High-Resolution Angiography and Vascular Imaging in the NIR-II Spectrum

Non-Invasive Hemodynamic Profiling and High-Contrast 3D Network Reconstruction

Preclinical study of the cardiovascular network requires optical systems that can bypass the strong scattering and autofluorescence inherent to biological tissue. Photon etc.’s advanced short-wave infrared (SWIR) and NIR-II in vivo imaging platforms provide a definitive solution by operating in the 900–1700 nm optical window, where mammalian tissue achieves maximum transparency. By combining ultra-low-noise deep-cooled InGaAs camera sensors with high-intensity laser excitation, our instruments allow researchers to capture the fine architecture of blood vessels at unprecedented structural depths. This capability shifts the paradigm of optical angiography from superficial monitoring to high-contrast, sub-millimeter deep-tissue examination.

The definitive power of our platforms is highlighted when paired with state-of-the-art contrast agents, such as tailorable gold nanoclusters (AuNCs). As demonstrated in leading nanobiomedical research [1], rigidifying the surface ligands of these NIR-II emitting nanoclusters substantially shifts and optimizes their photoluminescence profile. Our high-sensitivity detection instruments seamlessly capture these enhanced emissions across specific infrared bands. Combined with deep-learning-assisted processing, this synergy enables the reconstruction of high-definition, pseudo-3D vascular networks in vivo, providing researchers with clear, high-contrast, volumetric maps of complex circulatory structures that are typically invisible to conventional NIR-I and visible setups [1].

Beyond static structural mapping, Photon etc.’s instruments deliver the rapid temporal resolution necessary to track dynamic hemodynamic events and microvascular dysfunctions in real time. For instance, in physiological models evaluating vascular compromise—such as intermittent hypoxia mimicking sleep apnea [2]—our real-time non-invasive SWIR imaging captures fast functional anomalies. It enables researchers to visualize macromolecular leakage, such as fluorescent dextran extravasation, as it passes through a disrupted blood-brain barrier or altered endothelial walls [2]. The exceptional signal-to-noise ratio provided by our instruments ensures that these subtle, time-sensitive fluorescent variations are accurately quantified from the very first seconds of injection.