CORONARY MRI WITH A RESPIRATORY FEEDBACK MONITOR - THE 2D IMAGING CASE

The inability to return the heart to the same position for all breath- holds during 2D coronary MR imaging can result in imaging different lo cations than desired. This can lead to problems such as (i) missing a whole vessel, or a part of it, (ii) misaligning segments of vessels im aged in different breath-holds, and (iii) degrading image quality when a single slice is acquired in multiple breath-holds. To reduce incons istencies in the breath-hold level, we designed a respiratory feedback monitor (RFM) that uses a bellows to monitor the circumference of the subject's chest. When the circumference of the subject's chest is wit hin preset limits, an audio signal alerts subjects to hold their breat h at that position. Use of the RFM significantly reduces the problems caused by inconsistent breath-holds and the number of breath-holds for an examination in 2D coronary MR imaging.