Good collateral circulation flow is a promising outcome for ischemic stroke patients. Collateral circulation is the vessels that flow in parallel to each other, perfusing the same target tissue. Different patients are shown to have different statuses of collateral. Good collateral circulation is expected to give significantly better clinical outcomes for stroke patients including acute stroke patients who underwent thrombectomy. Modern multimodal imaging techniques have encouraged neuroradiology to assess collateral flow. This paper presents the basic overview of CBCT technology and compares the usefulness of Cone Beam Computed Tomography (CBCT), Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) based on working principles, performance, cost and applications. In addition, the overview of collateral circulation and its characteristics will be discussed. In assessing collateral circulation, improvement of acquisition techniques and algorithm CBCT provides fast delineation of detail vasculature and improves spatial resolution. It is a three-dimensional (3D) imaging modality to investigate collateral flow. For ischemic stroke patients with clinical symptoms, CBCT improves the image quality for the assessment of collateral circulation in the brain. Precise evaluation of collateral circulation from the images will support the decision-making for suitable acute stroke treatment, benefiting both the patient and doctor.