Multi-Functional In Vivo Cardiovascular Imaging Using Near-Infrared II Fluorescence

Stanford researchers have proposed a novel, in vivo, real-time epifluorescence imaging method in the second near-infrared region using single-walled carbon nanotubes (SWNTs). This method provides both anatomical and hemodynamic information at high spatial and temporal resolutions and in real time. The feasibility of this technology has been demonstrated in animal models, in which small vessel imaging is achieved. Arterial and venous vessels are unambiguously differentiated, and precise quantifications of blood velocity and flow in both normal and ischemic vessels have been determined. This is the first time a 2D surface-weighted, semi-quantitative epifluorescence imaging method achieved high resolution vessel imaging, vessel type differentiation and flow quantification.

Stage of Research:
Successfully demonstrated in animal models. In vivo real-time epifluorescence imaging of mouse hind limb vasculatures in the second near-infrared region (NIR-II) is performed using single-walled carbon nanotubes as fluorophores.
Results show high spatial (?30 ?m) and temporal (200 ms per frame) resolution for small-vessel imaging at 1-3 mm deep in the hind limb owing to the beneficial NIR-II optical window that affords deep anatomical penetration and low scattering.