Abnormal orbitofrontal development due to prematurity.

OBJECTIVE

To investigate the effects of prematurity on sulcal formation.

METHODS

We evaluated the depth and volume of the primary olfactory sulcus (developed at 16 weeks' gestation) and the secondary orbital sulci (which start to develop at 28 weeks' gestation) in a sample of 22 adolescents with history of very-preterm birth (VPTB). We compared this preterm sample with a sample of subjects born at term and matched by age, gender, and sociocultural status. The Anatomist/BrainVISA 3.0.1 package was used to identify and quantify the sulci. In addition, voxel-based morphometry (VBM) was used to analyze possible reductions of gray and white matter in the orbitofrontal area.

RESULTS

Compared with controls, we found a significant reduction in the secondary sulci depth but not in the primary sulcus in the VPTB. VBM analysis showed reduced gray-matter volume in VPTB in the orbital region.

CONCLUSIONS

Premature birth affects cerebral gyrification, and this impairment is not reversible during childhood. Identification of the specific factors involved in abnormal brain maturation may lead to effective interventions.