The Diagnostic Value of Radial and Carotid Intima Thickness Measured by High-Resolution Ultrasound for Ischemic Stroke

Background: No study has examined intima thickness of the carotid artery and peripheral arteries in subjects with acute ischemic stroke due to large-artery atherosclerosis (LAAS). The aim of this study was to test whether carotid intima thickness (CIT), radial intima thickness (RIT), and dorsalis pedis intima thickness (PIT) are closely associated to atherosclerotic risk factors and whether they possess independent and additive value for differentiating LAAS stroke.

Methods: One hundred and two patients with LAAS stroke and 104 age- and gender-matched control subjects were enrolled. CIT, RIT, and PIT were measured using a 24-MHz, high-resolution ultrasound system. Multivariate linear regression was performed to determine associations between ultrasonic parameters and risk factors. Binary logistic regression was used to evaluate the diagnostic value of different parameters. Receiver operating characteristic curves were plotted to compare the performance of several diagnostic models.

Results: CIT ([36.97 ± 11.27] × 10^-2 vs [23.68 ± 5.12] × 10^-2 mm, P < .001) and RIT ([15.40 ± 3.62] × 10^-2 vs [11.06 ± 2.22] × 10^-2 mm, P < .001) were significantly thicker in patients with LAAS stroke than in control subjects. CIT and RIT were associated with traditional risk factors for atherosclerosis, including age, systolic blood pressure, and serum levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, homocysteine, and glucose. CIT had incremental diagnostic value to traditional risk factors for LAAS stroke (area under the curve, 0.945 vs 0.860; P = .006). The addition of CIT and RIT to traditional risk factors had the best diagnostic performance (area under the curve, 0.961).

Conclusions: Measurement of CIT, RIT, and PIT is feasible and reliable using newly developed ultrasound techniques. CIT and RIT were associated with traditional risk factors for atherosclerosis and exhibited incremental value to traditional risk factors for differentiating patients with LAAS stroke from control subjects.