UCSF

Purpose: This research study sought to explore whether fetal total brain volume (TBV) determined by using conventional fetal MR imaging is associated with postnatal preoperative brain injury in neonates with critical congenital heart disease (CHD). A secondary aim was to investigate the trajectory of brain growth from the fetal to neonatal time period in this same patient population.

Methods: Twenty subjects had complex CHD diagnosed in utero and required postnatal neonatal surgery at University of California, San Francisco (UCSF) from 2010-2016. Fetal and neonatal MRI scans from 12 of the 20 eligible subjects were processed and analyzed in this study. These scans and clinical data are a part of an ongoing study to investigate the effects of CHD on brain injury and neurodevelopmental outcome at UCSF.

Results: This study revealed a strong linear relationship between fetal TBV and gestational age (p=0.0012). Subjects with preoperative brain injury tended to have a smaller mean fetal TBV (187.8 cm^3, 95%CI: 156.9-218.7) as compared to those without preoperative brain injury (225.2 cm^3, 95%CI: 189.8-260.6; p=0.165). There was also a trend towards decreasing TBV with a higher brain injury severity (BIS) score (BIS 0, TBV 225.1 ± 38.3 cm^3; BIS 1, TBV 210.9 cm^3; BIS 2, TBV 199.2 cm^3; BIS 3, TBV 176.4 ± 26.6 cm^3; p=0.06). The rate of increase in TBV from the fetal to neonatal time period was similar in those with and without preoperative brain injury (p=0.33).

Conclusions: These preliminary findings suggest a potential relationship between in-utero brain growth and the risk of neonatal preoperative brain injury in patients with critical CHD. A larger sample size will be analyzed to further assess this relationship.