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Objectives: Exact characterization and localization of white matter lesions (WMLs) as they relate and contribute to vascular cognitive impairment is highly debated. The purpose of this study was to investigate the impact of WML on cognitive function by using a new anatomy-based classification method., Methods: We detected WML accurately by using a three-dimensional fluid-attenuated inversion recovery (3D FLAIR) imaging technique and subsequently segmented WMLs by using an anatomy-based method. Participants included 56 consecutive patients diagnosed with subcortical vascular cognitive impairment (SubVCI). The volume of WMLs in different anatomic regions was measured. The volume of the hippocampus, the corpus callosum (CC), any lacunar infarcts, total gray matter (GM), and total brain volumes were also calculated., Results: Hippocampal (P  =  0.005) as well as temporal WML volumes (P  =  0.039) were both independently associated with mini-mental state examination (MMSE) score. Only the parietal WML volume (P  =  0.000) was independently associated with Montreal Cognitive Assessment (MoCA) score. Frontal WMLs were independently correlated with executive function. Occipital WMLs were independently associated with visuospatial and recall function. Language impairment was independently correlated with both parietal GM and parietal WML volume. Functions related to orientation were independently associated with parietal WML volume., Discussion: The volume of WMLs in the temporal region as well as in the hippocampus were both independently associated with MMSE score. For the MoCA score, however, only parietal WML volumes were independently correlated. White matter lesions within different anatomic regions were separately correlated with different subdomains of cognitive function.

Objective: We explored the relationship between predicted infarct core, predicted ischemic penumbras and predicted final infarct volumes obtained though apparent diffusion coefficient (ADC)-based method, as well as other clinical variables, and functional outcome., Methods: Patients with acute cerebral ischemic stroke were retrospectively recruited. The National Institutes of Health Stroke Scale score was evaluated at baseline and the modified Rankin Scale (mRS) at day 90. Favorable outcome was defined as an mRS score of 0 to 2, and unfavorable outcome as 3 to 6. Multimodal stroke magnetic resonance imaging was carried out at presentation. The volumes of diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) were measured using the regions of interest (ROI) method. The volumes of predicted infarct core, predicted ischemic penumbra and predicted final infarct were obtained by an automated image analysis system based on baseline ADC maps. The association between baseline magnetic resonance imaging volumes, baseline clinical variables, and functional outcome was statistically analyzed., Results: The study included 30 males and 20 females (mean±SD age, 56±10 years). Baseline DWI, PWI and PWI-DWI mismatch volumes were not correlated with day-90 mRS (P>0.05). Predicted infarct core, predicted ischemic penumbra and predicted final infarct through ADC-based method were all correlated with day-90 mRS (P<0.05). A better outcome was associated with a smaller predicted volume. Low baseline National Institutes of Health Stroke Scale and recanalization also demonstrated a trend toward a favorable outcome. Receiver operating characteristic analysis showed that the area under the curve of predicted final infarct volume and recanalization were higher with statistical significance (P<0.001)., Discussion: Predicted volumes obtained from ADC-based methods, especially predicted final infarct volume, as well as baseline National Institutes of Health Stroke Scale and recanalization may have effect on functional outcome in acute ischemic stroke.

Computed tomography perfusion (CTP) map can sensitively and accurately distinguish between infarct core and ischemic penumbra. However, CTP mapping software might not generate a perfusion map because of head movement; thus, analysing CTP source images (CTP-SI) is necessary in this situation to provide information for stroke diagnosis and therapy. In our work, 'one-stop shop' computed tomography (CT) examination including non-contrast-enhanced CT (NCCT), CTP, CT angiography (CTA) were performed in 24 patients with symptoms of acute stroke less than 9 hours. We divided patients into two groups (with and without delayed perfusion on CTP-SI), and compared the Alberta Stroke Program Early CT Score (ASPECTS) on CTP-SI and CTA-SI with follow-up imaging. Using follow-up imaging ASPECTS as the final infarct size, our results suggests that the ASPECTS of both CTP-SI and CTA-SI effectively predict final infarct core in the group without delayed perfusion, whereas CTP-SI has a potential advantage over CTA-SI in being able to predict final infarct core in the group with delayed perfusion. In conclusion, CTP-SI provides useful complementary information when CTP map software could not generate perfusion maps.

Objective: The purpose of this study was to develop a methodology on computed tomography (CT) perfusion source images for an acute ischemic stroke in predicting infarct core and penumbra., Methods: Computed tomography examinations, including non-contrast enhanced CT, CT perfusion and CT angiography, were performed on 24 patients with symptoms of stroke in less than 9 hours. The Alberta Stroke Program Early CT Score (ASPECTS) was analysed on arterial and venous phase CT perfusion source images and then compared with the ASPECTS on follow-up imaging for an efficacy assessment., Results: The ASPECTS on arterial phase CT perfusion source images was significantly different from venous phase CT perfusion source images (z=-2.812, p=0.005); linear regression analysis revealed that there was a statistically significant relationship between venous phase CT perfusion source images and the follow-up imaging (beta=0.715, p=0.003)., Conclusion: The limited data suggested that CT perfusion source images of both arterial and venous phases may have the potential of being used as an assessment for infarct core and penumbra in acute ischemic stroke.

Objective: We investigated whether baseline vessel status evaluated by magnetic resonance angiography (MRA) can be the foremost factor to classify acute ischemic stroke patients into subgroups for thrombolytic therapy within 3-6 hours of symptom onset., Methods: Acute ischemic stroke patients beyond 3 hours after symptom onset were examined by stroke magnetic resonance imaging (MRI) (diffusion- and perfusion-weighted imaging, and MRA) before and after thrombolysis treatment within 24-48 hours. Stroke MRI was used to classify acute ischemic stroke patients into subgroups and select optimal patients for thrombolytic treatment. Clinical scores were compared to determine whether there were significant differences among subgroups., Results: The difference in day 90 modified Rankin scale (mRS) between treated salvageable and untreated salvageable patients with recombinant tissue plasminogen activator (rt-PA) was remarkably statistically significant (p=0.02). Treated salvageable patients had more favorable clinical outcomes as compared with the untreated salvageable patients. Patients who did not have baseline artery occlusion were associated with more favorable clinical outcomes than untreated salvageable patients (p<0.001). The difference between treated salvageable and patients without artery occlusion in 90 day mRS score was not statistically significant (p=0.058)., Conclusion: Baseline vessel status evaluated by MRA may be used as the first factor ahead of mismatch to categorize acute ischemic stroke patients into subgroups. Patients who do not have initial vessel occlusion may not need thrombolytic therapy.