Objective Recently, cerebellum has been ascribed an important role for cognition. Low cerebellar volumes in preterm infants at term have been associated with cognitive and motor development at 2 years of age. Intrauterine growth restriction with abnormal fetal blood flow (AFBF) is a known risk factor for later neurological sequelae. We wanted to study if birthweight small for gestational age (SGA) and AFBF are associated with decreased cerebellar volume at term.
Methods We studied 51 infants with a gestational age of (mean ± SD) 26.2 ± 1.9 weeks and a birth weight of 853 ± 276 g using magnetic resonance imaging at term (40.1 ± 0.6 gestational weeks). Cerebellar volumes were measured by manual outlining using a special image analysis tool (www.slicer.org) on transversal slices on both T1 and T2-weighted images.
Results The cerebellar volume at term correlated strongly with gestational age at birth (r = 0.518, p<0.001), birth weight (r = 0.631, p<0.001) and birth weight z-score (r = 0.379, p = 0.006). Cerebellar volume was lower for SGA infants (n = 15, 19.1 ± 3.7 ml vs 22.0 ± 3.4 ml, p = 0.009) and for infants with AFBF (n = 8, 18.1 ± 3.1 ml vs 21.8 ± 3.6 ml, p = 0.009), compared with infants without SGA or AFBF, respectively. After correction for gestational age, both SGA (p = 0.002) and AFBF (p = 0.003) were significantly associated with decreased cerebellar volume. No gender differences were observed.
Conclusions AFBF and birthweight SGA are associated with decreased cerebellar volume at term, independently of prematurity. This might contribute to the increased risk of adverse neurological and cognitive outcomes present in these children.