Time-domain diffuse correlation spectroscopy performance at different source-detector separation

Time domain diffuse correlation spectroscopy (td-DCS), has been proposed as a method that can increase the sensitivity of DCS for detecting blood flow index (BFI) in deep tissue. Several important parameters including the instrument response function (IRF), gate start time, gate width, and source-detector separation (SDS) must be taken into consideration. In our study, we characterized td-DCS system at three different SDS values and assessed each SDS's ability to detect dynamic changes of blood flow caused by moving red blood cells during cuff occlusion.