RESPIRATORY BLUR IN 3D CORONARY MR-IMAGING

3D MR imaging of coronary arteries has the potential to provide both h igh resolution and high signal-to-noise ratio, but it is very suscepti ble to respiratory artifacts, especially respiratory blurring. Resolut ion loss caused by respiratory blurring in 3D coronary imaging is anal yzed theoretically and verified experimentally. Under normal respirati on, the width for any Gaussian point spread function is increased to a new value that is at least several millimeters (about 3-4 mm). In viv o studies were performed to compare respiratory pseudo-gated 3D acquis ition with breath-hold 2D acquisition. On average, the overall quality of a pseudo-gated 3D image is worse than that of the corresponding br eath-hold 2D image (P = 0.00). In most cases, respiratory blur caused coronary arteries in pseudo-gated 3D data to have lower resolution tha n in breath-hold 2D data.