FIG. 2.

Sagittal T2-weighted (A) and T1-weighted (B) MRI revealing a relatively large skull in relation to the spine, accompanied by retroflexion of the head. An occipital bone defect at the foramen magnum is evident, associated with a large cephalocele containing a very small hypoplastic cerebellum and a significant amount of CSF exhibiting increased signal intensity on T2-weighted imaging, all surrounded by meninges. Notably, there is enlargement of the posterior lobe of the pituitary gland, consistent with the infant’s age group, showing a normal marked increase in signal intensity on T1-weighted imaging. These features are indicative of iniencephaly apertus.