Caliber of Intracranial Arteries as a Marker for Cerebral Small Vessel Disease

Abstract

Background: The dilation of intracranial large arteries caliber, may transfer more hemodynamic burden to the downstream brain capillaries, which, in the long run, results in cerebral small vessel disease (CSVD). This study aimed to investigate the relationship between intracranial artery calibers and small vessel disease. Methods: Patients with first-ever ischemic stroke of lacunar infarction subtype were enrolled via Nanjing Stroke Registry Program. An intracranial arterial Z-score, named the brain arterial remodeling (BAR) score, was calculated by averaging the calibers of the seven main intracranial arteries. Among the enrolled patients, those with a BAR score < -1 SD were deemed to have small intracranial artery calibers; those with a BAR score >1 SD were deemed to have large intracranial artery calibers and those with a between BAR score were deemed to have normal intracranial artery calibers. Imaging markers of CSVD, including lacuna, white matter hyperintensity (WMH), enlarged perivascular spaces (EPVS) and cerebral microbleeds (CMBs) were rated and then summed to obtain a total CSVD score. Results: A total of 312 patients were involved in this study, patients with BAR score >1 SD were older (P = 0.039), and more prone to having a history of myocardial infarction (P = 0.033). The Spearman's rank correlation coefficient between the BAR score and total CSVD score is 0.320 (P < 0.001). Binary logistic regression found that BAR score >1 SD was correlated with lacuna (OR = 1.987; 95% CI, 1.037-3.807; P = 0.039); severe WMH (OR = 1.994; 95% CI, 1.003-3.964; P = 0.049); severe EPVS (OR = 2.544; 95% CI, 1.299-4.983; P = 0.006) and CSVD (OR = 2.997; 95% CI 1.182-7.599; P = 0.021). Ordinal logistic regression analysis found that age (OR = 1.028; 95% CI, 1.007-1.049; P = 0.009), hypertension (OR = 3.514; 95% CI, 2.114-5.769; P < 0.001) and BAR score >1 SD (OR = 2.418; 95% CI, 1.350-4.330; P = 0.003) were correlated with the total CSVD score. Conclusions: Patients with large intracranial arterial calibers may have heavier CSVD burden. The mechanisms of this association warrant further study.

Keywords: brain arterial remodeling; cerebral small vessel disease; enlarged perivascular spaces; lacuna infarct; white matter hyperintensity.

Figure 1

Spline regression fit for the proportion of arteries with a negative Z Score for lumen diameter. The diameters of main seven intracranial arteries were measured in the middle cerebral artery (R and L) at the M1 segment [(A), arrow], the basilar artery at the mid-pons [(B), arrow], the intracranial vertebral arteries (R and L) at the V4 segment [(C), arrow], and the internal carotid arteries (R and L) at the intracavernous segment [(B), arrowhead]. (D–F) show the small, middle, and large basilar arteries, respectively (arrow). The BAR score is a construct that discloses the tendency of an individual to have small or large arteries in a single number. As the score decreases, the proportion of arteries with small lumina increases and vice versa (G).