Noncontact optical assessment of spontaneous low-frequency fluctuations of cerebral blood flow in neonatal intraventricular hemorrhage

Intraventricular hemorrhage (IVH) is the most common neurological complication of prematurity. IVH is a bleeding inside or around ventricles, spaces in the brain containing the cerebrospinal fluid, which occurs as a result of the fragility and immaturity of blood vessels in premature brains. Severe IVH disrupts development of structural and functional connectivity networks, leading to impairments of cerebral development and neurologic deficits. Preterm infants with IVH are prone to alterations in cerebral blood flow (CBF) and associated spontaneous low-frequency fluctuations. However, there are no established noninvasive imaging methods for continuous monitoring of CBF alterations at the bedside in neonatal intensive care units. An innovative CCD/CMOS based speckle contrast diffuse correlation tomography (scDCT) technology has been recently developed in our laboratory, which enables noncontact, noninvasive, and high-density 3D imaging of CBF distributions in deep brain cortex. In the present study, the capability of scDCT technique for noncontact 3D imaging of CBF distributions in a neonatal piglet model of IVH was demonstrated. Moreover, power spectral density analyses of scDCT data were performed to assess alterations in spontaneous low frequency fluctuations in the resting brain, before and after inducing IVH. IVH resulted in a CBF decrease in deep brain cortex. Resting-state spontaneous low-frequency fluctuations after IVH showed attenuations in all frequencies (0.009– 0.08 Hz) compared to the baseline before IVH. In conclusion, scDCT is capable of detecting brain hemodynamic disruptions (reduction in CBF and attenuation in spontaneous low-frequency fluctuations) after IVH, which might be useful for instant management of IVH and associated complications.