Quantification of Fetal Gyrogenesis in the Third Trimester. A Novel Algorithm for Evaluating Fetal Sulci Development

ABSTRACTBACKGROUND AND PURPOSEThe fetal brain changes significantly throughout gestation. From a smooth (lissencephalic) cortex, it transforms into its convolved (gyrencephalic) state. Despite its importance, the diagnosis of delay in brain gyrogenesis is a challenge for many sonographers. This study presents a novel semiautomatic image processing algorithm for simple quantification of sagittal sulci maturation in the third trimester.METHODSMid‐sagittal fetal brain ultrasound images were obtained during routine third trimester scans. Fetal brain sulci length measurements were performed using a novel semiautomatic image processing algorithm followed by manual measurements. Correlations between the total length of the sulci, gestational age, and fetal biometry were examined.RESULTSThe study included 64 patients. A significant positive linear correlation was found between total sulci length and gestational age (r = .658 for automated measurement, r = .7 for manual measurement, P < .0001). A similar relationship was found comparing total sulci length and fetal head circumference (r = .694 for automated measurement, r = .74 for manual measurement; P < .0001). A significant correlation was observed between automated and manual measurements (r = .947).CONCLUSIONSWe found that fetal gyrogenesis is linear throughout the third trimester of pregnancy. The use of a computer algorithm to measure fetal sulci can be used as a simple prenatal screening test for delayed gyral maturation of the fetal brain.