Transfontanelle Thermoacoustic Imaging of Intraventricular Brain Hemorrhages in Live Sheep

Preterm neonates are vulnerable to periventricular-intraventricular hemorrhage since the periventricular germinal matrix blood vessels are still immature and fragile until around 36 weeks. While cranial ultrasound imaging (cUS) is the standard technique for diagnosing brain injury in neonates, it has limited accuracy in detecting early-stage hemorrhages due to poor sensitivity and specificity. Transfontanelle thermoacoustic imaging (TTAI) combines the advantages of high contrast from electromagnetic absorption with high-resolution from ultrasound imaging and represents a potential alternative to overcome the limitations of conventional cUS systems. We developed a TTAI system and evaluated its performance in a large animal model of intraventricular hemorrhage (IVH) in vivo. Our system demonstrated the ability to detect hemorrhages as small as 0.1 mL, which is better than the previously reported limit of detection for either ultrasound or photoacoustic imaging in the same animal model. These results indicate that TTAI is a novel imaging modality with high potential for accurate detection of IVH in neonates.