Female, 8 days old, ex-35 weeker, with prenatal ultrasound concerning for Dandy-Walker malformation, presenting with abnormal leg movements. Sibling with Dandy-Walker. The foramen of Magendie is slightly wide as visualized in the sagittal plane. This can represent normal variation or mild inferior vermian hypoplasia. The vermis is not upturned and the cerebellar hemispheres are normally formed. The posterior fossa is not enlarged.As appreciated in the sagittal plane, the tectum appears mildly prominent and the dorsal pons mildly thinned. These findings are not as conspicuous when viewed in the axial plane.The cerebral hemispheres are fully formed and demonstrate normal gyration for gestational age. No areas of signal abnormality or edema are seen. No generalized mass effect is detected. There are no findings to suggest acute intracranial hemorrhage or any abnormal extra-axial fluid collections. Diffusion-weighted images are within normal limits.The pituitary region is within normal limits. The corpus callosum is fully formed and unremarkable. The pattern of white matter myelination is appropriate or even somewhat advanced for the corrected gestational age.
1.No evidence of a classic Dandy-Walker malformation is seen. At most, the inferior vermis may be mildly hypoplastic but this could also reflect normal variation.2.As appreciated in the sagittal plane, the tectum appears mildly prominent and the dorsal pons mildly thinned. These findings are not as conspicuous on axial images which calls into question their validity. If real, such findings could reflect a mild midbrain patterning anomaly.3.Cerebral morphology is otherwise unremarkable. No focal or acute lesions are identified.