The utility of the fronto-temporal horn ratio on cranial ultrasound in premature newborns: a ventriculomegaly marker

Background The aims of this study were to find the normal value of fronto-temporal horn ratio (FTHR) as a marker of ventriculomegaly on cranial ultrasound (CUS) in premature newborns and the relation to white matter injury (WMI) and cerebral palsy (CP). Methods This is a retrospective study of newborns admitted between 2011 and 2014. Inclusion criteria were: (1) gestation <29 weeks, (2) birth weight <= 1500 g, (3) referred within 7 days of life, (4) at least two CUS preformed, (5) brain magnetic resonance imaging (MRI) at term age-equivalent. Intraventricular hemorrhage (IVH) grade was identified and FTHR was measured on all CUS. WMI on MRI was evaluated through (1) injury score (Kidokoro 2013) and (2) fractional anisotropy (FA) on the MRI diffusion tensor imaging. CP was estimated using the gross motor function classification system (GMFCS). Results One hundred neonates met the inclusion criteria: 37 with no IVH, 36 with IVH grade 1-2, and 27 with IVH grade 3-4. The FTHR cut-point of 0.51 had the highest sensitivity and specificity for moderate-to-severe WMI. In the IVH grade 3-4 group, the elevated FTHR correlated with lower FA and higher GMFCS. Conclusions FTHR is a useful quantitative biomarker of ventriculomegaly in preterm newborns. It may help standardize ventricular measurement and direct intervention. Impact The fronto-temporal horn ratio has the potential to become a standardized tool that can provide an actionable measure to direct intervention for post-hemorrhagic ventricular dilation. This current study will provide the basis of a future clinical trial to optimize intervention timing to decrease the risk of white matter injury in this vulnerable population.