Abstract
Advantages and disadvantages of multiple MR angiographic sequences were investigated in 8 patients. Artifacts present on time of flight (TOF) images were due to substances with short T1, hemosiderin, surgical clips and fats. Phase contrast (PC) angiography allowed velocity resolution of vascular lesions and flow direction and had excellent background suppression. Gadopentetate dimeglumine enhancement increased the visualization of the vascular structures on both TOF and PC images. Two-dimensional (2D) TOF images were useful in slow flow such as dilated vessels and draining veins from AVMs. Three-dimensional (3D) TOF images were excellent in depicting small AVMs. Large AVMs were selected in the 2D TOF or 2D PC technique. AVMs with hematoma or surgical clips, and marked elevated flow had to be examined by 3D PC with the compatible velocity encoding provided with 2D PC. 2D PC images were useful in the assessment of the patency of major vascular structures.
