Noninvasive multimodal photoacoustic-ultrasound imaging for dynamic assessment of placental hypoxia and perfusion in preeclampsia.

Reliable methods for the non-invasive monitoring of placental status are essential for the management of preeclampsia. This study investigates the feasibility of multimodal photoacoustic-ultrasound (PA-US) imaging for the longitudinal assessment of placental oxygenation (sO2) and microvascular perfusion in a rat model. Our findings demonstrate that multimodal PA-US imaging parameters illustrate alterations in placental status non-invasively, which correlate strongly with histopathological markers, including hypoxia-inducible factor 1α (HIF-1α) and microvascular density (MVD). Besides, a characteristic inverted trajectory of imaging parameters during early gestation day 10-12 is observed. By enabling the simultaneous evaluation of oxygen and blood supply dynamics, multimodal PA-US imaging yields a more comprehensive view of placental function. Ultimately, these results suggest that multimodal PA-US imaging serves as a non-invasive and viable tool for detecting placental dysfunction and monitoring therapeutic responses in real time, laying a solid experimental foundation for advanced maternal-fetal care.