Fetal brain in fetal growth restriction: alterations in cortical morphometry and volume.

OBJECTIVES

To evaluate fetal brain midline structures, cortical structures, and brain volume using sonography in cases of fetal growth restriction (FGR) and to compare these findings with those of fetuses demonstrating normal growth.

METHODS

This prospective case-control study included 80 FGR cases and 80 fetuses with normal growth curves between 24 and 37 weeks of gestation. Multiplanar neurosonography was performed in all cases according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) guidelines. The corpus callosum (CC; length, thickness, and fastigium distance), cavum septi pellucidi (CSP), sylvian fissure (SF), parieto-occipital fissure (POF), calcarine fissure (CF), insula, olfactory sulcus (OS), and brain volume were evaluated. Measurements were made using the ultrasound device's electronic calipers, and brain volume was calculated using the Virtual Organ Computer-aided Analysis (VOCAL) application.

RESULTS

In the FGR group, CSP width, CC length, and thickness were significantly increased, while CCFL and POF depths were decreased (p < 0.05, for all). Mean brain volumes were similar in the FGR and control groups (349.30 ± 61.77 vs. 368.42 ± 68.51, p = 0.066). In FGR group, middle cerebral artery peak systolic velocity (MCA PSV) was positively correlated with most brain structures but negatively correlated with CC thickness. There was no relationship between cerebroplacental ratio (CPR) and brain volume or fetal brain structures.

CONCLUSIONS

Our findings showed that FGR affects the fetal brain through neuroanatomical structures such as the CC, CSP, CCFL, and POF during the prenatal period. In our cohort, fetal brain volume did not differ significantly in FGR. Furthermore, there was no association between CPR and fetal brain structures.