In recent years, it has been shown that it is possible to achieve time-resolved cone-beam CT imaging using a Carm cone-beam CT system equipped with a back-and-forth multi-sweep data acquisition mode. A reconstruction algorithm which has been referred to as SMART-RECON has demonstrated to achieve better than 1.0 frame per second (fps) temporal resolution. Recently, another innovation was introduced into SMART-RECON to achieve 7.5 fps, this innovation opens up a whole new opportunity to extract other physiological information besides the well-known cone-beam CT perfusion. In this work, we study the feasibility to obtain quantitative blood flow information from high temporal resolution time-resolved cone beam CT angiography. This new possibility would enable physicians to more accurately pinpoint occlusion sites and provide the needed image guidance to plan for endovascular therapy in acute ischemic stroke patients as an example. Numerical simulations with ground truth and preliminary clinical case studies have been conducted to demonstrate the feasibility of blood flow quantification from time-resolved CBCT angiography.