.