For a study, researchers sought to examine radiographic brain abnormalities and volumetric variations in persons born prematurely at a very low birth weight (<1,500 g), with siblings serving as controls.

They recruited 79 adult same-sex sibling pairs, one preterm with very low birth weight and the other at term. Three-dimensional brain magnetic resonance imaging was obtained from 78 preterm individuals and 72 siblings. A neuroradiologist blinded to the participants’ preterm status examined the pictures for parenchymal and structural abnormalities, and volumetric analyses were performed using FreeSurfer software 6.0. Linear mixed models were used to examine the data.

They discovered greater structural abnormalities in participants with extremely low birth weight than in siblings (37% vs. 13%). Periventricular leukomalacia was the most prevalent result, occurring in 15% of extremely low birth weight individuals and 3% of siblings. After normalizing for estimated intracranial capacity, the extremely low birth weight group had lower absolute brain volumes (-0.4 SD), less grey matter (-0.2 SD), bigger ventricles (1.5 SD), smaller thalami (-0.6 SD), caudate nuclei (-0.4 SD), right hippocampus (-0.4 SD), and left pallidum (-0.3 SD). There were no variations in overall white matter volume (-0.04 SD; 95% CI, -0.13 to 0.09).

Adults born prematurely with very low birth weight have a greater frequency of brain abnormalities than their term-born siblings. They also exhibited lower absolute brain volumes, less grey matter but not white matter, and lower volumes in various grey matter structures.