Evaluation of Neonatal Regional Cerebral Perfusion Using Power Doppler and the Index Fractional Moving Blood Volume

Abstract

Background: The high cerebral morbidity of premature neonates is thought to be related to changes in tissue perfusion in vulnerable areas of the brain. Quantification of power Doppler (PD) images using the index fractional moving blood volume (FMBV) may allow measurement of regional cerebral perfusion. Objective: To evaluate the reproducibility of calculating FMBV using PD ultrasound images to estimate cerebral perfusion. Methods: Two experienced clinicians performed head ultrasounds on 24 normally-grown neonates at less than 33 weeks’ gestation. Both clinicians independently acquired and stored three PD images in two different coronal planes. FMBV was calculated offline after selecting two predefined regions of interest within these planes (basal ganglia and subependymal regions). Reproducibility was evaluated by calculating the intraclass correlation coefficient (intraCC) and the interclass correlation coefficient (interCC). Results: FMBV was successfully evaluated in 24/24 neonates by both clinicians. The intraCC for repeatability for observer A was 1.00 (95% CI 1.00–1.00) for the basal ganglia and 0.99 (95% CI 0.99–1.00) for the subependymal region, and for observer B was 0.99 (95% CI 0.99–1.00) for the basal ganglia and 0.96 (95% CI 0.92–0.98) for the subependymal region. The interCC was 0.86 (95% CI 0.68–0.94) for the basal ganglia and 0.93 (95% CI 0.86–0.97) for the subependymal region. Conclusion: Using standardised settings and a well-defined region of interest, the calculation of FMBV using PD images is a reproducible method of estimating neonatal regional cerebral perfusion.