A Fibrous Optofluidic Probe for Endovascular Sensing of Blood Oxygenation and Flow Velocity

Local hemodynamic information including blood oxygenation and flow velocity could guide vascular interventions, yet obtaining these parameters in deep, narrow vessels remains challenging. Here, we report a flexible, submillimeter-scale fibrous optofluidic probe for endovascular sensing of blood oxygenation and flow velocity. The probe integrates a polymer optical fiber for light transmission with a microfluidic tube for dye injection, enabling spectroscopic oximetry and fluorescence dilution-based velocimetry through a single device. Via vascular intervention, we demonstrate local hemodynamic sensing in rabbit arteries and angiography-guided deployment in canine carotid arteries. The probe captures local changes in blood oxygenation and flow velocity during vascular occlusion and reperfusion, revealing hemodynamic disturbances that are not reflected in peripheral monitors. These results illustrate the complementary information provided by local oximetry and velocimetry and establish a compact optofluidic platform for quantitative hemodynamic monitoring during vascular interventions.