Prospective adaptive navigator correction for breath‐hold MR coronary angiography

Abstract Current MR coronary angiography (MRCA) methods use breath‐holding to minimize respiratory motion. A major limitation to this technique is misregistration between imaging slices due to breath‐hold variability. Prospective adaptive correction of image location using real‐time navigator measurement of diaphragm position is a potential method for improving slice registration in breath‐hold MRCA. Ten subjects underwent MRCA using an ECG‐gated, fat‐suppressed, segmented k‐space, gradient‐echo sequence. Transverse and coronal images were acquired using standard breath‐holding with and without prospective navigator correction. Breath‐hold MRCA with prospective navigator correction resulted in a 47% reduction in craniocaudal slice registration error compared to standard breath‐holding (0.9 ± 0.2 mm versus 1.7 2 0.4 mm, P = 0.04). Prospective adaptive navigator correction of image location significantly improves slice registration for breath‐hold MRCA and is a promising motion correction technique for cardiac MR.