Laser Ultrasound Super-Resolution Imaging for Multi-Parametric Non-Invasive Volumetric Characterization of Brain...

Accurate characterization of brain tumor heterogeneities and microvascular dynamics remains an unmet need in cancer research driving the development of innovative imaging methods. Here, laser ultrasound super-resolution imaging (LUSSI) is introduced, a hybrid modality combining laser-generated ultrasound with optoacoustic (OA) contrast to enable functional volumetric (3D) super-resolution imaging of vascular structures in vivo. The system integrates a laser ultrasound (LUS) emitter and a spherical array transducer to localize microbubble responses in 3D, further enabling concurrent acquisition of multi-spectral (multi-wavelength) OA data. The capabilities of LUSSI to assess tumor heterogeneities are demonstrated in a murine glioblastoma model, including visualization of intra-tumoral vasculature, identification of compressed vessels, and detection of functional abnormalities such as hemorrhages and hypoxic regions. OA imaging further enables resolving oxygenated and deoxygenated forms of hemoglobin, revealing heterogeneous perfusion within the tumor core. LUSSI is further shown to resolve whole-brain vascular networks with ≈35 µm resolution and quantify microvascular blood flow and oxygenation, supporting applications in neuroscience. With its non-invasive, multi-parametric capabilities and proven compatibility with clinical imaging components, LUSSI offers a promising platform for studying vascular pathology, monitoring therapy, and advancing translational imaging strategies.