RESPIRATORY COMPENSATION IN MRI CORONARY IMAGING USING DIMINISHING VARIANCE

The effects of complex motion of the heart and surrounding anatomy due to cardiac and respiratory motion is reduced in high resolution imaging of coronary arteries using a diminishing variance algorithm (DVA) using a navigator for tracking heart motion and iteratively reacquiring data frames where a data frame has a positional variance from a cumulative histogram of data. A target position is continually calculated from the cumulative histogram which is smoothed such as by low-pass filtering to continually provide a target position. An image histogram is developed based on a limited number of image frames which are iteratively replaced to attain desired image quality.