Efficacy of screening MR angiography and Doppler ultrasonography in the evaluation of carotid artery stenosis.
Significant progress has been made in the development of noninvasive screening techniques for evaluation of the carotid bifurcation prior to contrast angiography. The role and significance of Magnetic Resonance Angiography (MRA) as an efficient cost effective screening examination for carotid artery stenosis remains to be determined. To that end, 120 carotid vessels, in 60 consecutive patients with carotid artery disease, were studied using MRA, Duplex ultrasonography (U/S), and conventional Digital Subtraction Arteriography (DSA). In a prospective blinded manner, using a standard scoring schematic, each carotid artery was evaluated with regard to degree of stenosis, zone of stenosis, and quality of the screening examination. The efficacy of MRA and U/S for detection of extracranial carotid stenoses was correlated with conventional DSA, which was used as a "standard of reference" for each patient. Screening studies were considered positive if the vessel stenosis was determined to be greater than 40 per cent. As a screening examination, U/S yielded a sensitivity of 88 per cent and a specificity of 81 per cent with 11 false positive and 7 false negative studies. MRA yielded a sensitivity of 84 per cent and a specificity of 81 per cent with 11 false positive and 9 false negative studies. Range of cost of each imaging modality was surveyed from our region as well as ease of access to each modality. MRA and U/S achieved equivalent accuracy as screening examinations and correlated well in sensitivity and specificity when quality of the examination and experience of the examination center was taken into consideration.(ABSTRACT TRUNCATED AT 250 WORDS)
White
J E
JE
Department of Surgery, University of Tennessee College of Medicine, Chattanooga 37403.
Russell
W L
WL
Greer
M S
MS
Whittle
M T
MT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods; D001157:Arterial Occlusive Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging; D016477:Artifacts; D002340:Carotid Artery Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D016893:Carotid Stenosis / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D014463:Ultrasonography