Cerebral High-Frame-Rate Ultrasound Imaging and Its Possibilities in the Neonatal Intensive Care Unit

Area of Science:

• Medical Imaging
• Neonatal Physiology
• Cerebrovascular Health

Background:

• Impaired cerebral blood flow in preterm neonates is a significant risk factor for brain injury.
• High-frame-rate (HFR) ultrasound (US) offers enhanced spatiotemporal resolution for flow analysis.
• HFR US has the potential to provide improved indicators of neonatal cerebral blood flow.

Purpose of the Study:

• To assess the feasibility of HFR US for measuring cerebral blood flow velocities in the periventricular zone of newborn infants.
• To differentiate between arterial and venous flow using HFR US.
• To investigate the impact of unilateral brain injury and patient variables on HFR US results.

Main Methods:

• A prospective cohort study involving (pre)term infants.
• 2-D HFR US imaging was performed using a custom HFR mode and a high-frequency linear probe.
• Offline analysis calculated peak systolic velocity (PSV), end diastolic velocity, resistivity index, and a novel flow index (FI).

Main Results:

• HFR US was performed in 81 patients, with 46 recordings yielding usable data.
• Arterial and venous flow were reliably distinguished.
• In neonates with unilateral intracranial pathology, the median FI was significantly higher on the affected side (p = 0.002).
• The flow index (FI) showed no significant correlation with birth weight, post-menstrual age, or mean airway pressure.

Conclusions:

• Qualitative and quantitative flow indices can be obtained using HFR US imaging in neonates.
• HFR-derived perfusion indices show promise in advancing the understanding and prevention of neonatal brain injury.