Method for pixel shift calculation in digital subtraction angiography and X-ray diagnostic imaging system for generating images in digital subtraction angiography

摘要

An X-ray diagnostic imaging system for generating images in digital subtraction angiography is proposed. A mask image frame of a patient and a series of live image frames of the patient acquired in the same imaging position of the mask frame acquisition are accessed. One of the mask and the live image frames is contrast-enhanced. Possible shift vectors in a region of interest are assumed being a difference vector between the mask and a respective live image frame and a scoring is calculated. Possible shift vector with the highest scoring is chosen as an elected shift vector. A likelihood representing a quality value of the elected shift vector is calculated. The mask image frame is shifted with respect to the respective live image frame by a modified shift vector depending on the likelihood. The shifted mask image frame is subtracted from the respective live image frame and is displayed.