Three-dimensional phase-sensitive MR angiography with 0.2-T vertical-field MR imaging

The main purpose of this paper is to develop three-dimensional MR angiography for better visualization of blood vessels even with a 0.2-T vertical field MR imaging system, and to evaluate the deductibility of small aneurysms arteriovenous malformations, and stenosis of arteries. We have developed three-dimensional phase-sensitive MR angiography performed by sequence subtraction of rephrasing (velocity-compensated) and dephasing gradient echo. After reconstruction of phase-corrected complex subtraction, MR angiograms were obtained with a ray tracing of the new modified maximum intensity projection at various viewing angles. These images are displayed on a CRT in the cyclic mode to depict the front-rear relation of vessels for recognition