Visualization of Time-to-Peak Changes on Cerebral Digital Subtraction Angiography for Patients Underwent Endovascular Therapy

Cerebral digital subtraction angiography (DSA) image series are routinely used for treating cerebral arterial stenosis or occlusion. The time-to-peak value is an important hemodynamic parameter for treatment planning and prognosis assessment. The endovascular therapy is a standard procedure to treat stenotic vessels. This study aims to provide a technique to evaluate the change in TTP achieved by the treatment. A registration process is applied to the two time-to-peak images of two DSA dataset acquired from the same patient, before and after the endovascular therapy. The change of TTP can be precisely calculated from the registered TTP images for every pixel. The TTP-difference image displays the hemodynamic improvement achieved by the treatment procedure. This image can assist the physicians to evaluate the effectiveness of the treatment visually and quantitatively.