Abstract 176: The Feasibility of Intravenous Flat-Detector CT (IV FDCT) Angiography for Intracranial Arterial Stenosis

BACKGROUND AND PURPOSE: Intravenous flat-detector CT (IV FDCT) angiography is an emerging technology for the detection of intracranial vascular disease. The study was conducted to determine the feasibility of IV FDCT in estimating major atherosclerotic intracranial arteries stenosis with digital subtraction angiography (DSA) as the reference. METHODS: DSA and IV FDCT were performed simultaneously in patients with transient ischemic attack or acute cerebral infarction. The degree and length of stenosis were measured. The stenotic vessels were categorized into four groups by the grade of stenosis: normal (<30%), mild (30-49%), moderate (50-69%) or severe (>70%). The vessels of the normal group were excluded from analysis to reduce spectrum bias. Measurement of vessels was recorded using an electric ruler by a qualified endovascular neurosurgeon and a neuroradiologist. RESULTS: A total of sixty-nine patients with 842 vessel segments were calculated. Mild (n=56), moderate (n=47) and severe stenosis (n=46) groups were analyzed. IV FDCT had a sensitivity of 97.6%, specificity of 96.9%, and a negative predictive value of 96.9% for detecting ≥50% stenosis and respective values of 91.9%, 98.2%, and 97.4 % for depicting ≥70% stenosis. The difference of stenotic length between two tests was not significantly difference as an increase in the severity of stenosis (Spearman’s rank test; r = - 0.12, p=0.13) CONCLUSION: IV FDCT can be a feasible alternative as a noninvasive method for evaluating stenosis of the major intracranial arteries.

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Abstract 82: Differences Between Caucasians and Asians in Intracranial Arterial Stenosis Among TIA and Minor Stroke Patients: Comparisons of Two Contemporary Cohorts

Stroke ◽

10.1161/str.51.suppl_1.82 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Xinyi Leng ◽

Robert Hurford ◽

Xueyan Feng ◽

Ka Lung Chan ◽

Linxin Li ◽

...

Keyword(s):

Risk Factors ◽

Ct Angiography ◽

Interobserver Agreement ◽

Arterial Stenosis ◽

Minor Stroke ◽

Intracranial Arterial Stenosis ◽

Stroke Patients ◽

Stroke Registry ◽

The Difference ◽

Ischemic Attack

Background: Despite numerous reports indicating ethnic difference in intracranial arterial stenosis (ICAS) between Caucasians and Asians, there has been no direct comparison in disease burden and clinical correlates of ICAS in stroke patients in the two populations with the same criteria to define ICAS. Methods: Acute minor stroke or transient ischemic attack patients who received cerebral MR/CT angiography exam in two cohorts were analyzed: Oxford Vascular Study (OXVASC, 2011-2018) with predominantly Caucasians, and the Chinese University of Hong Kong (CUHK) stroke registry (2011-2015) with predominantly Chinese. ICAS was defined as ≥50% stenosis in any major intracranial artery in MR/CT angiography. Interobserver agreement between 2 investigators for presence of ICAS was assessed in 50 cases with Cohen’s kappa. We compared the burden and risk factors of ICAS in the two cohorts. Results: Overall, 1,287 patients from OXVASC (mean age 69 years) and 640 from the CUHK cohort (mean age 66 years) were analyzed. Interobserver agreement for presence of ICAS was good (kappa=0.82). Prevalence of ICAS was significantly higher in Chinese than in Caucasians: 43.6% in the CUHK cohort versus 20.0% in OXVASC (crude OR 3.10; age-adjusted OR 3.81, 95% CI 3.06-4.75; p<0.001). Mean ages of patients with ICAS in the two cohorts were 75 and 68 years, respectively. The difference between Caucasians and Chinese in ICAS prevalence was smaller in those aged ≥70 years (28.1% versus 51.9%) than those <70 years (9.8% versus 38.0%) (Figure). ICAS shared similar risk factors in the two cohorts, including older age, and history of hypertension and diabetes. Conclusions: Chinese are more susceptible to ICAS, with an earlier onset age than Caucasians, but the ICAS burden in Caucasians was higher than previously estimated, especially in older patients.

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Fluid-Attenuated Inversion Recovery Vascular Hyperintensity in Cerebrovascular Disease: A Review for Radiologists and Clinicians

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.790626 ◽

2021 ◽

Vol 13 ◽

Author(s):

Lichuan Zeng ◽

Jinxin Chen ◽

Huaqiang Liao ◽

Qu Wang ◽

Mingguo Xie ◽

...

Keyword(s):

Cerebrovascular Disease ◽

Cerebrovascular Diseases ◽

Inversion Recovery ◽

Arterial Stenosis ◽

Intracranial Arterial Stenosis ◽

Severe Stenosis ◽

Vessel Occlusion ◽

Retrograde Filling ◽

Fluid Attenuated Inversion Recovery ◽

Ischemic Attack

Neuroradiological methods play important roles in neurology, especially in cerebrovascular diseases. Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is frequently encountered in patients with acute ischemic stroke and significant intracranial arterial stenosis or occlusion. The mechanisms underlying this phenomenon and the clinical implications of FVH have been a matter of debate. FVH is associated with large-vessel occlusion or severe stenosis, as well as impaired hemodynamics. Possible explanations suggested for its appearance include stationary blood and slow antegrade or retrograde filling of the leptomeningeal collateral circulation. However, the prognostic value of the presence of FVH has been controversial. FVH can also be observed in patients with transient ischemic attack (TIA), which may have different pathomechanisms. Its presence can help clinicians to identify patients who have a higher risk of stroke after TIA. In this review article, we aim to describe the mechanism and influencing factors of FVH, as well as its clinical significance in patients with cerebrovascular disease.

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