RESUMO
Background: Effect of stenosis of vertebrobasilar artery (VBA) on cognitive function is elusive. Objective: To investigate association of cerebral hypoperfusion and poor collaterals with vascular cognitive impairment (VCI) in severe VBA stenosis patients. Methods: We consecutively enrolled patients with severe VBA stenosis confirmed by digital subtraction angiography who underwent computed tomographic perfusion (CTP) and cognitive assessments. Patients were divided into poor or good collaterals groups according to the collateral circulation status, and were grouped into different perfusion groups according to CTP. Cognitive function was measured by Montreal Cognitive Assessment (MoCA), Clock Drawing Test, Stroop Color Word Test, Trail Making Test, Digital Span Test, Auditory Verbal Learning Test, and Boston Naming Test scales. The association of cerebral perfusion and collaterals with VCI were explored. Results: Among 88 eligible patients, VCI occurred in 51 (57.9%) patients experienced. Poor collateral was present in 73 (83.0%) patients, and hypoperfusion in 64 (72.7%). Compared with normal perfusion patients, the odds ratio with 95% confidence interval for VCI was 12.5 (3.7-42.4) for overall hypoperfusion, 31.0 (7.1-135.5) for multiple site hypoperfusion, 3.3 (1.0-10.5) for poor collaterals, and 0.1 (0-0.6) for presence of posterior communicating artery (PcoA) compensated for posterior cerebral artery (PCA) and basilar artery (BA). Additionally, decreased scores of cognitive function tests occurred in patients with decompensated perfusion or poor collaterals. Conclusions: Hypoperfusion and poor collaterals were positively associated with cognitive impairment in patients with severe VBA. However, PcoA compensated for the PCA and BA had a protective role in cognitive impairment development.
RESUMO
Background: The recent randomized controlled trials studying intracranial atherosclerotic stenosis (ICAS) have used digital subtraction angiography (DSA) to quantify stenosis and enroll patients. However, some disadvantages of DSA such as invasive features, contrast agent overuse, and X-ray radiation overexposure, were not considered in these studies. This study aimed to explore whether computed tomography angiography (CTA) with semi-automatic analysis could be an alternative method to DSA in quantifying the absolute stenotic degree in clinical trials. Methods: Patients with 50-99% ICAS were consecutively screened, prospectively enrolled, and underwent CTA and DSA between March 2021 and December 2021 at 6 centers. This study was registered at www.chictr.org.cn (ChiCTR2100052925). The absolute stenotic degree of ICAS on CTA with semi-automatic analysis was calculated by several protocols using minimal/maximum/mean diameters of stenosis and reference site from a semi-automatic analysis software. Intraclass correlation coefficient (ICC) was used to evaluate the reliabilities of quantifying stenotic degree on CTA. The optimal protocol for quantifying ICAS on CTA was explored. The agreements of quantifying ICAS in calcified or non-calcified lesions and 50-69% or 70-99% stenosis on CTA and DSA were assessed. Results: A total of 191 participants (58.8±10.7 years; 148 men) with 202 lesions were enrolled. The optimal protocol for quantifying ICAS on CTA was calculated as (1 - the minimal diameter of stenosis/the mean diameter of reference) × 100% for its highest agreement with DSA [ICC, 0.955, 95% confidence interval (CI): 0.944-0.966, P<0.001]. Among the 202 lesions, 80.2% (162/202) exhibited severe stenosis on DSA. The accuracy of CTA in detecting severe ICAS was excellent (sensitivity =95.1%, positive predictive value =98.1%). The agreements between DSA and CTA in non-calcified lesions (ICC, 0.960 vs. 0.849) and severe stenosis (ICC, 0.918 vs. 0.841) were higher than those in calcified lesions and moderate stenosis. Conclusions: CTA with semi-automatic analysis demonstrated an excellent agreement with DSA in quantifying ICAS, making it promising to replace DSA for the measurement of absolute stenotic degree in clinical trials.