Label-free photoacoustic microscopy images the concentration of hemoglobin and reveals the vascular anatomy down to single capillaries. The close-up image shows a densely packed capillary bed and individual red blood cells traveling along a capillary.
Spectroscopic photoacoustic microscopy images blood oxygenation (sO2) in a human finger cuticle in vivo. The sO2 map of a capillary loop indicates that most oxygen is unloaded from hemoglobin at the tip of the loop.
Metabolic photoacoustic microscopy measures vessel diameter, total hemoglobin concentration, sO2, tissue volume of interest, and blood flow velocity to compute the metabolic rate of oxygen.
Longitudinal photoacoustic microscopy monitors neovascularization in a transgenic mouse model, identifying three neovascular developmental stages.
Our laboratory combines optics and ultrasound for in vivo high-resolution imaging of anatomical, functional, metabolic, and molecular contrasts at multiple spatial and temporal scales. Our research efforts encompass three main aspects: pushing the technical envelope to cover temporal scales that range from fast cellular dynamics to chronic disease progression, revealing novel optical/acoustic contrast mechanisms to enhance imaging sensitivity and specificity, and bridging the gaps between mechanistic studies in animals and clinical practice in humans.