Assistant Professor Tufts Medical Center Tufts Medical Center Boston, Massachusetts, United States
Background: Isolated cerebral ventriculomegaly (IVM) is the most common fetal brain finding child neurologists see in prenatal counseling. However, its developmental outcomes are heterogeneous and difficult to predict.
Objective: In fetuses with IVM, we explored the correlations between quantitative fetal brain magnetic resonance imaging (MRI) measures and their postnatal 18-month developmental outcomes.
Design/Methods: We prospectively recruited 40 fetuses with MRI diagnosis of mild to moderate IVM (atrial diameter ~15 mm) and followed up their 18-month neurodevelopmental outcomes. We performed post-acquisition quantitative analysis of the fetal brain MRIs using regional volumetrics of the cortical plate, subcortical parenchyma, lateral and third ventricles, cerebellar hemispheres, and vermis. We performed a graph-based sulcal developmental pattern analysis, which quantified a normalized sulcal pattern similarity index (SI). The SI reflects how similar the geometric and topological sulcal features (position, area and depth of the sulcal basin, and sulcal graph topology or all combined) are in each brain compared to normal template fetal brains. Growth trajectories of fetal regional brain volumes were compared between fetuses who had abnormal (AB) and typical (TD) developmental outcomes by generating best fit non-linear regression models. We used unpaired Welch’s t-tests to test group differences in the sulcal pattern SI.
Results: Twenty-two of 40 fetuses have completed developmental testing in the age range of 18.4 ~ 22.7 months to date. Nine had abnormal outcomes; six with speech delay, three with behavioral problems, and three with motor delay (gestational age at time of MRI ranges 18.7 ~ 31.3 weeks of gestation). Thirteen had typical developmental outcomes (23.0 ~ 32.1 weeks). There were no significant differences in regional volume growth trajectories between the AB and TD groups, including lateral ventricular volume. In the left cerebral hemisphere, the AB group had lower SIs in combined sulcal features (p=0.015) compared to the TD group. In both hemispheres, the AB group had lower positional SIs compared to the TD group (left p=0.020, right p=0.013). Conclusion(s): In fetuses with IVM, more aberrant fetal sulcal development may correlate with poorer neurodevelopmental outcomes at 18 months. Fetal sulcal pattern SI could be used as an early neurodevelopmental biomarker. The outcome follow-up for the remaining subjects is ongoing.
Authors/Institutions: Tomo Tarui, Tufts Medical Center, Boston, Massachusetts, United States; Patricia Lee, Tufts Medical Center, Boston, Massachusetts, United States; Neel Madan, Tufts Medical Center, Boston, Massachusetts, United States; Rie Kitano, Tsuchiura Kyodo Byoin, Tsuchiura, Ibaraki, Japan; Shizuko Akiyama, Tohoku Daigaku Byoin, Sendai, Miyagi, Japan; Emiko Takeoka, Tufts Medical Center, Boston, Massachusetts, United States; HyukJin Yun, Boston Children's Hospital, Boston, Massachusetts, United States; George Graham, Tufts Medical Center, Boston, Massachusetts, United States; Osamu Samura, Tokyo Jikeikai Ika Daigaku, Minato-ku, Tokyo, Japan; Alexa Craig, Maine Medical Center, Scarborough, Maine, United States; Patricia E. Grant, Boston Children's Hospital, Boston, Massachusetts, United States; Kiho Im, Boston Children's Hospital, Boston, Massachusetts, United States