Carotid artery calcification on CT may independently predict stroke risk.
OBJECTIVE
The purpose of our study was to quantitatively evaluate calcified atherosclerotic burden in the cervical carotid arteries using MDCT to determine the relationship of scores with luminal stenosis and symptomatology.


METHODS
Calcium plaque volume was measured in 106 cervical carotid arteries (53 patients) using MDCT angiography. The study group included 32 asymptomatic patients (mean age, 70.2 +/- 8.7 [SD] years; 15 women, 17 men) and 21 patients with ischemic neurologic symptoms (69.6 +/- 12.9 years; eight women, 13 men). By vessel, there were 43 high-grade stenotic (> or = 60% by North American Symptomatic Carotid Endarterectomy Trial [NASCET] criteria), 15 moderate-grade stenotic (30-59%), and 44 mild-grade stenotic or normal (0-29%) vessels, with four excluded for prior carotid endarterectomy. Volume scores were calculated by summing the area of calcium in the common and extracranial internal carotid arteries on axial slices and multiplying by the slice increment.


RESULTS
Controlling for cardiovascular risk factors and luminal stenosis, we found that scores were significantly related to the occurrence of symptoms (p = 0.003). Even with patient age as a covariant, patients with high-grade stenosis had significantly higher scores than those without high-grade disease (p = 0.004). Moreover, quantitative burden was associated with luminal stenosis on adjusted multivariate analysis (p = 0.034). The specificity and positive predictive value for high-grade luminal narrowing were notably lower on individual vessel analysis than on total score analysis, likely secondary to variability in vascular remodeling.


CONCLUSIONS
Calcium scores in the cervical carotid arteries may represent an independent marker for luminal stenosis and ischemic symptoms. A prospective longitudinal study examining calcium levels and morbidity may be warranted to examine whether burden has a role in risk stratification.
Nandalur
Kiran R
KR
Department of Radiology, University of Virginia, PO Box 800170, Charlottesville, VA 22908, USA. krn2d@virginia.edu
Baskurt
Erol
E
Hagspiel
Klaus D
KD
Finch
Michael
M
Phillips
C Douglas
CD
Bollampally
Sirisha R
SR
Kramer
Christopher M
CM
D000368:Aged; D002114:Calcinosis / Q000150:complications / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000209:etiology; D014057:Tomography, X-Ray Computed / Q000379:methods*