Hemodynamic Significance of Middle Cerebral Artery Stenosis Associated With the Severity of Ipsilateral White Matter Changes

Hui Fang; Xinyi Leng; Yuehua Pu; Xinying Zou; Yuesong Pan; Bo Song; Yannie O Y Soo; Thomas W H Leung; Chunxue Wang; Xingquan Zhao; Yilong Wang; Yongjun Wang; Ka Sing Wong; Liping Liu; Yuming Xu; CICAS Study Group

doi:10.3389/fneur.2020.00214

Hemodynamic Significance of Middle Cerebral Artery Stenosis Associated With the Severity of Ipsilateral White Matter Changes

Front Neurol. 2020 Apr 15:11:214. doi: 10.3389/fneur.2020.00214. eCollection 2020.

Authors

Hui Fang¹, Xinyi Leng², Yuehua Pu^{3

4

5

6}, Xinying Zou^{3

4

5

6}, Yuesong Pan^{3

4

5

6}, Bo Song¹, Yannie O Y Soo², Thomas W H Leung², Chunxue Wang^{3

4

5

6}, Xingquan Zhao^{3

4

5

6}, Yilong Wang^{3

4

5

6}, Yongjun Wang^{3

4

5

6}, Ka Sing Wong², Liping Liu^{3

4

5

6}, Yuming Xu¹; CICAS Study Group

Affiliations

¹ Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
² Department of Medicine and Therapeutics, Prince of Wales Hospital, Shatin, Hong Kong.
³ Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
⁴ China National Clinical Research Center for Neurological Diseases, Beijing, China.
⁵ Center of Stroke, Beijing Institute for Brain Disorders, Beijing, China.
⁶ Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease, Beijing, China.

Abstract

Background: Previous studies conflicted in the association between intracranial atherosclerotic stenosis (ICAS) and the severity of white matter changes (WMC). Aims: We aimed to investigate the relationships between the severity of luminal stenosis and the hemodynamic significance of middle cerebral artery (MCA) stenosis, and the severity of ipsilateral WMC. Methods: In this cross-sectional study, patients with a recent ischemic stroke or transient ischemic attack and a 50-99% MCA-M1 stenosis in the Chinese Intracranial Atherosclerosis study cohort were analyzed. The post- to pre-stenotic signal intensity ratio (SIR) was obtained in time-of-flight MR angiography (MRA) to represent the hemodynamic significance of MCA-M1 stenosis, with a lower SIR indicating a hemodynamically more severe lesion. The severity of ipsilesional WMC was assessed by an age-related WMC (ARWMC) scale in T2-weighted fluid attenuated inversion recovery MR imaging. The relationships between the degree of MCA-M1 stenosis, SIR, and ipsilesional ARWMC scale were analyzed. The MCA-M1 lesion with a higher percentage of stenosis was chosen for analyses in patients with bilateral MCA-M1 stenoses. Results: Among 180 subjects (mean age, 64 years), a lower SIR of MCA-M1 stenosis (Spearman correlation coefficient, -0.543; p < 0.001), but not the degree of stenosis (p = 0.93), was significantly linearly correlated with a higher ipsilateral ARWMC. Multivariate ordinal logistic regression identified older age (OR = 1.037; 95% CI, 1.008-1.066; p = 0.011) and lower SIR (OR = 0.010; 95% CI, 0.002-0.058; p < 0.001) as independent predictors for more severe ipsilateral WMC. Conclusion: Patients with hemodynamically more severe ICAS are more likely to have more severe ipsilateral WMC. Longitudinal studies with sequential imaging exams may further reveal the impact of hemodynamic significance of ICAS on the development and progression of WMC.

Keywords: imaging; intracranial atherosclerosis; ischemic stroke; magnetic resonance angiography; white matter changes.