Volumetric Distribution of the White Matter Hyper-Intensities in Subject with Mild to Severe Carotid Artery Stenosis: Does the Side Play a Role?

Purpose: The purpose of this paper was to assess the difference in the distribution of white matter hyperintensities (WMHs) on left and right sides of the brain hemispheres of subjects with mild to severe carotid artery stenosis. Material and Methods: Eighty consecutive patients (mean age 71 +/- 6 years, males 66) with carotid artery stenosis were prospectively recruited. FLAIR-WMH lesion volume was performed using a semiautomated segmentation technique (Jim, Xinapse System, Leicester, UK). The Wilcoxon test was applied to verify the differences in the volume of WMHs between the right and left hemispheres. Results: A statistically significant difference was found in the middle cerebral artery (MCA) territory for the volume of the lesions (median volume of WMHs of the left side = 889.5 mm(3); median volume of WMHs on the right side = 580.5 mm(3); P = .0416); no statistically significant difference was found on the other territories by taking into considerations the lesions. By analyzing the degree of stenosis, we found a higher degree of stenosis of the left side (67.9%; 95% confidence interval [CI], 64.8%-70.9%) compared with the right side (65.7%; 95% CI, 62.4%-68.9%), but the Mann-Whitney test did not show a statistically significant difference (P = .3235). Conclusions: Results of our study suggest that there is a difference in the distribution of WMHs in the brain hemispheres according to the left/right side on the MCA territories and for the periventricular white matter in subjects with mild to severe carotid artery stenosis.