Microcephaly with simplified gyral pattern: MRI classification.

Objectives: To develop subjective (visual) and objective (morphometric) rating scales for the classification of MRI in infants who had microcephaly with a simplified gyral pattern (MSGP) and to validate the first by the latter.

Methods: We compared the MRI of 12 patients with MSGP and of 5 term-born control infants. Visual rating and morphometric analysis was performed for gyration and associated brain abnormalities of basal ganglia, lateral ventricles, pons, cerebellum, and corpus callosum.

Results: Gyral pattern was rated reliably as normal in the control infants, simplified in 6 patients, and severely simplified in the other 6 patients. Associated brain abnormalities were reported in 10 of 12 patients. Visual rating correlated well with the morphometric measures.

Conclusions: Our visual rating scale for a simplified gyral pattern proved to be sensitive and reliable. Associated brain abnormalities are frequent, which underlines the need for a consistent scoring in these patients.