Cerebellar abnormalities of preterm infant treated with postnatal corticosteroids

Ultrasound (A) and MRI scans (B and C) of preterm infant (gestational age 26 weeks) at term equivalent age who was treated with postnatal corticosteroids.
A) Coronal plane through mastoid fontanel.
(B and C) T2- (B) and susceptibility-weighted (C) MRI at midcerebellar level. The T2-weighted scan shows generalized cerebellar underdevelopment as the transcerebellar diameter (B) is too small for this age (42.4 mm, normal range 50 to 55 mm) and the subarachnoidal space around the cerebellum is too wide. The susceptibility-weighted scan (C) shows blood residue within the 4th ventricle (arrow), possibly extending from supratentorial IVH, but no CBH.