We present fast functional optical-resolution photoacoustic microscopy (OR-PAM) that can simultaneously image hemoglobin concentration, blood flow speed, and oxygen saturation with three-pulse excitation. To instantaneously determine the blood flow speed, dual-pulse photoacoustic flowmetry is developed to determine the blood flow speed from photoacoustic signal decay in sub-microseconds. Grueneisen relaxation effect is compensated for in the oxygen saturation calculation. The blood flow imaging is validated in phantom and in vivo experiments. The results show that the flow speed can be measured accurately in sub-microseconds by comparing the dual-pulse flowmetric method with photoacoustic Doppler flowmetry. Wide-field OR-PAM of hemoglobin concentration, blood flow speed, and oxygen saturation are demonstrated in the mouse ear. This technical advance enables more biomedical applications for fast functional OR-PAM.

我们介绍了快速功能光学分辨率光声显微镜（OR-PAM），它可以同时通过三脉冲激发成像血红蛋白浓度，血流速度和血氧饱和度。为了瞬时确定血流速度，开发了双脉冲光声流量计，以从亚微秒内的光声信号衰减确定血流速度。在氧饱和度计算中会补偿Grueneisen松弛效应。血流成像已在幻像和体内实验中得到验证。结果表明，通过将双脉冲流量计方法与光声多普勒流量计方法进行比较，可以在亚微秒内准确测量流速。血红蛋白浓度，血流速度和血氧饱和度的广域OR-PAM在小鼠耳朵中得到证实。