This article reviewed the initial experiences of 73 cases of the magnetic resonance angiography (MRA) to evaluate its usefulness and limitaions as a screening examination. Among them 31 patients underwent correlative contrast angography (CA). MRA
examinations were performed with 3-dimensional time of flight (TOF)acquisitions(carotid, intracranial vessels, abdomen & pelvis), 2-dimensional TOF (abdomen & pelvis), and 3-dimensional phase contrast (PC) method(intracranial vessels, lower
extremity).
In head and neck area, the success rates of MRA in visualization of normal vessels were 91% in the carotid artery and 89% in intracranial vessels. In comparison with correlative CA of 45 lesions in 23 patients, MRA show successful detection of
abnormalities in 43 lesions. There was only one false positive case and one false negative case in differentiation of normal and abnormal cases. Among 43 lesions detected on MRA, 25 lesions were well correlated with CA but 18 lesions showed mild
differences in degree of disease.
In other areas, even thought for a limited number of cases, the abdominal aorta and proximal parts of its major branches were well visualized on MRA. In three cases of renal artery stenosis, MRA showed no visible renal artery in disease side. So
the
abnormality in renal artery could be suspected, but accurate stenotic site could not be detected. In three cases of arterial occlusion in pelvis and lower extremity, MRA were well correlated with CA.
In conclusion, MRA can be used as an ideal safe screening examination method with high success rate and abnormality detection rate, especially in carotid artery, circle of Willis, main intracranial vessels, abdominal aorta and proximal portions
of
its
major branches.
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