FIG 2. Normal coronal sections of the PF (superior to inferior). CA indicates calcar avis; Ch, choroid plexus; CH, cerebellar hemispheres; LV, lateral ventricle trigone; OH, occipital horn; OL, occipital lobe; SA, subarachnoid space; and T, tentorium.

A–C, Images in a neonate at 30 weeks’ gestational age.

A, The most superior coronal view.

B, The middle coronal view.

C, The inferior view.

D, Same section as in C in a neonate at 25 weeks’ gestational age shows a more rounded configuration of occipital horns and a wide (up to 15 mm) subarachnoid space with internal echogenic dots corresponding to vessels.