RESUMO
Background: Limited information exists regarding susceptibility vessel sign (SVS) found beyond 24 hours after stroke onset. This study aimed to compare the presence and quantitative measurements of SVS between the large artery arteriosclerosis (LAA) subtype and the cardioembolism (CE) subtype in patients with subacute stroke. Methods: We retrospectively analyzed stroke survivors with the LAA subtype or the CE subtype who had occlusion or severe stenosis of the responsible intracranial large vessel and who had undergone susceptibility-weighted imaging (SWI) between day 3 and day 14 after stroke onset at Peking University First Hospital from December 2017 to January 2022. Independent reviewers evaluated the presence, location, length, and diameter of SVS. Multivariable logistic regression analysis was used to analyze the relationship between the presence of SVS and stroke subtype. Results: Among 173 stroke survivors, including 133 with the LAA subtype and 40 with the CE subtype, SVS was found in 95 patients. The presence of SVS was higher in the LAA group than in the CE group (59.4% vs. 40.0%; P=0.031), and this difference remained statistically significant in multivariable analysis [odds ratio (OR) =2.199; 95% confidence interval (CI): 1.019-4.745; P=0.045]. The LAA group had a longer SVS than did the CE group (20.7±10.6 vs. 13.8±5.1 mm; P<0.001). Conclusions: In patients with subacute ischemic stroke caused by intracranial large vessel occlusion (LVO) or severe stenosis, the LAA group had a higher incidence and a longer SVS than did the CE group. This suggests that SVS may have potential value in the etiology diagnosis of patients with subacute stroke.
RESUMO
BACKGROUND: Recently it has been proposed that microglial response has a stage-dependent effect on the progression of Alzheimer's disease (AD). Cerebrospinal fluid (CSF) sTREM2 has emerged as a promising microglial activation marker. OBJECTIVE: To test the stage-dependent role of microglia by studying the association between baseline sTREM2 and dynamic brain structural changes in AD and mild cognitive impairment (MCI) patients. METHODS: 22 amyloid-ß-positive (A+) and tau-positive (T+) AD and 24 A+T+MCI patients were identified from the Alzheimer's Disease Neuroimaging Initiative. The patients had baseline CSF amyloid-ß, phosphorylated-tau, and sTREM2, and were followed up for at least one year by T1-weighted and diffusion tensor imaging scans. Gray matter volumes and white matter microstructural integrity were evaluated. Linear mixed models were applied to analyze how baseline sTREM2 may influence the rate of brain structural changes while adjusting for the effects of age, APOE4 status, and the CSF core markers. RESULTS: In A+T+AD patients, baseline CSF sTREM2 was associated with faster mean diffusivity increase in the bilateral posterior corona radiata and right superior longitudinal fasciculus. In A+T+MCI patients, baseline CSF sTREM2 was associated slower gray matter volumetric loss in parahippocampal gyrus, left fusiform cortex, left middle temporal gyrus, and left lateral occipital cortex. Baseline CSF sTREM2 also had a protective effect against mean diffusivity increase in right inferior fronto-occipital fasciculus, left superior longitudinal fasciculus, left forceps minor, and left uncinate fasciculus. CONCLUSION: Microglial activation at early stage might have a protective effect against neurodegeneration, while at late stage it might facilitate AD. Future efforts on modulating microglial activation could be promising, given a carefully selected time window for intervention.