1143: Is corpus callosum size affected in the setting of fetal growth restriction (FGR)?

Abstract

In fetal growth restriction (FGR), both small corpus collosa and brain sparing have been independently associated with adverse neonatal and long-term neurobehavioral outcomes. Objective: to determine if ultrasound-derived fetal corpus callosum length (CCL) was altered in a fetal growth restriction cohort. In this prospective cohort of 40 fetuses with EFWs < 10th%ile, the final ultrasound prior to delivery was used to obtain fetal biometry, CCL, and Doppler indices. According to 2016 International Society of Obstetricians and Gynecologists (ISUOG) guidelines, small for gestational age (SGA) was defined by an EFW in the 3–10th%ile with normal Dopplers (n=18) and FGR as those with EFW< 10th%ile with abnormal Dopplers (UA PI >95th %ile or CPR - < 5th %ile) or an EFW < 3rd %ile alone (n=22). The CCL was determined via reconstruction of images from transabdominal or transvaginal 3–D ultrasound sweeps. Since genetically small (normal) fetuses may have proportionally small CCLs, we adjusted by using head circumference (HC) as a comparison standard (CCL/HC). Statistical comparisons were made between CCL/HC of SGA and FGR fetuses, as well as CCL/HC vs MCA PIs (as a marker of brain sparing). We tested if CCL/HC is related to fetus type (SGA vs FGR; Wilcoxon rank-sum test) or MCA PIs (as a marker for brain sparing; linear regression). We performed a linear regression to evaluate the relationship between brain sparing and the corpus callosum accounting for head circumference and found it was not related (p=0.42). There was no significant difference between the CCL/HC for SGA vs FGR fetuses (p=0.58). Average gestational age was similar in both groups (mean = 33.8, SD = 3.08). CCL was not significantly different between FGR fetuses meeting ISUOG criteria versus SGA controls, nor did it correlate with MCA PI (brain sparing). Our findings suggest that CCL/HC is not affected by FGR or evidence of brain sparing. (Funded by the Perelman Family Foundation)View Large Image Figure ViewerDownload Hi-res image Download (PPT)