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Background and Purpose— Posterior circulation ischemic stroke (IS) is generally considered an illness with a poor prognosis. However, there are no effective rating scales to predict recurrent stroke following it. Therefore, our aim was to identify clinical or radiological measures that could assist in predicting recurrent cerebral ischemic episodes. Methods— We prospectively enrolled 723 noncardiogenic posterior circulation IS patients with onset of symptoms Results— A total of 40 patients (5.5%) had recurrent IS or TIA within 1 year of posterior circulation IS. Multivariate Cox regression identified chief complaint with dysphagia (hazard ratio [HR], 4.16; 95% confidence interval [CI], 1.69–10.2; P =0.002), repeated TIAs within 3 months before the stroke (HR, 15.4; 95% CI, 5.55–42.5; P P =0.05), multisector infarcts (HR, 5.38; 95% CI, 1.25–23.3; P =0.02), and not on antithrombotics treatment at discharge (HR, 3.06; 95% CI, 1.09–8.58; P =0.03) as independent predictors of recurrent IS or TIA. Conclusions— Some posterior circulation IS patients are at higher risk for recurrent IS or TIA. Urgent assessment and preventive treatment should be offered to these patients as soon as possible.

Background and Purpose— High signal on T1-weighted fat-suppressed images in middle cerebral artery plaques on ex vivo magnetic resonance imaging was verified to be intraplaque hemorrhage histologically. However, the underlying plaque component of low signal on T1-weighted fat-suppressed images (LST1) has never been explored. Based on our experience, we hypothesized that LST1 might indicate the presence of lipid core within intracranial plaques. Methods— 1.5 T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of bilateral middle cerebral arteries. Then middle cerebral artery specimens were removed for histology processing. LST1 presence was identified on magnetic resonance images, and lipid core areas were measured on the corresponding histology sections. Results— Total 76 middle cerebral artery locations were included for analysis. LST1 showed a high specificity (96.9%; 95% confidence interval, 82.0%–99.8%) but a low sensitivity (38.6%; 95% confidence interval, 24.7%–54.5%) for detecting lipid core of all areas. However, the sensitivity increased markedly (81.2%; 95% confidence interval, 53.7%–95.0%) when only lipid cores of area ≥0.80 mm 2 were included. Mean lipid core area was 5× larger in those with presence of LST1 than in those without (1.63±1.18 mm 2 versus 0.32±0.31 mm 2 ; P =0.003). Conclusions— LST1 is a promising imaging biomarker of identifying intraplaque lipid core, which may be useful to distinguish intracranial atherosclerotic disease from other intracranial vasculopathies and to assess plaque vulnerability for risk stratification of patients with intracranial atherosclerotic disease. In vivo clinical studies are required to explore the correlation between LST1 and clinical outcomes of patients with intracranial atherosclerotic disease.

Background and Objectives: External counterpulsation (ECP) is a non-invasive method used to augment cerebral blood flow of patients with ischaemic stroke via induced hypertension. We aimed to investigate whether the cerebral augmentation index (CAI) evaluated by ECP can predict clinical outcomes after acute ischemic stroke. Methods: We enrolled acute ischemic stroke patients within 7 days after stroke onset. Bilateral middle cerebral arteries of patients were monitored using transcranial Doppler (TCD). Flow velocity changes before, during and after ECP were, respectively, recorded for 3 mins. The cerebral augmentation index (CAI) was the increase in percentage of the middle cerebral artery mean flow velocity during ECP compared with baseline. TCD data were analysed based on the side ipsilateral or contralateral to the infarct. The modified Rankin Scale (mRS) (good outcome: mRS 0∼2; poor outcome: mRS 3∼6) was evaluated 3 months after the index stroke. Results: 200 patients were included (mean age, 64.5±8.9 years; 86.5% males). At month 3 after stroke onset, univariate analysis showed that the National Institutes of Health Stroke Scale at recruitment was significantly higher in the poor outcome group, while the bilateral CAIs were significantly lower in the good outcome group than those in the poor outcome group (ipsilateral 3.72±2.94 vs 7.92±6.25, p=0.032; contralateral 4.04±3.82 vs 6.98±6.05, p=0.048). Multivariate logistic regression showed that bilateral CAIs were independently correlated with an unfavorable functional outcome after adjusting for confounding factors. Conclusions: The higher degree of cerebral blood flow velocity augmentation on the both sides ipsilateral and contralateral to the infarct induced by ECP is independently correlated with an unfavorable functional outcome after acute ischemic stroke.

Background and Purpose— Clinical trial studies show that plaque eccentricity (symmetry) is among the plaque features that have been associated with more frequent cerebrovascular events. Plaque eccentricity of intracranial atherosclerotic disease is unclear because of lacking of cerebral artery specimens. Methods— 1.5T magnetic resonance imaging was performed in the postmortem brains to scan the cross sections of middle cerebral artery. Plaque eccentricity of histology-verified middle cerebral artery atherosclerosis was calculated on T1-weighted fat-suppressed sequence. Results— Validated by histology, concentric atherosclerotic plaques were identified in 46 middle cerebral arteries (63.9%) on magnetic resonance imaging and eccentric plaques in 26 arteries (26.1%). Eccentric plaques showed higher maximum wall thickness and lower minimum wall thickness than concentric plaques (both P Conclusions— Intracranial atherosclerosis presents as eccentric or concentric in geometry, which may be not linked to intracranial plaque risk. Further in vivo imaging studies are needed to identify morphological features of intracranial plaques and to verify its association with brain infarctions.

Background and Purpose: Vasa vasorum, which constitutes a network of microvasculature, plays a nutritive and drainable role in vessel walls of arteries. The existence of vasa vasorum within brain vasculature is rarely reported. Based on a series of cerebral artery specimens, we aimed to describe the distribution features of vasa vasorum among intracranial arteries, including middle cerebral arteries (MCAs), basilar arteries (BAs) and vertebral arteries (VAs) and potential effects of vasa vasorum on atherosclerosis morphology. Methods: One hundred and fifty- seven arteries (64 MCAs, 32 Bas and 61 VAs) were obtained from consecutively recruited 32 autopsy cases aged 45 years or above. Routine histology and immunostaining processing were performed to identify the presence of adventitial vasa vasorum and to study the phenotypes and specific components of intracranial atherosclerotic lesions. Results: Among 157 intracranial cerebral arteries, adventitial vasa vasorum were present most frequently in the vertebral arteries (77%), followed by basilar arteries (44%) and middle cerebral arteries (20%). Arteries with adventitial vasa vasorum had greater thickness of tunica adventitia (0.10±0.06 mm vs. 0.06±0.03 mm, p &lt 0.001) and larger size in diameters (3.41± 0.73 mm vs. 2.97± 0.66 mm, p &lt 0.001). The occurrence of adventitial vasa vasorum correlated with high frequency of complicated plaques and higher rate of concentric atherosclerotic lesions (70% vs. 36%, p &lt 0.001). Conclusion: For the first time, our study demonstrated the presence of adventitial vasa vasorum within brain vasculature, especially at vertebral arteries. The correlations between adventitial vasa vasorum and intraplaque hemorrhage, inflammation and calcification suggest that adventitial vasa vasorum may serve as a predictor of unstable atherosclerotic lesions. Further studies are required to explore the biological behavior of adventitial vasa vasorum within cerebral arteries.

Introduction: Intracranial arterial calcification (IAC) is frequently observed on brain computed tomography (CT) in stroke patients. However, the association between IAC and stroke recurrence after hospital discharge has received little attention. In this study, we aim to explore the effect of IAC on the long-term stroke recurrence. Subjects and methods: We prospectively recruited consecutive patients with ischemic stroke or transient ischemic attack during December 2004 and March 2005 from a population-based stroke registry at Prince of Wales Hospital. Demographic characteristics, stroke risk factors, and stroke etiology were recorded at baseline. IAC volume and IAC Agatston score were both measured on 16-slice CT with a semi-automatic system. All patients were regularly followed up for stroke recurrence till July 2016. Results: Total 694 patients (age 71.6±12.4; male sex 50.3%; median follow-up period 8.8 years) were followed up. Stroke recurred in 156 patients (22.5%). Multivariate Cox proportional hazard model found higher IAC Agatston score was predictive factor for both recurrent stroke (HR per 1-SD increment 1.301; 95% CI, 1.084-1.561, p =0.005) and stroke death (HR per 1-SD increment, 1.441; 95% CI, 1.061-1.956, p =0.019). In addition, among different stroke etiological subtypes, IAC Agatston score was independent risk factor of stroke recurrence for index small-vessel occlusive stroke patients (HR per 1-SD increment, 1.674; 95% CI, 1.061-2.639, p =0.027). Conclusions: Quantitative-evaluated IAC scores can predict long-term stroke recurrence and stroke death.

Background and Purpose— Cerebral microbleeds (CMBs) are common in stroke survivors and community-dwelling elderly. The clinical significance of CMBs in the outcome of poststroke depression (PSD) is unknown. This study examined the association between the 1-year outcome of PSD and CMBs. Methods— The study population comprised 774 Chinese patients with acute ischemic stroke who were admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong. Three and 15 months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a Geriatric Depression Scale score of ≥7. Of the 213 patients with PSD at the 3-month follow-up, 135 (63.4%) attended the 15-month follow-up, at which time 89 (65.9%) patients remained depressed (nonremitters), and 46 (34.1%) had recovered (remitters). The presence and location of CMBs were evaluated with magnetic resonance imaging. Results— In comparison with the remitters, nonremitters were more likely to have lobar CMBs (18.4% versus 4.3%; P =0.024). Lobar CMBs remained an independent predictor of PSD in the multivariate analysis, with an odds ratio of 4.96 ( P =0.039). Conclusions— The results suggest that lobar CMBs may influence the outcome of PSD. The importance of CMBs in the clinical course of depression in stroke survivors warrants further investigation.

Background and Purpose— Geographic variation and sex difference in the distribution of intracranial atherosclerosis (ICAS) have not been fully discussed before in Chinese patients with cerebral ischemia. We performed this study with the aim to investigate geographic and sex difference in the distribution of ICAS in China. Methods— In this prospective multicenter study, we evaluated 2864 consecutive patients who experienced an acute cerebral ischemia within 7 days of symptom onset in 22 hospitals in China. All the inclusive patients underwent 3-dimensional time-of-flight MR angiography and duplex color Doppler ultrasound or contrast-enhanced MR angiography to document the presence of intracranial or extracranial stenosis. Intracranial large-artery atherosclerosis was defined as ≥50% diameter reduction on MR angiography. Results— The proportion of patients with ICAS was significantly higher in north China than in south China (50.22% versus 41.88%; P 63 years, the percentage of ICAS in women was notably higher than in men (51.51% versus 45.40%; P =0.028). In elderly patients, women had higher proportion of diabetes mellitus, hypertension, hyperlipidemia, and heart disease than men. Conclusions— There exists geographic and sex difference in the distribution of symptomatic ICAS in China. Public health measures should strengthen improving social determinants of health and risk factor prevention/control in high-risk populations for decreasing stroke risk.

Background and Purpose— Large artery intracranial occlusive disease (LAICOD) is a predominant cause of ischemic stroke in China. Carotid intima-media thickness (CIMT) and presence of carotid plaque are also related to subsequent ischemic stroke. However, the correlation between these and LAICOD is less clear. Methods— This was a community-based cross-sectional study. All subjects underwent carotid duplex ultrasonography and transcranial Doppler. Mean CIMT value of bilateral common carotid arteries was used. Plaque was defined as a focal CIMT of >1.5 mm. LAICOD in transcranial Doppler was defined by peak systolic velocity and age, and presence of turbulence or musical sound was also considered. Results— For the 537 subjects studied (mean age, 54.7±10.1 years; 46.9% males), mean CIMT was 0.74±0.12 mm, with the 75th percentile of 0.80 mm. CIMT ≥1.0 mm was identified in 13 subjects (2.4%). Plaques were detected in 79 subjects (14.7%). Compared with those without LAICOD, the 48 subjects (8.9%) with LAICOD had greater CIMTs (0.77±0.09 versus 0.73±0.12 mm; P =0.044), more with CIMT of higher quartiles ( P =0.007), and more with carotid plaques (25.0% versus 13.7%; P =0.035). However, after adjusting for confounding factors, CIMT and presence of carotid plaque were not significantly associated with LAICOD. Conclusions— The results suggest that CIMT and presence of carotid plaque probably are not independently correlated with LAICOD in Chinese community residents, which supported the existence of pathologic and pathophysiologic differences in atherogenesis of intra- and extracranial arteries.

Background and Purpose— Cerebral microbleeds (CMB) are common in stroke survivors and the community-dwelling elderly. The clinical significance of CMB in the development of depression after a stroke is unknown. This study examined the association between poststroke depression (PSD) and CMB. Methods— A cohort of 235 patients with acute lacunar stroke admitted to the stroke unit of a university-affiliated regional hospital in Hong Kong was recruited. Three months after the onset of the index stroke, a research assistant administered the locally validated 15-item Geriatric Depression Scale. PSD was defined as a Genetic Depression Scale score of ≥7. The presence and location of CMB were evaluated with MRI. Results— In comparison with the non-PSD group, PSD patients were more likely to have lobar CMB (33.3% versus 19.9%; P =0.022). Lobar CMB remained an independent predictor of PSD in the multivariate analysis, with an odds ratio of 2.08 ( P =0.032). Conclusions— The results suggest that lobar CMB may play a role in the development of PSD. The importance of CMB in the pathogenesis of depression in stroke survivors and the general elderly population warrants further investigation.

Background: The association between protein S deficiency (PSD) and ischemic stroke is controversial and warrants further investigation. Methods: We conducted a genotype and MRI correlation study in a Chinese family in which hereditary PSD cosegregated with premature ischemic strokes. Six out of 11 family members inherited PSD type III in an autosomal dominant manner. Results: Among all PSD members, a novel missense mutation 1063C→T in exon 10 of protein S alpha ( PROS1 ) was identified, which encoded a substitution of arginine to cysteine at position 355 (R355C) in the first globular domain of laminin A of protein S. Wild-type PROS1 sequences were retained in non-PSD members. MRI detected deep white matter infarctions predominantly distributed in the borderzone regions. The infarct topography was homogeneous in all adult mutant carriers. By contrast, cerebral infarction was absent in nonmutant carriers. Extensive investigation in the family did not reveal any confounding stroke risk. Haplotype analysis with high-density single nucleotide polymorphism markers revealed a 6.1-Mb minimally rearranged region (rs12494685 to rs1598240) in 3q11.2, lod = 3.0. Among the 7 annotated genes in this region, PROS1 is known to be associated with thrombotic disorders. MRI screening in an additional 10 PSD families without R355C showed no cerebral infarction. Conclusions: PROS1 R355C mutation cosegregated with PSD type III and premature white matter infarctions in the index family. The findings substantiate an association between PSD and stroke. Study of the mechanism underlying this association may improve our understanding of premature cryptogenic white matter infarction.

The objective of this cross-sectional study was to identify the factors associated with health-related quality of life (HRQOL) of family caregivers of Chinese stroke patients. One hundred and twenty-three stroke patients consecutively admitted to a stroke clinic and their 123 family caregivers were recruited. The caregivers' HRQOLs were assessed with the Short Form 36 (SF-36). Two subscores of the SF-36, the Physical Component Summary and the Mental Component Summary Scores served as the dependent variables. Independent variables comprised patients and caregivers' demographic data and physical and psychological conditions in relation to caregivers' HRQOL. The severity of coexisting illnesses of both the patients and their caregivers was assessed using the Cumulative Illness Rating Scale. The Geriatric Depression Scale (GDS) was administered to rate both the patients and their caregivers' depressive symptoms. The extent of the patients' functional disability was assessed using the Barthel Index and the Instrumental Activities of Daily Living. Global cognition of the patients was measured using the Mini Mental State Examination. The level of social support and recent life events of the caregivers were rated using Lubben Social Network Scale and the Modified Life Event Scale, respectively. The multiple linear regression revealed caregivers' Cumulative Illness Rating Scale and GDS score were associated with Physical Component Summary Score of SF-36. The patients and caregivers' GDS score were associated with Mental Component Summary Score of SF-36. Severity of depressive symptoms in Chinese stroke patients and their caregivers is an important factor associated with the caregivers' HRQOL. Further studies evaluating interventions on caregivers' HRQOL should include the assessment and management of mood disorders.

Introduction: In SAMMPRIS, the benefit of aggressive medical therapy over stenting persisted throughout the extended follow-up. It is uncertain how modern medical management could diminish stroke relapses. Method: In a prospective academic-initiated study, we recruited 40 patients (mean age 63.4±9.0 years) with acute strokes attributed to high-grade (≥70%) intracranial atherosclerotic stenosis for 3D-rotational angiograms before and after intensive medical therapy for 12 months. Treatment targets included low-density lipoprotein Results: Overall, the risk factor control reached the pre-specified intensity. Plaque thickness, and hence luminal narrowing, significantly diminished at one year (from 1.50±0.48 to 1.24±0.42mm; p Conclusion: Intracranial plaques might regress and positively remodel under intensive risk factor control. These morphologic changes might stabilise the plaques, alleviate unfavourable hemodynamics across the steno-occlusion, and hence reduce the risk of plaque rupture or platelet aggregation.

Background and Objectives: Blood pressure variability (BPV), heart rate variability (HRV) and baroreflex sensitivity (BRS) as measures of autonomic function might provide prognostic information in ischemic stroke. We aimed to study noninvasive beat-to-beat assessment of BPV, HRV and BRS in the acute phase of ischemic stroke to determine whether any of them predicted clinical outcome. Methods & Patients: Consecutive ischemic stroke patients within 7 days of symptom onset were enrolled. The frequency components of BPV and HRV by means of power spectral analysis [very low frequency (VLF; < 0.04 Hz); low frequency (LF; 0.04-0.15 Hz); high frequency (HF; 0.15-0.40 Hz); power spectral density (PSD; Results: 82 patients were recruited (mean age, 64.6 ± 9.9 years; 89.3% males). Univariate analysis showed that there were significant differences in National Institutes of Health Stroke Scale (NIHSS) at recruitment, VLF diastolic BPV, VLF, HF and PSD systolic BPV, and down ramp BEI between the good and poor outcome groups (all P < 0.05). After adjusting for NIHSS, multivariate logistic regression showed that only HF systolic BPV (OR 1.320; 95% CI, 1.050-1.659; P=0.017) and down BEI (OR 0.950; 95% CI, 0.912-0.990; P=0.014) were independently correlated with poor functional outcome. Conclusions: Beat-to beat highly variable systolic blood pressure and impaired BRS as evaluated by decreased down BEI are associated with an unfavorable functional outcome after acute ischemic stroke. Important prognostic information can be readily obtained from a short period of noninvasive hemodynamics monitoring in the acute stroke patient.

Objective: Although Magnetic Resonance Imaging (MRI) vessel wall imaging could visualize the pathology of intracranial arterial disease, signal changes are poorly interpreted due to lacking of cerebral artery specimens. Based on a MRI-histology comparison study on a series of post-mortem cerebral arteries, we aimed to examine the occurrence of hyper-, iso- and hypo-intensity on T1-weighted fat-suppressed images of MCA plaques, which might be suggestive of different plaque components. Methods: Fifty-eight pairs of MCAs were imaged at 1.5T MRI with T1-weighted Table 1: The distribution of different atherosclerotic phenotypes among MCA plaques with iso-, hyper- and hypo-intensity on T1-weighted fat-suppressed images fat-suppressed- and T2-weighted sequence. MRI was performed in the postmortem brains to scan the cross-sections of MCAs with barium expanding the artery lumen. The MCAs were then removed for histopathologic processing and atherosclerotic plaque classification, which was used as a reference standard to interpret the signal changes on MRI pictures. Results: A total of 76 MRI vessel wall images were adequate for signal changes interpretation. On T1-weighted fat-suppressed images of MCA plaques, hyper-intensity was revealed on 34 vessels (44.7%), iso-intensity on 24 vessels (31.6%) and hypo-intensity was revealed on 18 samples (23.7%). There was a trend that iso-intensity indicated lower grade atherosclerosis and hypo-intensity represented advanced atherosclerosis, while hyper-intensity was suggestive of median grade atherosclerotic plaques. Further analysis demonstrated that nearly all hypo-intensity was found to be histology-verified advanced atherosclerosis with lipid core formation. Interpretation: Signals of hypo-intensity on T1-weighted fat-suppressed images of MCA plaques may be useful in stratification of stroke patients with intracranial atherosclerosis.

Background: Intracranial arterial stenosis (ICAS) is a predominant cause of ischemic stroke in Asia. Changes of the signal intensities across ICAS lesions on time-of-flight magnetic resonance angiography (MRA) have been indicated to partially reflect the hemodynamic significance of the lesions, which we aimed to verify by correlating with cerebral perfusion features provided by CT perfusion imaging. Methods: Ischemic stroke or transient ischemic attack patients with unilateral symptomatic stenosis (≥50%) of intracranial internal carotid artery or middle cerebral artery were included in this study. Change of signal intensities across an ICAS lesion on time-of-flight MRA was calculated by the distal and proximal signal intensity ratio (SIR). Cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) within the middle cerebral artery territory of ipsilateral and contralateral hemispheres were evaluated on the CT perfusion images at the basal ganglia level. Relative CBV, CBF and MTT were defined as the ratios of the parameters obtained from ipsilateral and contralateral hemispheres. The relationships between SIR and CT perfusion parameters were analyzed. Results: Fifty subjects (74% male, mean age 62.84) were recruited. Overall, mean SIR was 0.77 ± 0.17. SIR of ICAS significantly, linearly and negatively correlated with ipsilateral CBV (r = -0.335, P = 0.017), CBF (r = -0.312, P = 0.028), and MTT (r = -0.301, P = 0.034), and relative MTT (r = -0.443, P = 0.001). Conclusions: Changes of the signal intensities across ICAS lesions on time-of-flight MRA may be a simple marker to reflect cerebral perfusion changes in patients with symptomatic ICAS.

We studied 590 asymptomatic villagers aged > or =40 years in Liangbei County in central rural China and found 41 subjects (prevalence 6.9%) with intracranial atherosclerosis. In a multivariate analysis, the significant risk factors for intracranial stenosis were hypertension (OR 2.53; 95% CI 1.12 to 5.72), glycosuria (OR 3; 1.19 to 7.97), heart disease (OR 4; 1.39 to 11.6), and family history of stroke (OR 5.2; 1.38 to 20). Intracranial atherosclerosis is not uncommon among asymptomatic Chinese subjects.

To assess the prognostic value of computed tomography (CT) in hyperacute middle cerebral artery (MCA) infarcts.The CT features, total CT score, and National Institutes of Health Stroke Scale (NIHSS) score were correlated with the 30-day mortality in 16 patients with a hyperacute MCA infarct.Admission NIHSS scores were significantly lower in the survival group (P = 0.016). The extent of infarct, attenuation of corticomedullary differentiation, and total CT score were associated with 30-day mortality (P0.05). In prediction of mortality, extent of an infarct67% gave sensitivity, specificity, positive predictive value, and negative predictive value rates of 86%, 100%, 100%, and 90%, respectively. Attenuation of corticomedullary differentiation gave sensitivity, specificity, positive predictive value, and negative predictive value rates of 86%, 89%, 86%, and 89%, respectively. An NIHSS score28 gave sensitivity, specificity, positive predictive value, and negative predictive value rates of 86%, 67%, 67%, and 86%, respectively. A CT score4 gave sensitivity, specificity, positive predictive value, and negative predictive value rates of 86%, 78%, 75%, and 88%, respectively.Computed tomography features and the admission NIHSS score are important predictors of survival in hyperacute extensive MCA infarcts.

Background and Purpose— Both dementia and stroke are major health problems in Chinese societies. Stroke is a frequent cause of dementia. Only a few studies have been published on poststroke dementia (PSDE), none of which has investigated a consecutive stroke cohort in Asian patient populations. The objective of this study was to examine the prevalence and clinical correlates of PSDE in Chinese stroke patients in Hong Kong. Methods— Two hundred eighty stroke patients consecutively admitted to the medical wards of a university-affiliated regional hospital were interviewed by a psychiatrist 3 months after stroke. The presence of dementia and vascular dementia was diagnosed according to the Diagnostic and Statistical Manual , 4th edition. In addition, a wide range of demographic and clinical variables were examined. Results— Fifty-five participants (20%) had PSDE. Univariate analysis found that PSDE was associated with age; level of education; prestroke Rankin Scale score; prestroke Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) score; National Institutes of Health Stroke Scale (NIHSS) best language score, dysarthria score, and total score; urinary incontinence; cortical infarct; leukoaraiosis; bilateral lesions; number of lesions; involvement of middle cerebral artery circulation; and cerebral atrophy index. Multivariate logistic regression suggested that prestroke IQCODE score, NIHSS total score, leukoaraiosis, involvement of middle cerebral artery territory, and cerebral atrophy index were independent risk factors of PSDE. After removal of 22 patients with prestroke dementia, which was defined as a prestroke IQCODE score ≥4.0, the frequency of PSDE dropped to 15.5%. Furthermore, involvement of the middle cerebral artery territory and cerebral atrophy index were replaced by level of education and bilateral lesions as independent predictors in the final logistic model. Conclusions— PSDE is common among Chinese stroke patients in Hong Kong. Its frequency is comparable to that in white populations. The clinical determinants of PSDE, after the exclusion of patients with prestroke dementia, include premorbid level of cognitive function, severity of stroke, leukoaraiosis, level of education, and bilateral lesions.

Objectives: Frontal Assessment Battery (FAB) is a valid and reliable screening test for evaluating executive dysfunction among whites with frontal and subcortical degenerative lesions. We studied the properties of a Chinese version of FAB (CFAB) in evaluating executive dysfunction among Chinese stroke patients with small subcortical infarct. Methods: Concurrent validity was evaluated using Wisconsin Card Sorting Tst (WCST) and Mattis Dementia Rating Scale– Initiation/Perseveration Subset (MDRS I/P) among 41 controls and 30 stroke patients with small subcortical infarct. Discriminant validities of CFAB and its subitems were compared with those of MiniMental State Examination (MMSE). Internal consistency, test-retest, and interrater reliability of CFAB were evaluated. Results: The CFAB had low to good correlation with various executive measures: MDRS I/P (r = 0.63, p < 0.001), number of category completed (r = 0.45, p < 0.001), and number of perseverative errors (r = �0.37, p < 0.01) of WCST. Among the executive measures, only number of category completed had significant but small contribution (6.5%, p = 0.001) to the variance of CFAB. A short version of CFAB using three items yielded higher overall classification accuracy (86.6%) than that of CFAB full version (80.6%) and MMSE (77.6%). Internal consistency (alpha = 0.77), test-retest reliability (rho = 0.89, p < 0.001), and interrater reliability (rho = 0.85, p < 0.001) of CFAB were good. Conclusion: Although CFAB is reliable, it is only moderately valid in evaluating executive dysfunction among Chinese stroke patients with small subcortical infarct. The clinical use of CFAB in the evaluation of executive dysfunction among this group of patients cannot be recommended at this stage.

Background and Purpose— Cerebral microbleeds (MBs) detected by gradient-echo MRI are considered evidence of advanced microangiopathy with potential for further bleeding. The goal of this study was to determine whether the presence of MBs is a risk factor for subsequent intracerebral hemorrhage among patients with acute ischemic stroke. Methods— We prospectively examined patients hospitalized with acute cerebral infarction with gradient-echo T2*-weighted MRI for the presence of MBs. We recorded demographics, medical history, and stroke severity. Patients were then followed up for the development of stroke, other vascular events, and death. Results— One hundred twenty-one consecutive patients with a mean age of 67.96±10.97 years were recruited. MBs were present in 43 patients (35.5%). During follow-up of 27.15±11.68 months, 16 patients had recurrent stroke. There was no difference between patients with or without MB for the development of ischemic stroke (5 and 6 respectively, P =0.841). However, 4 patients (9.3%) with MBs and 1 patient (1.3%) without an MB had intracerebral hemorrhage during follow-up ( P =0.053). Of the 5 patients who developed subsequent intracerebral hemorrhages, 3 were treated with aspirin and 2 with anticoagulation. Two of the intracerebral hemorrhages occurred in the site where asymptomatic MBs were found at baseline. Conclusions— MBs appear to be a risk factor for subsequent intracerebral hemorrhage among patients with ischemic stroke in this small cohort of Chinese stroke patients. A large cohort study is required to confirm this observation.

Background: Success in clinical trials of intracranial atherosclerosis (ICAS) hinges upon the definition of high-risk patients. Noninvasive computational fluid dynamics (CFD) of stenotic lesions may enhance therapeutic decision-making, yet the wide hemodynamic variation may limit the snapshot data of CFD. We determined whether different physiologic parameters may change downstream cerebral hemodynamics in patients with ICAS. Methods: Based on degree of stenosis, patients were divided into a moderate (50-69%) and severe group (70-99%). CFD models were made using CTA source images of patients with symptomatic middle cerebral artery stenosis. Inlet boundary conditions were defined using three ranges (2.5, 50, and 97.5 percentiles) of systolic BP (109.2, 158, and 225 mmHg) and hematocrit (27.3, 40.2, and 48.8). According to systolic BP and hematocrit, 9 distinct scenarios were simulated. Ratio of pressure was calculated using the simulated pressure at pre- and post-stenotic segments. Ratio of shear strain rate (SSR) and velocity were assessed between throat and proximal normal segment. A linear mixed model was used for the statistical analysis of repeated simulations. Results: Among the 56 patients, 32 (57.1%) patients had moderate stenosis and 24 (42.9%) had severe stenosis. Patients with severe stenosis showed unfavorable hemodynamics in terms of ratio of pressure, velocity, and SSR comparing with moderate stenosis group. A linear mixed model revealed that ratio of pressure was predicted by systolic BP X stenosis group interaction (p = 0.036). These pressure drops were associated with systolic BP (p Conclusions: Downstream blood flow may be significantly altered by systolic BP along with severity of stenosis. As individual patient’s specific anatomy influences hemodynamics, physiologic conditions may superimpose further changes in post-stenotic blood flow in patients with ICAS.

Background — Serial changes of flow velocities of transcranial Doppler ultrasound (TCD) in symptomatic middle cerebral artery (MCA) occlusive disease may be related to the occurrence of further vascular events, but prospective data are lacking. Methods — We conducted a prospective study on patients with cerebral ischemia who were hospitalized with symptomatic MCA stenosis or occlusion. We repeated TCD examinations 6 months after the initial examinations and recorded any stroke or coronary events during this period. The changes of MCA flow velocities were categorized as normalized artery, stable artery, and progressed artery, which were determined according to the changes of MCA velocities at 6 months. Results — We studied 143 consecutive patients who had relevant MCA occlusive diseases (107 with stenosis and 36 with occlusion). At 6 months, the velocities in the MCA returned to normal in 42 patients (29%), they were stable in 80 patients (62%), and they progressed in 13 patients (9%). The number of clinical events varied significantly among the 3 groups: there were 2 patients (4.8%) with clinical events in the normal group, 11 patients (12.5%) with clinical events in the stable group, and 5 patients (38.5%) with clinical events in the progressed group ( P =0.004). The 18 recurrent events included 10 recurrent strokes, 5 transient ischemic attacks, and 3 acute coronary syndromes. Conclusions — Progression of MCA occlusive diseases is associated with an increased risk of vascular events. Further studies are required to establish the value of serial TCD examinations in predicting future clinical events.

Objective: To identify the clinical and radiologic features of intracerebral hemorrhage (ICH) in aspirin users.Background: Although the benefits of aspirin outweigh its hemorrhagic risks for patients at high risk of vascular diseases, prolonged use of aspirin is associated with an increased risk of ICH.Methods: The authors enrolled consecutive patients with acute stroke who were admitted to a regional hospital from 1993 to 1998 into a stroke registry. From this registry, they identified all stroke patients who had ICH confirmed by CT scan and then selected those taking regular aspirin before ICH as the study group. For each study patient, they selected the immediate next two patients with ICH but not taking aspirin as controls.Results: The authors identified 58 aspirin users and 1193 nonusers among all patients hospitalized for ICH. From the group of nonusers, they selected 116 patients as controls. The locations of the hematoma were different (p = 0.002), with more lobar hematoma in the aspirin group (32.8%) than in the control group (10.3%). Prior cerebrovascular disease was the reason for taking aspirin in 37 (64%) patients but five patients had prior ICH.Conclusions: The propensity for lobar hematoma in aspirin-associated ICH suggests its pathology may be somewhat different from spontaneous ICH among nonaspirin users. Further research to examine the risks and benefits of aspirin use in certain subgroups at risk of both thrombotic and hemorrhagic events is needed.

Background and Purpose: External counterpulsation (ECP) is a novel noninvasive method used to augment cerebral blood flow which may benefit ischemic stroke patients. We aimed to explore the association between the degree of cerebral blood flow augmentation by ECP and clinical outcome after acute ischemic stroke. Methods: Acute ischemic stroke patients within 7 days of symptom onset were recruited into this study. On admission, bilateral middle cerebral arteries of subjects were monitored using transcranial Doppler (TCD). Flow velocity changes before, during, and after ECP were, respectively, recorded for 3 minutes. Cerebral augmentation index (CAI) was the increase in percentage of middle cerebral artery mean flow velocity during ECP compared with baseline. TCD data were analyzed based on ipsilateral or contralateral to the infarct side. Modified Rankin Scale (mRS) was evaluated 3 months, 6 months and 1 year after ischemic stroke onset. We stratified the patients into two groups (good outcome: mRS 0~2; poor outcome: mRS 3~6) at each measurement time point. Results: 72 patients were recruited (mean age, 63.8±10.7 years; 87.5% males). At month 6 and year 1 after stroke onset, univariate analysis showed that admission National Institutes of Health Stroke Scale (NIHSS) was significantly lower and ECP therapy duration was longer in good outcome group; while the ipsilateral CAI was significantly lower in good outcome group than those in poor outcome group (3.71±4.94 versus 7.73±7.66, P=0.044; 3.50±4.73 versus 8.58±7.72, P=0.015 respectively). Multivariate logistic regression showed that ipsilateral CAI and baseline NIHSS were independent predictors for a favourable outcome at these two measurement points. Conclusions: The degree of cerebral augmentation on ipsilateral to the infarct side by ECP is found to be an important predictor for long-term good outcome in acute ischemic stroke patients, in addition to the well-known prognostic factors such as NIHSS.

Multiple acute cerebral infarcts (MACIs) detected by diffusion-weighted imaging (DWI) may indicate an unstable source of thromboembolism. The authors studied 119 consecutive acute ischemic stroke patients within 24 hours of onset with DWI. MACIs were present in 20 patients (16.8%). During the follow-up period, there were 15 recurrent strokes, 3 acute coronary syndromes, and 5 deaths. MACI was the only significant independent predictor for vascular events and death (odd ratio [OR]] = 4.34; p = 0.001) and stroke recurrence (OR = 5.93; p = 0.001).

Background: External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion but the optimal use of ECP in ischemic stroke has not been well documented. We aim to investigate the effects of increasing ECP treatment pressure on cerebral blood flow and blood pressure (BP). Methods: We recruited 38 acute ischemic stroke patients with large artery occlusive disease and 20 healthy elderly. Mean cerebral blood flow velocities (CBFV) of bilateral middle cerebral artery were monitored using transcranial dopper. Continuous beat-to-beat BP was measured via finger cuffs. We started ECP treatment pressure from 150mmHg, then gradually increased to 187.5mmHg, 225mmHg and 262.5mmHg. CBFV and BP were recorded before ECP and during each pressure increment respectively for 3 minutes. CBFV data of patients was analyzed based on whether it was ipsilateral or contralateral to the infarct. Results: Median NIHSS of stroke patients was 5.5 and mean time after stroke onset was 5.24 days. Mean BP was significantly elevated from baseline in both groups after ECP started. BP increase percentages of two groups similarly kept augmented following raised ECP pressure and reach maximium at 262.5mmHg (patients 16.9% vs. controls 16.52% compared with baseline). Under different ECP pressures, ipsilateral mean CBFV of stroke patients increased 5.15% (150mmHg), 4.35% (187.5mmHg), 4.55% (225mmHg) and 3.52% (262.5mmHg) from baseline. All were significantly higher than baseline but did not differ among different pressures. Contralateral mean CBFV changed likewise (5.16%, 4.02%, 3.7% and 3.34% increase from baseline). Mean CBFV of controls under ECP pressures did not increase from baseline. Conclusion: The increasing treatment pressure of external counterpulsation continuously augments blood pressure but not cerebral blood flow velocity of ischemic stroke patients with large artery occlusive disease. Cerebral blood flow velocity of stroke patients significantly increases from baseline under ECP pressure of 150mmHg but it reaches a plateau as ECP pressure further raises. Among 4 ECP pressures above, 150mmHg is the optimal treatment pressure for ischemic stroke due to higher risks of hypertension-related complications in acute stroke with higher ECP pressure.

Background and Purpose: Ethnic differences have been reported between Asians and Whites in the prevalence of certain stroke subtypes. However, it is unknown if such differences exist with respect to manifestations of cerebral small vessel disease. We compared the prevalence of white matter lesions [WML], lacunes, and microbleeds between Han Chinese and White Australian individuals randomly selected from their respective populations. Methods: Magnetic resonance imaging (1.5 Tesla) was performed on participants of the Shanghai Aging Study (n=321, mean age 69±6 years) and Tasmanian Study of Cognition and Gait (n=397, mean age 72±7 years). A single expert rater recorded measures of WML, lacunes, and microbleeds. We compared lesion prevalence between age- and gender-matched subgroups from the two study population. Among all subjects (n=718), we used multivariable logistic regression to examine if ethnicity was associated with the presence of these lesions. Results: The prevalence rates of confluent WML, lacunes, and microbleeds among Chinese and Whites were 37% vs. 34% (p=0.09), 29% vs. 34% (p=0.24), and 9% vs. 11% (p=0.59), respectively. Subgroup analysis among age- and gender- matched subjects confirmed that confluent WML was more common among Chinese (38.5%) than Whites (28.4%, p=0.01). In multivariable regression, Chinese had a higher risk of confluent WML (odds ratio 1.53, 95% confidence interval 1.04-2.24, p=0.03) independent of other risk factors, but no differences were seen for lacunes and micro bleeds. Conclusion: In this population-based cross-national comparison, Chinese had a greater risk of moderate-to-severe WML than white Australians, but had a similar risk of lacunes and microbleeds.

Background and Purpose:— Intracranial arterial stenosis (ICAS) is the predominant cause of ischemic stroke or transient ischemic attack (TIA) in Asia. Change of signal intensities (SI) across an ICAS on magnetic resonance angiography (MRA) may reflect hemodynamic severity of such lesions. Methods:— In-patients with a symptomatic single ICAS of anterior circulation on 3D time-of-flight MRA were recruited. Baseline and 1-year follow-up data were collected. Signal intensity ratio (SIR) was calculated to represent change of SIs across an ICAS on maximum intensity projections: SIR=(mean post-stenotic SI - mean background SI)/(mean pre-stenotic SI - mean background SI). Acute infarct volume was measured on diffusion-weighted images (DWI). Relationships of SIR and baseline characteristics as well as 1-year outcomes were evaluated. Results:— Thirty-six subjects (86.1% males, mean age 55.0 years) were recruited. Overall, mean SIR was 0.84±0.23. Mean SIR of the 23 (63.9%) anatomically severe stenoses was insignificantly lower than the 13 (36.1%) moderate stenoses (0.80±0.23 versus 0.92±0.21, p=0.126). The median baseline infarct volume for the 28 (77.8%) subjects with lesions on DWI was 2.40 cm 3 (IQR 0.80 to 5.78). SIR and acute infarct volume were significantly, linearly and negatively correlated, Spearman correlation coefficient being -0.471 (p=0.011). Two patients (5.6%) had recurrent ischemic strokes at 1-year follow-up. SIR values or acute infarct volumes were unrelated to 1-year outcomes in this initial study. Conclusion:— Change of signal intensity across ICAS on MRA may reflect hemodynamic and functional severity of the lesion. Future studies are warranted to further verify the relationship between this index and prognosis of stroke patients.

Background and Purpose— Carotid atherosclerosis is not neglectable as a cause for stroke in China, despite of low prevalence. This study was performed to evaluate the association between its ultrasonographic markers with metabolic syndrome (MetS). Methods— This was a community-based cross-sectional study. Demographics, common vascular risk factors, and results of fasting blood analysis were collected at baseline. MetS was defined as ≥3 following conditions or receiving specific treatment: abdominal obesity, elevated triglycerides, low high-density lipoprotein cholesterol, hypertension and impaired fasting blood glucose. All subjects underwent carotid duplex ultrasonography. Mean carotid intima-media thickness (CIMT) of bilateral common carotid arteries was used as the CIMT value for a single subject. CIMT within the 4th quartile was regarded as increased CIMT. Carotid plaque was defined as a focal CIMT of >1.5 mm. Results— A total of 653 subjects (mean age 55.1±10.4; 47.2% male) were recruited. MetS was found in 188 (28.8%) subjects (30.8% in male and 27.0% in female). Mean CIMT was 0.74±0.12 mm. Increased CIMT and carotid plaques were detected in 163 (25.0%) and 95 (14.5%) subjects, respectively. In multivariate linear regression, CIMT significantly increased with increasing numbers of MetS components (P Conclusion— MetS may be independently associated with early stage but not later and advanced stages of carotid atherosclerosis in community residents in China.

Background: Radiation-induced vasculopathy (RIV) predisposes survivors of head-and-neck cancers to refractory ischemic strokes. We aimed to investigate the angiographic extent and morphological attributes of symptomatic RIV. Methods: The study was approved by the Institutional Review Board and each participant provided an informed consent. One hundred thirty patients with ischemic strokes attributed to high-grade carotid stenoses (>60%) were recruited for digital subtraction angiograms (DSA). Among the enrolled patients, 65 had prior curative intent radiotherapy for head-and-neck cancers. The remaining 65 control patients who had no radiotherapy were presumed to have atherosclerotic vasculopathy. DSA revealed both carotid and vertebro-basilar circulations from the level of aortic arch up to intracranial branches. A radiologist blind to the group assignment recorded the distribution and characteristics of both stenotic and non-stenotic lesions. Fetal variant or incompetence of the circle of Willis, if any, was also documented. Results: The baseline characteristics of RIV and control patients were comparable except a lower prevalence of hypertension and diabetes mellitus in RIV group (p were atherosclerotic. Atherosclerotic stenoses were predominantly focal, involving the internal carotid artery adjacent to the bifurcation (93/103, 90.29%). RIV stenoses, in contrast, harbored more frequently at common carotid artery (96/176, 54.55%) and was associated with more tandem lesions (29.23% vs 10.77%, p Conclusion: Radiation-induced carotid disease was frequently bilateral and associated with concurrent tandem and vertebra-basilar steno-occlusions. Fetal variant or incompetence of the Circle of Willis may potentiate further the hemodynamic insufficiency.

A Chinese woman aged 41 years sought treatment at the Prince of Wales Hospital in Hong Kong in November 2001 for sudden-onset right eye blindness. She had good heath in the past and had a normal spontaneous nontraumatic delivery 2 months previously. She had acute loss of vision predominantly affecting the lateral aspect of right eye, which gradually resolved in few days with mild residual blurred vision. There was no preceding headache, neck pain, or other neurologic complaints. There was no recent history of trauma or exercise that involved excessive neck movement, such as yoga. On detailed questioning about any recent abnormal posture or exercise, she reported she had constant neck tilting to the right side every night since her baby was born 2 months earlier, so that her head was in constant contact with her newborn baby during sleep …

To the Editor: Norrving and Adams, in the recent series of articles entitled “Advances in Stroke 2005,” clearly state the evidence for organized stroke care as inpatients after hospital admission.1 It is clear from their review that stroke unit care confers major survival benefits and reductions in disability. We …