A novel type of contrast-enhanced magnetic resonance (MR) angiography is highly accurate in identifying blockages in the arteries that carry blood to the brain, according to a study in the February issue of Radiology.
"Contrast-enhanced MR angiography provided highly accurate information about the supra-aortic arteries," said Kambiz Nael, M.D., research fellow and radiology resident at the David Geffen School of Medicine at UCLA in Los Angeles. "MR angiography produced results comparable to the gold standard of digital subtraction angiography (DSA) and multidetector computed tomography (CT) angiography. In addition, this technology produced images with higher resolution over a larger field of view in a shorter amount of time than previous contrast-enhanced MR angiography techniques," he said.
Arterial occlusive disease consists of narrowed or blocked arteries. It commonly affects the supra-aortic arteries, which supply blood to the brain, and is a leading cause of stroke. Currently DSA is the reference standard for evaluating these arteries. However, in 2.5 percent of cases DSA can cause a mini-stroke, and, in rare instances, permanent neurological damage. Therefore, CT and MR angiography are increasingly being used to diagnose arterial occlusive disease. As technology has improved, MR angiography offers advantages over CT, particularly because it delivers no ionizing radiation to the patient.
"MR angiography, using a small quantity of MRI dye injected into a vein in the arm, can produce detailed images of the arteries supplying the brain and can detect even minor degrees of narrowing or blockage. It does not involve exposure to x-rays and is widely regarded as a very safe, painless test," Dr. Nael said.