Magnetic Resonance Angiography and Duplex Scanning Concordance in Detecting Severe Carotid Stenosis.
In this meta-analysis, the authors examine published studies on the consistency (homogeneity) of study outcomes of magnetic resonance angiography (MRA), conventional angiography (XRA), and duplex ultrasound (DU) scanning in assessment of the degree of carotid artery disease.
The sensitivity, specificity, and accuracy of the MRA as a noninvasive diagnostic test are exceptional. Given an adequate two-dimensional time-of-flight (2D-TOF) study, it provides a robust test for the evaluation of carotid stenosis. The authors conclude from this meta-analysis that MRA is at least as accurate as DU in a selected group of patients. The question of superiority for all patients with suspected carotid artery disease is not, however, answered by this meta-analysis. Another question not answered is the question of DU/MRA-XRA concordance/discordance. If DU and MRA were concordant across all, rather than a selected group of patients, would the clinical decision tree be in favor of elimination of XRA? The cost for a DU scan is approximately one third of the cost of an MRA and, from an economic point of view, one could not argue the use of MRA over DU. However, as MRA technology and accuracy improve and when the cost of MRA approaches that of DU, MRA may replace DU as a screening method.
Clearly, a consecutive series of all patients suspected of having carotid artery disease needs to be evaluated by use of the best available diagnostic technologies. A comprehensive protocol would include an evaluation of the sources of difficulties in conducting these tests.
Published In/Presented At
Reed III, J. F., McCullough, S. Wasser, T. (1995). Magnetic Resonance Angiography and Duplex Scanning Concordance in Detecting Severe Carotid Stenosis. Vascular and Endovascular Surgery, 29(3), 177-183.
Medical Sciences | Medicine and Health Sciences | Surgery
Department of Medicine, Department of Surgery