Search

This study aimed to develop a sensitive index from transcranial Doppler (TCD) signals for quantitatively evaluating the effects of long-term external counterpulsation (ECP) treatment on stroke rehabilitation. We recruited 27 patients with unilateral ischemic stroke and a good acoustic window within 7 days of stroke onset. 15 of them received 35 daily 1-hour ECP treatment (ECP group) and the others underwent conventional therapy without ECP treatment (No-ECP group). We monitored blood flow in middle cerebral arteries on both sides by TCD, and analyzed them via discrete wavelet analysis method. The overall changes of National Institutes of Health Stroke Scale (NIHSS) and Barthel Index were assessed. A ‘big-wave’ phenomenon was observed in TCD signals of patients in ECP group after 35 days’ treatment, with significant fluctuation in frequency interval from 0.010 to 0.034 Hz as main feature. A new index, which was denoted as ${I}$ , was derived from this phenomenon. The ${I}$ was significantly higher for patients in ECP group than that for patients in No-ECP group after 35-days’ treatment ( ${P} 0.01). And the ${I}$ was positively correlated with NIHSS change in ECP group ( ${P} ). The new index could be used as an effective indicator for evaluating enhancement of endothelial metabolism and neurogenic activity after long-term ECP treatment.

Burning and stabbing pain in the feet and lower limbs can have a significant impact on the activities of daily living, including walking, climbing stairs and sleeping. Peripheral neuropathy in particular is often misdiagnosed or underdiagnosed because of a lack of awareness amongst both patients and physicians. Furthermore, crude screening tools, such as the 10‐g monofilament, only detect advanced neuropathy and a normal test will lead to false reassurance of those with small fiber mediated painful neuropathy. The underestimation of peripheral neuropathy is highly prevalent in the South‐East Asia region due to a lack of consensus guidance on routine screening and diagnostic pathways. Although neuropathy as a result of diabetes is the most common cause in the region, other causes due to infections (human immunodeficiency virus, hepatitis B or C virus), chronic inflammatory demyelinating polyneuropathy, drug‐induced neuropathy (cancer chemotherapy, antiretrovirals and antituberculous drugs) and vitamin deficiencies (vitamin B1, B6, B12, D) should be actively excluded., Diabetic neuropathy has a major impact on morbidity and mortality. However, the diagnosis and management of diabetic neuropathy is South‐East Asia is limited. Clear guidance is required to diagnose and manage patients with diabetic and other neuropathies.

Objective To investigate whether hemodynamic features of symptomatic intracranial atherosclerotic stenosis (sICAS) might correlate with the risk of stroke relapse, using a computational fluid dynamics (CFD) model. Methods In a cohort study, we recruited patients with acute ischemic stroke attributed to 50 to 99% ICAS confirmed by computed tomographic angiography (CTA). With CTA-based CFD models, translesional pressure ratio (PR = pressurepoststenotic /pressureprestenotic ) and translesional wall shear stress ratio (WSSR = WSSstenotic - throat /WSSprestenotic ) were obtained in each sICAS lesion. Translesional PR ≤ median was defined as low PR and WSSR ≥4th quartile as high WSSR. All patients received standard medical treatment. The primary outcome was recurrent ischemic stroke in the same territory (SIT) within 1 year. Results Overall, 245 patients (median age = 61 years, 63.7% males) were analyzed. Median translesional PR was 0.94 (interquartile range [IQR] = 0.87-0.97); median translesional WSSR was 13.3 (IQR = 7.0-26.7). SIT occurred in 20 (8.2%) patients, mostly with multiple infarcts in the border zone and/or cortical regions. In multivariate Cox regression, low PR (adjusted hazard ratio [HR] = 3.16, p = 0.026) and high WSSR (adjusted HR = 3.05, p = 0.014) were independently associated with SIT. Patients with both low PR and high WSSR had significantly higher risk of SIT than those with normal PR and WSSR (risk = 17.5% vs 3.0%, adjusted HR = 7.52, p = 0.004). Interpretation This work represents a step forward in utilizing computational flow simulation techniques in studying intracranial atherosclerotic disease. It reveals a hemodynamic pattern of sICAS that is more prone to stroke relapse, and supports hypoperfusion and artery-to-artery embolism as common mechanisms of ischemic stroke in such patients. Ann Neurol 2019;85:752-764.

Background and Purpose: We assessed the outcomes of dabigatran versus aspirin in a prespecified subgroup analysis of East Asian patients with embolic stroke of undetermined source in the RE-SPECT ESUS trial (Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the Efficacy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate Versus Acetylsalicylic Acid in Patients With Embolic Stroke of Undetermined Source). Methods: Patients with a recent embolic stroke of undetermined source were randomized to dabigatran (150 or 110 mg BID) or aspirin (100 mg QD). The primary efficacy outcome was recurrent stroke; the primary safety outcome was major bleeding. The East Asia cohort was compared with patients from all other countries (non-East Asia cohort). Results: Overall, 988 of 5390 patients (18%) were randomized in East Asia. During a median follow-up of 18.8 months, there was no statistically significant difference in recurrent stroke (hazard ratio, 0.65 [95% CI, 0.41–1.03]) or major bleeding (hazard ratio, 1.04 [95% CI, 0.57–1.91]) in East Asian patients receiving dabigatran versus aspirin. Death from any cause occurred more often in the dabigatran versus the aspirin group (hazard ratio, 3.98 [95% CI, 1.32–12.01]). Conclusions: The treatment effect of dabigatran versus aspirin was consistent between cohorts, with no apparent superiority for dabigatran over aspirin in preventing recurrent stroke in patients with embolic stroke of undetermined source. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02239120.

Intracranial artery calcification (IAC) has been demonstrated to be correlated with ischemic stroke, cognitive decline, and other vascular events by accumulating evidences from both Western and Asian populations. The proposed study aimed to investigate its potential mechanisms by evaluating the blood flow velocity and pulsatility index (PI) of cerebral arteries. Consecutive ischemic stroke patients admitted to the Prince of Wales Hospital were recruited after excluding those with atrial fibrillation or poor temporal window. Quantitative measurements of IAC severity were assessed on brain CT scans. Transcranial Doppler (TCD) ultrasonography was performed to evaluate the blood flow velocity of the middle cerebral artery (MCA) and vertebral-basilar artery (VBA). In total, 318 patients were analyzed. Spearman’s correlation analysis demonstrated both high MCA systolic flow velocity and high MCA PI were correlated with IAC Agatston score, p

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.

External counterpulsation (ECP) is a noninvasive method used to augment cerebral perfusion in ischemic stroke. However, the response of beat-to-beat heart rate variability (HRV) in patients with ischemic stroke during ECP remains unknown.Forty-eight patients with unilateral ischemic stroke at the subacute stage and 14 healthy controls were recruited. Beat-to-beat heart rate before, during, and after ECP was monitored. The frequency components of HRV were calculated using power spectral analysis. Very low frequency (VLF;.04 Hz), low frequency (LF; .04-.15 Hz), high frequency (HF; .15-.40 Hz), total power spectral density (TP;.40 Hz), and LF/HF ratio were calculated.In stroke patients, although there were no statistical differences in all of the HRV components, the HRV at VLF showed a trend of increase during ECP compared with baseline in the left-sided stroke patients (P = .083). After ECP, the HRV at LF and TP remained higher than baseline in the right-sided stroke patients (LF, 209.4 versus 117.9, P = .050; TP, 1275.6 versus 390.2, P = .017, respectively). Besides, the HRV at TP also increased after ECP compared with baseline in the left-sided stroke patients (563.0 versus 298.3, P = .029).Irrespective of the side of the ischemia, patients showed an increased beat-to-beat HRV after ECP. Additionally, sympathetic and parasympathetic cardiac modulations were increased after ECP in patients after right-sided subacute stroke.

Cerebral autoregulation (CA) is a protective mechanism that maintains cerebral blood flow at a relatively constant level despite fluctuations of cerebral perfusion pressure or arterial blood pressure. It is a universal physiological mechanism that may involve myogenic, neural control as well as metabolic regulations of cerebral vasculature in response to changes in pressure or cerebral blood flow. Traditionally, CA has been represented by a sigmoid curve with a wide plateau between about 50 mm Hg and 170 mm Hg of steady-state changes in mean arterial pressure, defined as static CA. With the advent of transcranial Doppler, measurement of cerebral blood flow in response to transient changes in arterial pressure has been used to assess dynamic CA. However, a gold standard for measuring CA is not currently available. Stroke has been the leading cause of long-term adult disability throughout the world. A better understanding of CA and its response to pathological derangements can help assess the severity of stroke, guide management decisions, assess response to interventions and provide prognostic information. The objective of this review is to provide a comprehensive insight about physiology of autoregulation, measurement methodologies and clinical applications in stroke to help build a consensus for what should be included in an internationally agreed protocol for CA testing and monitoring, and to promote its translation into clinical bedside practice for stroke management.

Whether dynamic cerebral autoregulation (dCA) is impaired focally in the affected hemisphere or bilaterally in both the affected and nonaffected hemispheres after ischemic stroke remains controversial. We therefore investigated the pattern of dCA in acute ischemic stroke patients with different subtypes.Sixty acute ischemic stroke patients with unilateral anterior circulation infarct [30 with large artery atherosclerosis (LAA), 13 with small vessel disease (SVD), and 17 with coexisting LAA and SVD] and 16 healthy controls were enrolled. Spontaneous arterial blood pressure and cerebral blood flow velocity fluctuations in both bilateral middle cerebral arteries using transcranial Doppler were recorded over 10 minutes. Transfer function analysis was applied to obtain autoregulatory parameters, autoregulation index (ARI), phase difference (PD), and gain.PD was significantly lower on both the ipsilateral and contralateral sides in the LAA group (ipsilateral, 30.74 degrees; contralateral, 29.17 degrees) and the coexisting LAA and SVD group (20.23 degrees; 13.10 degrees) than that in healthy controls (left side, 51.66 degrees; right side, 58.48 degrees) (all P .05), but there were no significant differences between the 2 sides when compared with each other in all groups. However, in the coexisting LAA and SVD group, phase on both sides was significantly lower when compared with that in the LAA and SVD groups, respectively. The results of ARI were consistent with the findings in PD.The results indicate that dCA is bilaterally impaired in acute ischemic patients with LAA, and the coexisting SVD may aggravate the bilateral impairment of dCA.

Background and Purpose— Poststroke autonomic dysfunction portended an unfavorable prognosis. We investigated whether blood pressure variability (BPV), heart rate variability, and baroreflex sensitivity might predict stroke functional outcome. Methods— We calculated BPV, heart rate variability, baroreflex slope, and baroreflex effectiveness index from a 5-minute beat-to-beat blood pressure and heart rate monitoring within 7 days from the stroke onset. We compared the parameters between patients with a good outcome (modified Rankin Scale score, 0–2) and those with a poor outcome. Results— Among 142 patients (mean age, 63.9±10.2 years; 88.0% men), functional outcome was good in 112 (78.9%) and poor in 30 (21.1%). There were significant differences in admission National Institutes of Health Stroke Scale, prior stroke, high-frequency systolic BPV, low/high-frequency ratio of BPV, baroreflex sensitivity-up, and baroreflex sensitivity-total between the 2 groups (all P P P =0.041), and baroreflex effectiveness index-down (OR, 0.958 [95% CI, 0.924–0.992]; P =0.017) independently predicted a poor functional outcome. Conclusions— A decreased low/high-frequency ratio of systolic BPV and impaired baroreflex sensitivity predicted an unfavorable stroke outcome, in addition to the established prognostic factor such as the National Institutes of Health Stroke Scale.

Background Intracranial arterial calcification (ICAC) is frequently detected on head computed tomography and has been found to be associated with ischemic stroke by recent clinical studies. Aims Based on a hospital-based study, we aimed to compare the occurrence of cerebral microembolic signals (MES) among stroke patients with different degrees of ICAC, which may indicate the potential mechanisms linking ICAC and ischemic stroke in intracranial atherosclerosis patients. Methods This is a post-hoc analysis of our previous clinical study in 2005-2007, recruiting consecutive ischemic stroke patients with middle cerebral artery territory infarctions and good temporal window for MES monitoring. The degrees of ICAC in the Circle of Willis, especially calcification in the ipsilateral intracranial internal carotid artery (iICA), were evaluated both qualitatively and quantitatively on unenhanced head computed tomography. Results Among the 68 recruited patients, MES was detected in 26 patients (38.24%). The overall degree of ICAC in the Circle of Willis was similar between patients with and without MES. For calcification in ipsilateral iICA, the presence of MES was more frequent in the high extent group (widest arc of calcification ≥90°) than in the low extent group (54.2% versus 29.5%, P = .046). Logistic regression found that a high extent ipsilateral iICA calcification was an independent risk factor of MES (odds ratio: 3.134; 95% confidence interval, 1.029-9.543; P = .044). Conclusions MES is frequently detected in patients with a high extent of ipsilateral iICA calcification, which suggests that a high extent of iICA calcification indicates artery vulnerability and accounts for the occurrence of microemboli in the corresponding artery.

Background: CT perfusion (CTP) imaging provides quantitative evaluation of cerebral perfusion flow and volume. Our previous findings showed that benign oligemia caused by intracranial large artery disease may be existent in subacute stroke. Aims: We aimed at comparing the topographic patterns and clinical outcome of stroke patients with and without persistent benign oligemia as defined by CTP imaging. Methods: Consecutive ischemic stroke patients who were referred for CTP in 2009 were screened. The topographic patterns (cortical, borderzone or perforating artery territory infarcts) were assessed by diffusion-weighted imaging (DWI). The clinical outcome was defined by modified Rankin score at 6 months after stroke onset. Results: Totally, 26 stroke patients were recruited. Benign oligemia in subacute stage was detected in 15 patients. The occurrence of borderzone infarction was higher in stroke patients with benign oligemia than those without (p = 0.036). Conclusions: The topographic pattern of DWI may be different between the intracranial arterial disease patients with and without benign oligemia on CTP in subacute stroke.

Though dysfunction of neuromuscular junction (NMJ) is associated with congenital myasthenic syndrome (CMS), the proteins involved in neuromuscular transmission have not been completely identified. In this study, we aimed to identify a novel CMS gene in a consanguineous family with limb-girdle type CMS. Homozygosity mapping of the novel CMS gene was performed using high-density single-nucleotide polymorphism microarrays. The variants in CMS gene were identified by whole-exome sequencing (WES) and Sanger sequencing. A 20 MB-region of homozygosity (ROH) was mapped on chromosome 6q15–21. This was the only ROH that present in all clinically affected siblings and absent in all clinically unaffected siblings. WES showed a novel variant of AK9 gene located in this ROH. This variant was a start-gain mutation and introduced a cryptic 5′-UTR signal in intron 5 of the AK9 gene. The normal splicing signal would be interfered by the cryptic translation signal leading to defective splicing. Another 25 MB-ROH was found on chromosome 11p13–q12 in all siblings. WES showed a homozygous RAPSN pathogenic variant in this ROH. Since RAPSN-associated limb-girdle type CMS was only manifested in AK9 homozygous variant carriers, the disease phenotype was of digenic inheritance, and was determined by the novel disease modifier AK9 which provides NTPs for N-glycosylation. This is the first time that this specific genotype–phenotype correlation is reported. Importantly, the AK9-associated nucleotide deficiency may replete by dietary supplements. Since AK9 is a disease modifier, enhancing N-glycosylation by increasing dietary nucleotides may be a new therapeutic option for CMS patients.

Aggression and agitation are common after a stroke. The association between agitation/aggression following stroke and Health-Related Quality of Life (HRQoL) in stroke survivors is unknown. This study aimed to examine the association between agitation/aggression and HRQoL in Chinese stroke survivors.Three hundred and twenty-four stroke patients entered this cross-sectional study. Agitation/aggression was assessed using the Chinese version of Neuropsychiatric Inventory (CNPI). HRQoL was measured with the Stroke Specific Quality of Life (SSQoL).Three months after the index stroke, agitation/aggression was found in 60 (18.5%) patients. In the agitation/aggression group, 44 patients (73.3%) showed passive agitation/aggression, whereas 16 (26.7%) displayed passive and active agitation/aggression. No patients showed only active agitation/aggression. Patients with agitation/aggression were more likely to have history of diabetes and greater severity of depression, as well as lower SSQoL total score and Personality Changes and Social Role scores. Controlling for diabetes and depression severity did not alter the above results. The Energy and Thinking scores of the SSQoL were significantly lower in the passive/active agitation/aggression group relative to the passive agitation/aggression group (adjusted for CNPI aggression/agitation score).In this study sample, agitation/aggression was preponderantly of the passive type and was associated with poorer HRQoL independently from depression or medical conditions. Patients with both passive and active agitation/aggression had lower Quality of Life (QoL) than patients with only passive agitation/aggression. The causality of the association between low QoL and agitation/aggression needs to be explored in future studies.

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 purpose Baseline collateral status has been correlated with outcomes of acute ischaemic stroke patients receiving intravenous thrombolysis (IVT) in previous studies. We carried out the current systematic review and meta-analysis to synthesize currently available evidence regarding such correlations. Methods Full-text articles published since 2000 were retrieved and screened. The overall effect sizes of good versus poor collateral status over a series of outcomes and certain baseline features were estimated by random-effects models and presented in risk ratios (RRs) or mean differences. Results Overall, 28 (3057 patients) and 14 (1584 patients) studies were included in qualitative and quantitative synthesis, respectively. Compared with poor pre-treatment collateral status, good collaterals showed a beneficial effect over the primary outcome of a favorable functional outcome at 3 or 6 months [RR, 2.45; 95% confidence interval, 1.94–3.09; P 4.5 h (up to 7 h), with the RRs being 2.21, 2.48 and 5.00, respectively (I2 = 53%). Good pre-treatment collaterals were also associated with a smaller infarct size at baseline, and a lower rate of symptomatic intracranial hemorrhage and a higher rate of neurological improvement early after IVT treatment. Conclusions The present study has demonstrated the prognostic value of baseline collateral circulation for outcomes of acute ischaemic stroke patients receiving intravenous reperfusion therapies, studied with different time windows of up to 7 h after ictus for IVT therapy.

Intracranial atherosclerotic disease is the most common cause of cerebral vasculopathy and an important stroke etiology worldwide, with a higher prevalence in Asian, Hispanic and African ethnicities. Symptomatic intracranial atherosclerotic disease portends a recurrent stroke risk as high as 18% at one year. The key to secondary prevention is an understanding of the underlying stroke mechanism and aggressive control of conventional cardiovascular risks. Contemporary treatment includes antiplatelet therapy, optimal glycemic and blood pressure control, statin therapy and lifestyle modifications. For patients with high-grade (70-99%) symptomatic steno-occlusion, short-term dual antiplatelet therapy with aspirin and clopidogrel followed by life-long single antiplatelet therapy may reduce the recurrent risk. Current evidence does not advocate percutaneous transluminal angioplasty and stenting as an initial treatment. External counterpulsation, encephaloduroarteriosynangiosis and remote limb ischemic preconditioning are treatments under investigation. Future studies should aim at predicting patients prone to recurrence despite of medical therapies and testing the efficacy of emerging therapies.

Background and Purpose— Intracranial artery calcification detected by computed tomography is associated with ischemic stroke as an indicator of intracranial atherosclerosis. However, little is known about its histopathology. This study aimed to explore the intracranial calcification patterns and their associations with atherosclerotic plaques. Methods— We recruited 32 adult autopsy cases to assess the calcification patterns and distributions in the middle cerebral artery, vertebral artery, and basilar artery. The relationships of calcification patterns with plaque phenotype and luminal stenosis were evaluated. The calcification patterns on computed tomography were correlated with that on histology. Results— Visible calcifications were detected within 37 (39%) segments, including 25 segments with intimal calcification, 6 segments with internal elastic lamina calcification, 3 segments with adventitial calcification, and 3 segments with concurrent calcification. Calcification occurred more often in the vertebral artery (51%), followed by the middle cerebral artery (35%) and basilar artery (14%; P P P Conclusions— Our histological findings indicate that the presence of intracranial artery calcification has 3 patterns, including intimal, internal elastic lamina, and adventitial calcifications. But only intimal calcification is related with progressive atherosclerotic lesions, indicative of a proxy for intracranial atherosclerosis.

We aimed to investigate the roles of antegrade residual flow and leptomeningeal collateral flow in sustaining cerebral perfusion distal to an intracranial atherosclerotic stenosis (ICAS). Patients with apparently normal cerebral perfusion distal to a symptomatic middle cerebral artery (MCA)-M1 stenosis were enrolled. Computational fluid dynamics models were built based on CT angiography to obtain a translesional pressure ratio (PR) to gauge the residual antegrade flow. Leptomeningeal collaterals (LMCs) were scaled on CT angiography. Cerebral perfusion metrics were obtained in CT perfusion maps. Among 83 patients, linear regression analyses revealed that both translesional PR and LMC scale were independently associated with relative ipsilesional mean transit time (rMTT). Subgroup analyses showed that ipsilesional rMTT was significantly associated with translesional PR ( p

Autonomic dysregulation is common in post-stroke patients. We aimed to correlate beat-to-beat blood pressure variability (BPV) and heart rate variability (HRV) with Ewing's test classification. We enrolled patients with acute ischemic stroke. Autonomic function was assessed by Ewing battery and dichotomized into minor or significant group. Beat-to-beat blood pressure and heart rate were monitored for calculating the frequency components of BPV and HRV using 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;0.40 Hz) and LF/HF ratio]. In minor autonomic dysregulation group, BPV and HRV were similar with those in controls (all p 0.05). However, LF/HF ratio in BPV and HRV significantly reduced in significant autonomic dysregulation group compared with that in controls (all p 0.05). LF BPV in significant group was lower than that in controls. In patients, LF and LF/HF BPVs were positively correlated with parasympathetic parameters, while VLF HRV was negatively correlated with sympathetic parameters and the others were positively correlated with parasympathetic parameters. With cut-off values of 1.80 for LF/HF diastolic BP, 0.96 for the LF/HF systolic BP and 1.80 for LF/HF HRV, the sensitivity (53.80%, 69.20% and 53.80%, respectively) and specificity (92.50%, 80.00% and 92.50%, respectively) of these parameters were observed to predict autonomic dysregulation. Autonomic dysregulation is associated with lower variation of blood pressure and heart rate in acute ischemic stroke. Non-invasive monitoring of beat-to-beat BPV and HRV may be an alternative to autonomic dysregulation measure.

Objective Repeated testing using the Montreal Cognitive Assessment (MoCA) increases risks for practice effects which may bias measurements of cognitive change. The objective of this study is to develop two alternate versions of the MoCA (Hong Kong version; HK-MoCA) and to investigate the validity and reliability of the alternate versions in patients with DSM-5 Mild Neurocognitive Disorder (Mild NCD) and cognitively healthy controls. Methods Concurrent validity and inter-scale agreement were examined by Pearson correlation of the total scores between the original and alternate versions and the Bland-Altman Method. Criterion validity of the two alternate versions in differentiating patients with Mild NCD was tested using receiver operating characteristic curve (ROC) analysis. One-month test-retest and inter-rater reliability were examined in 20 participants. Internal consistency of the alternate versions was measured by the Cronbach’s α. Results 30 controls (age 73.4 [4.5] years, 60% female) and 30 patients (age 75.4 [5.5] years, 73% female) with Mild NCD were recruited. Both alternate versions significantly correlated with the original version (r = 0.79–0.87, p

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.

AIM: Pulse wave velocity (PWV) has been regarded as the “gold standard” measurement of arterial stiffness (AS), but it is still only used in the assessment of central and peripheral arteries. We constructed a new method to evaluate cerebral AS by measuring PWV using transcranial Doppler (TCD). METHODS: In all, 90 healthy subjects who received annual health screening were consecutively enrolled in this study between January 2011 and June 2013. Data on clinical characteristics, brachium–ankle (ba) PWV, and carotid–cerebral (cc) PWV measured with our newly constructed method by two experienced operators were recorded. cc PWV was calculated as the distance between two points in the common carotid artery and proximal part of ipsilateral middle cerebral artery, which was divided by the pulse transit time between these two points where the pulse was measured using TCD. RESULTS: The value of cc PWV was 499.3 ± 78.6 cm/s. Correlation between cc PWV and ba PWV in the assessment of AS was r = 0.794 (P < 0.001). The concordance between both the above mentioned methods was good. Interobserver and intraobserver reliability using interclass correlation for measuring cc PWV were 0.815 (P < 0.001) and 0.939 (P < 0.001), respectively. In multivariable analysis, older age (β = 4.51, P < 0.001) and increased diastolic blood pressure (β = 2.39, P < 0.001) were independently associated with higher cc PWV. CONCLUSION: cc PWV measured using TCD may be a promising method for the assessment of human cerebral AS, which is independently associated with age and diastolic blood pressure.

External counterpulsation (ECP) is a non-invasive method used to augment cerebral perfusion in ischaemic stroke. We aimed to investigate time-course effects on blood pressure elevation and cerebral blood flow augmentation induced by ECP in ischaemic stroke.Patients with acute unilateral ischaemic stroke and large artery occlusive disease were recruited to receive 35 daily 1 h ECP treatment sessions. Serial transcranial Doppler monitoring of bilateral middle cerebral arteries was performed on days 3, 5, 7, 10, 14, 21, 28 and 35 after stroke onset. Flow velocity changes before, during and after ECP and continuous beat-to-beat blood pressure data were recorded. The cerebral augmentation index (CAI) is the increase in the percentage of the middle cerebral artery mean flow velocity during ECP compared with baseline.The CAI in patients with stroke was significantly higher on the ipsilateral side and on the contralateral side on day 3 (ipsilateral CAI, 9.3%; contralateral CAI, 7.2%), day 5 (7.0%; 6.7%), day 7 (6.8%; 6.0%), day 10 (6.0%; 5.1%), day 14 (4.7%; 2.6%) and day 21 (4.1%; 2.2%) after stroke onset than that in controls (-2.0%) (all p0.05). There was a significant trend of decreasing CAI on the ipsilateral and contralateral sides over time after a stroke. Differences in the percentage increase in the mean blood pressure did not change significantly over time in patients with stroke.Blood pressure elevation persists throughout ECP treatment, which consists of 35 sessions. However, cerebral blood flow augmentation may last at least 3 weeks and then appears to return to baseline 1 month after acute stroke onset.

Neurological deterioration (ND) after ischaemic stroke has been indicated as an independent risk factor for poor outcome. Previous studies have focussed on ND within the first few days after symptom onset, but many patients are likely to experience deterioration outside of this time frame. We aimed to investigate the predictors of ND during hospitalisation.Data were obtained from the Chinese Intracranial Atherosclerosis (CICAS) Study, and patients who were diagnosed with ischaemic stroke and arrived at the hospital within 72 hours after symptom onset were included in the present study. Neurological deterioration was defined as an increase in the National Institutes of Health Stroke Scale (NIHSS) score of ≥ 2 points at discharge compared with admission. MR angiography (MRA) and duplex colour Doppler ultrasound were used to document the presence of intracranial or extracranial artery stenosis. Intracranial artery stenosis was defined as a reduction in the artery diameter of ≥ 50% on MRA. Multivariate analyses were conducted to determine the potential predictors of ND during hospitalisation.Of the 1996 patients included in this study, 84 (4.21%) developed ND during hospitalisation. Compared with non-ND patients, ND patients showed higher rates of pneumonia (25.0 vs 9.5%, P 0.001), urinary infection (7.1 vs 1.2%, P 0.01), stroke recurrence (14.3 vs 1.9%, P 0.001), watershed infarct (15.5 vs 5.4%, P = 0.002), intracranial internal carotid artery (ICA) stenosis (11.9 vs 6.0%, P = 0.041), middle cerebral artery (MCA) stenosis (39.3 vs 22.0%, P 0.001) and basilar artery (BA) stenosis (16.7 vs 7.1%, P = 0.011). Multivariate analysis indicated that watershed infarcts (OR, 2.85; 95% CI, 1.04-7.81), MCA (OR, 2.23; 95% CI, 1.17-4.25) and BA (OR, 2.86; 95% CI, 1.19-6.87) stenosis or occlusion were independent risk factors for ND, as was pneumonia (OR, 3.4; 95% CI, 1.46-7.9).Patients with watershed infarcts and MCA or BA stenosis or occlusion should be monitored closely, and various therapeutic strategies should be administered simultaneously to prevent pneumonia during hospitalisation.

Upper limb weakness and incoordination is a common disability following ischemic stroke. Previous studies have showed that the single application of external counterpulsation (ECP) and intermittent theta burst stimulation (iTBS) can effectively enhance the cortical motor excitability and facilitate recovery. However, it remains uncertain if sequential application of these therapies would further augment the recovery. We hypothesize a synergistic effect of ECP followed by iTBS to upper limb function may happen through improvements in both cerebral perfusion and neuron excitability.

OBJECTIVES Stenosis of the intracranial large arteries, especially the middle cerebral artery (MCA), is common in the Chinese population. We conducted a case-control study to investigate clinical and apolipoprotein E (ApoE) gene polymorphism of MCA atherosclerosis in the Chinese population. MATERIALS AND METHODS Polymerase chain reaction-based protocols were used to identify the genotypes of polymorphisms in ApoE genes. Clinical parameters and the genotypes of polymorphisms in the ApoE genes were compared in patients with and without MCA stenosis. The ApoE exon e4 genotypes with risk factors were compared in the patients with and without MCA stenosis. RESULTS In total, 337 ischemic stroke patients were recruited, 156 cases with and 181 without MCA stenosis. Univariate analysis showed that the levels of systolic blood pressure and pulse pressure were higher in the MCA-stenosis group. There were no significant differences in the genotype and allele frequencies of the ApoE polymorphism observed between patients with and without MCA stenosis. However, there was a trend that the MCA-stenosis group tended to have more of genotype e4/e4 (3.8% vs. 0.6%, P=0.052) than the non-MCA-stenosis group. There was no effect of ApoE genotype and genotype-by-environment interactions on ischemic stroke susceptibility. CONCLUSIONS This present study indicated that the hypertension (ie, systolic blood pressure and pulse pressure) and the ApoEe4/e4 genotype may be associated with the occurrence of MCA stenosis in the ischemic stroke Chinese patients.

T2*-weighted gradient echo magnetic resonance imaging is sensitive in detecting cerebral microbleeds (MBs), but there are few reports on the risk factors of MBs in different brain regions. Therefore, we aimed to investigate whether the risk factors associated with the presence of MBs in strictly deep or lobar brain regions were different.This study consisted of 696 consecutive acute ischemic stroke patients from 6 hospitals in the Chinese IntraCranial AtheroSclerosis Study. We evaluated the number and location of MBs, severity of lacune and leukoaraiosis (LA), and etiologic subtype of ischemic stroke. Multivariable logistic regression was used to analyze risk factors of MBs in different brain regions.Among 696 acute ischemic stroke patients, 162 patients (23.3%) had MBs. Of them, 62 patients had strictly deep brain MBs, 49 patients had strictly lobar MBs. There was a significant correlation between the number of MBs, the number of lacune, and the severity of LA (P.0001). In multivariable logistic regression analysis, both strictly deep and strictly lobar brain, MBs were significantly associated with history of cerebral hemorrhage (P = .037 and P = .026, respectively), presence of lacune (P = .004 and P = .032, respectively), and severe LA (P = .002 and P = .008, respectively). However, MBs in strictly deep regions were significantly associated with higher mean arterial pressure (P = .030), and those in strictly lobar brain regions were significantly associated with older age (P = .023).The risk factors of MBs in strictly deep or lobar regions differ modestly, which may be related to heterogeneous vascular pathologic changes.

Background and Purpose— Central autonomic dysfunction increases stroke morbidity and mortality. We aimed to investigate whether poststroke autonomic dysfunction graded by Ewing battery can predict clinical outcome. Methods— In this prospective observational study, we assessed autonomic function of ischemic stroke patients within 7 days from symptom onset by Ewing battery. On the basis of the magnitude of autonomic dysfunction, we stratified patients into significant (definite, severe, or atypical) or minor (normal or early) autonomic function impairment groups and correlated the impairment with the 3-month modified Rankin Scale score (good outcome: modified Rankin Scale score 0≈2; poor outcome: modified Rankin Scale score 3≈6). Results— Among the 150 patients enrolled (mean age, 66.4±9.9 years; 70.7% males), minor autonomic dysfunction was identified in 36 patients (24.0%), and significant autonomic dysfunction was identified in 114 patients (76.0%) based on Ewing battery. In 3 months, a poor functional outcome was found in 32.5% of significant group patients compared with 13.9% in the minor group ( P =0.031). Crude odds ratios of the magnitude of autonomic dysfunction and 3-month unfavorable functional outcome after acute ischemic stroke were 2.979 (95% confidence interval, 1.071–8.284; P =0.036). After adjusting for confounding variables with statistical significance between the 2 functional outcome subgroups identified in univariate analysis (including sex and National Institutes of Health Stroke Scale score on admission), the magnitude of autonomic dysfunction still independently predicted an unfavorable outcome, with an odds ratio of 3.263 (95% confidence interval, 1.141–9.335; P =0.027). Conclusions— Autonomic dysfunction gauged by Ewing battery predicts poor functional outcome after acute ischemic stroke.

Background and purpose Leptomeningeal collateral (LMC) status governs the prognosis of large artery occlusive stroke, although factors determining LMC status are not fully elucidated. The aim was to investigate metrics affecting LMC status in such patients by using computational fluid dynamics (CFD) models based on computed tomography angiography (CTA). Methods In this cross-sectional study, patients with recent ischaemic stroke or transient ischaemic attack attributed to atherosclerotic M1 middle cerebral artery (MCA) stenosis (50%-99%) were recruited. Demographic, clinical and imaging data of these patients were collected. Ipsilesional LMC status was graded as good or poor by assessing the laterality of anterior and posterior cerebral arteries in CTA. A CFD model based on CTA was constructed to reflect focal hemodynamics in the distal internal carotid artery, M1 MCA and A1 anterior cerebral artery. Pressure gradients were calculated across culprit MCA stenotic lesions in CFD models. Predictors for good LMC status were sought in univariate and multivariate analyses. Results Amongst the 85 patients enrolled (mean age 61.5 ± 10.9 years), 38 (44.7%) had good ipsilesional LMC status. The mean pressure gradient across MCA lesions was 14.8 ± 18.1 mmHg. Advanced age (P = 0.030) and a larger translesional pressure gradient (P = 0.029) independently predicted good LMCs. A lower fasting blood glucose level also showed a trend for good LMCs (P = 0.058). Conclusions Our study suggested a correlation between translesional pressure gradient and maturation of LMCs in intracranial atherosclerotic disease. Further studies with more exquisite and dynamic monitoring of cerebral hemodynamics and LMC evolution are needed to verify the current findings.

Background Leukoaraiosis (LA) is an indicator of small vessel disease, but little is known about the relationship between the severity of LA and etiologic subtype of ischemic stroke. Our study aimed to investigate the factors associated with the severity of LA and the relationship between the severity of LA and etiologic subtype of ischemic stroke. Methods A total of 791 patients with first-ever ischemic stroke within 7 days were enrolled in our study. We evaluated cranial magnetic resonance imagings including severity of LA in periventricular and deep white matter, severity of silent lacunar infarcts (SLIs), etiologic subtype of ischemic stroke, and topographic patterns of acute cerebral infarcts. Severity of LA was graded as grade 0 when Fazekas scores = 0, grade 1 when Fazekas scores ranged from 1 to 2, and grade 2 when Fazekas scores were greater than or equal to 3. Multivariable ordinal logistic regression was used to analyze the factors associated with the severity of LA. Results A total of 748 patients (94.6%) had LA, the numbers and proportions of grade 0, grade 1, and grade 2 LA were 43 patients (5.4%), 413 patients (52.2%), and 335 patients (42.4%), respectively. In multivariable ordinal logistic regression analysis, increasing age, higher diastolic blood pressure, admission National Institutes of Health Stroke Scale scores less than or equal to 3, presence of SLIs, and small artery occlusion (SAO) subtype of ischemic stroke were found to be independently associated with higher grade of LA. Conclusions LA is prevalent in first-ever ischemic stroke patients. Severe LA is more frequently associated with higher grades of SLIs and ischemic stroke due to SAO.

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 Changes of signal intensities (SIs) across intracranial atherosclerosis (ICAS) on magnetic resonance angiography (MRA) may reflect hemodynamic impact of the lesion. We evaluated the interobserver reproducibility of an index termed signal intensity ratio (SIR), developed in a previous study to represent the changes of SIs across ICAS on MRA. Methods Symptomatic ICAS on MRA were retrospectively recruited. Two observers respectively evaluated the images and calculated the SIR as follows, blinded to each other's readings: SIR=(mean poststenotic SI − mean background SI)/(mean prestenotic SI − mean background SI). Statistical analyses were performed to evaluate the interobserver reproducibility of this index. Results A total of 102 symptomatic ICASs were enrolled, with 36 (35.3%) lesions of 50%-69% MRA stenoses and others being 70%-99% stenoses or flow void on MRA. Overall, mean SIRs were not significantly different between the 2 observers (.92 ± .17 versus .93 ± .17; mean difference −.006 ± .09; P = .496 for paired t test). Pearson correlation coefficients were >.80 for all analyses, indicating strong linear correlations between SIRs by the 2 observers. Bland–Altman analysis for SIRs of all cases showed no systematic bias between the 2 observers. For different cut-points ranging from .75 to 1.00, the kappa statistics were mostly greater than .6 and interobserver agreements were all greater than 80%, implying substantial agreement between observers. Conclusions SIR was demonstrated to be highly reproducible between observers in the present study. Future studies are warranted to further explore the role of this index in comprehensive evaluation and risk stratification of symptomatic ICAS.

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 Intracranial arterial stenosis (ICAS) is the dominant cause for ischemic stroke worldwide, with hemodynamic compromise as a crucial contributor. Prolonged perfusion is commonly observed in ICAS patients on CT perfusion (CTP) maps, while the clinical significance of this perfusion pattern has not been elucidated. Method Patients having symptomatic ICAS of 50-99% stenosis with sustained downstream cerebral blood flow (CBF) were enrolled in this study. Prolonged perfusion was defined as increased mean transit time (MTT) in vascular territories of the target ICAS on CTP maps. The primary clinical outcome was recurrence of ipsilateral ischemic stroke, and secondary outcome was any ipsilateral ischemic events at 2 years follow-up. Results Of the 95 patients (median age 61y; 70% males) with symptomatic ICAS, 29 patients (30.5%) had prolonged perfusion. Such delayed perfusion was persistent in a majority of patients according to the 1-year imaging follow-up. The prolongation of cerebral perfusion was associated with subsequent risk for ipsilateral ischemic stroke (HR 7.01; 95% CI 1.86-26.46; p = 0.004), but not for any ipsilateral ischemic events (HR 1.52; 95% CI 0.63-3.68; p = 0.348). Further comparison of perfusion measures showed lower CBF (p = 0.034) and higher MTT (p = 0.064) in patients with recurrent ischemic stroke, but not in those with recurrent transient ischemic attack (TIA). Among patients with recurrent stroke, a majority had multiple infarcts along the borderzone regions. Conclusion In patients with symptomatic ICAS, persistent prolonged cerebral perfusion might contribute to the relapse of ischemic stroke, but not TIA.

Background This study aimed to evaluate the 1-year clinical and angiographic outcome of angioplasty and stenting of intracranial atherosclerosis using Wingspan and Gateway system. Methods In this prospective study, patients with symptomatic lesions were treated and followed clinically and angiographically by digital subtraction angiography (DSA) for 1 year. The two primary endpoints were recurrent ipsilateral ischemic stroke and in-stent restenosis (ISR) at 1 year. Secondary endpoints included periprocedural death or stroke and all strokes at 1 year. Potential factors correlated with ISR were studied using univariate and multivariate analysis. Results Treatment was attempted in 65 patients and successfully completed in 61 (93.8%). Fifty-nine patients (44 men, 15 women) aged 62.86±11.38 years with 66 stenoses (average degree of stenosis 71.78±11.23%) underwent clinical and DSA follow-up at 1 year. There were 66 stenotic lesions. ISR occurred in 11 of the 66 lesions (16.7%). Luminal gain occurred in 32 of the lesions (48.5%), an unchanged lumen in 4 (6%) and luminal loss in 30 (45.4%). The periprocedural stroke or death rate was 6.1% (4/65), including three hemorrhagic and one ischemic stroke, all of which occurred at the corresponding site and resulted in death. There were no interval strokes between the periprocedural time and the 1-year follow-up. The occurrence of ISR was correlated with the degree of stenosis before treatment and was not correlated with patient age or sex, vessel diameter, location of stenosis or failure to control risk factors for atherosclerosis. Conclusions One-year clinical and angiographic outcomes of angioplasty and stenting are promising for symptomatic intracranial atherosclerosis.

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.

Objective The caudate nucleus may be involved in the pathogenesis of the fatigue observed in neurological disorders. However, the significance of caudate lesions in poststroke fatigue (PSF) is unknown. This study examined the association between caudate infarcts and PSF. Methods Five hundred Chinese patients with acute ischemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong participated in the study. All participants were assessed for PSF with the Fatigue Severity Scale (FSS) three months after their index stroke. PSF was defined as a mean FSS score of 4.0 or more. Physical functioning and depressive symptoms were measured by the Barthel Index (BI) and the Geriatric Depression Scale (GDS). Results One hundred and twenty-five (25.0%) of the patients had PSF. Compared to the non-fatigue group, the PSF patients were more likely to be women and had hyperlipidemia, lower BI and higher GDS scores. Caudate (8.0% versus 1.3%, p = 0.001) and putamen (19.2% versus 12.0%, p = 0.043) acute infarcts were more common in the PSF group, whereas pons infarcts (13.6% versus 22.2%, p = 0.038) were less common. Acute caudate infarcts remained an independent predictor of PSF in the multivariate analysis, with an odds ratio of 6.4. Conclusions The results suggest that patients with PSF are more likely to have caudate infarcts.

The serotonin receptor 2C (HTR2C) gene has been shown to play a pivotal role in major depression. We examined the association between post-stroke depression (PSD) and polymorphism in HTR2C. A cohort of 223 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 geriatric depression scale score of 7 or above. Possible confounding factors, including previous history of stroke, severity of stroke, level of social support, and recent life events, were investigated. All patients were genotyped for polymorphisms of HTR2C. Separate analyses were performed for males and females. Sixty-one patients were found to have PSD. There were significant associations between the HTR2C gene and PSD status in the male patients, but not in the female ones. After adjusting for possible confounders, the rs12837651 T allele (odds ratio = 4.020) and the rs2192371 G allele (odds ratio = 2.866) were found to be significantly associated with PSD in males. Genetic variation in HTR2C receptors appears to be involved in the pathogenesis of PSD in Chinese males.

Transcranial Doppler ultrasonography (TCD) is the only diagnostic modality that provides a reliable evaluation of intracranial blood flow patterns in real-time. The physiological information obtained from TCD is complementary to the anatomical details obtained from other neuroimaging modalities. TCD is relatively cheap, can be performed bedside, and allows monitoring in acute emergency settings. TCD criteria for intracranial stenosis have been validated against various forms of angiographic studies and serve as reliable tools for screening, diagnostic as well as follow up purposes. TCD findings of intracranial stenosis have acceptable accuracy parameters for anterior as well as posterior circulation. Extended applications of TCD, especially emboli monitoring and assessment of vasomotor reactivity, provide important information about the pathophysiology of cerebrovascular ischemia and risk stratification. Therefore, TCD has become an integral component of the armamentarium of stroke neurologists for understanding stroke etiopathogenesis, planning and monitoring definitive treatment and determining the prognosis. We present the basic principles of TCD, techniques of test performance, diagnostic methods as well as some of the advanced applications of TCD in patients with intracranial stenosis.

Increasing our knowledge about intracranial atherosclerosis (ICAS) natural history and prognostic factors is essential to improve its preventive therapy and thus reduce the dramatic clinical consequences caused by this entity. ICAS is characterized by a chronic and progressive course until it becomes symptomatic, mostly through complication of an unstable intracranial atherosclerotic plaque. Population-based studies in healthy subjects have shown that the prevalence of asymptomatic ICAS is higher in Asian than in Caucasian populations. In both settings, asymptomatic ICAS is associated with classical vascular risk factors and with the metabolic syndrome, and it is burdened with an increasing risk of having incident stroke and cognitive impairment. When it reaches its symptomatic stage, ICAS is a dynamic and aggressive condition, and affected patients are at high risk of having recurrent stroke and other major vascular events. The Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) trial has recently shown a robust impact of intensive medical therapy reducing the risk of clinical recurrence of symptomatic ICAS. However, even under best medical therapy and degree of risk factor control, symptomatic ICAS-related recurrence risk continues to be the highest among all stroke etiologic subtypes. The second part of the chapter reviews the current understanding of prognostic factors that may help discriminate the high-risk ICAS patients, divided into local factors (vulnerable ICAS plaque) and systemic factors (vulnerable ICAS patient). Regarding research on local factors, high-resolution magnetic resonance imaging (HRMRI) is an emerging technique that allows in vivo evaluation of intracranial arterial wall, which is displacing our research focus from intracranial stenosis degree towards intracranial atherosclerotic plaque composition and activity. Characterization of the vulnerable ICAS patient may be improved with biomarker research. The latest contributions in this field help support the hypothesis that inflammation determines the risk of progression and complication of this disease, as it occurs in atherosclerosis affecting extracranial arterial beds.

Recent advances in neuroimaging technologies, such as diffusion weighted magnetic resonance imaging (MRI), perfusion weighted computed tomography (CT)/MRI, MR/CT angiography and Doppler ultrasonography allow us to determine the mechanisms of stroke and transient ischemic attack. In addition, high-resolution vessel wall MRI is nowadays increasingly used to understand the stroke mechanism in patients with intracranial atherosclerosis. Artery to artery embolism, hypoperfusion and the combination of the two are the important stroke mechanisms in patients with extracranial atherosclerosis. In addition to the above two, branch occlusion and in-situ thrombotic occlusion are important stroke mechanisms in patients with intracranial atherosclerosis. Branch occlusion leads to subcortical or brainstem infarcts indistinguishable from infarcts caused by small artery disease. In-situ thrombotic occlusion leads to larger territorial infarcts. However, whole territory infarcts are uncommon due to relatively well developed collateral circulation in these patients. The treatment strategy should be based on the correct understanding of the stroke mechanism in individual patients.

Intracranial atherosclerotic occlusive disease is an important and possibly the most common cause of stroke worldwide. Asian, Black and certain Hispanic populations have a high risk of harboring intracranial occlusive disease. In this chapter we review the epidemiology of intracranial occlusive disease by primarily focusing on studies from China, Japan, Korea, and other Asian countries. In addition, we compare and contrast the information from Asian countries with that from North America and related regions. Finally, we explore hypotheses concerning the origin of race-ethnic differences in the distribution of extracranial and intracranial atherosclerotic disease.

Background Computational fluid dynamics (CFD) allows noninvasive fractional flow (FF) computation in intracranial arterial stenosis. Removal of small artery branches is necessary in CFD simulation. The consequent effects on FF value needs to be judged. Methods An idealized vascular model was built with 70% focal luminal stenosis. A branch with one third or one half of the radius of the parent vessel was added at a distance of 5, 10, 15 and 20 mm to the lesion. With pressure and flow rate applied as inlet and outlet boundary conditions, CFD simulations were performed. Flow distribution at bifurcations followed Murray’s law. By including or removing side branches, five patient-specific intracranial artery models were simulated. Transient simulation was performed on a patient-specific model, with a larger branch for validation. Branching effect was considered trivial if the FF difference between paired models (branches included or removed) was within 5%. Results Compared with the control model without a branch, in all idealized models the relative differences of FF was within 2%. In five pairs of cerebral arteries (branches included/removed), FFs were 0.876 and 0.877, 0.853 and 0.858, 0.874 and 0.869, 0.865 and 0.858, 0.952 and 0.948. The relative difference in each pair was less than 1%. In transient model, the relative difference of FF was 3.5%. Conclusion The impact of removing side branches with radius less than 50% of the parent vessel on FF measurement accuracy is negligible in static CFD simulations, and minor in transient CFD simulation.

To examine the relation between neuroticism and fatigue in Chinese patients with stroke.Cross-sectional study.Acute stroke unit.Survivors of ischemic stroke (N=191) recruited from the acute stroke unit between May 1, 2010, and September 1, 2011.Not applicable.The personality trait of neuroticism was measured with the neuroticism subscale of the Chinese version of the NEO Five-Factor Inventory. The level of fatigue was measured with the Fatigue Assessment Scale. The National Institutes of Health Stroke Scale, Geriatric Depression Scale, Barthel Index, and Mini-Mental State Examination were administered to obtain demographic and clinical information.Fatigue severity 3 months after stroke positively correlated with Geriatric Depression Scale and NEO Five-Factor Inventory neuroticism scores and negatively correlated with the Barthel Index score.Neuroticism, independent of depressive symptoms, is a predictor of fatigue severity 3 months after stroke. Interventions such as psychological screening programs are warranted for early detection of patients at high risk of poststroke depression.

Stroke patients with carotid disease have a high risk of recurrence of disease. By measuring cerebral blood flow volume (BFV) using extracranial duplex technique for clinical estimation of intracranial collaterals, we aimed to investigate the relationship between the presence of intracranial collaterals and stroke recurrence in stroke patients with carotid disease. Consecutive stroke patients indicated for carotid duplex ultrasound investigations in our hospital were recruited during three years' period. Carotid stenosis was diagnosed as ≥50% stenosis and extracranial arterial BFV was measured by using color velocity imaging quantification ultrasound (CVIQ) software. Presence of intracranial collateral flow was defined as a blood flow volume of either ≥370 mL/min in common carotid artery or ≥120 mL/min in vertebral artery. Univariate and multivariate analyses were performed to determine the independent predictors of recurrent stroke. One hundred and twelve stroke patients (19.1%) with ≤50% carotid stenosis were recruited from consecutive ischemic stroke patients. During a mean follow-up of 28.6±13.1 months, recurrent stroke was recorded in 32 (28.6%) out of the total recruited patients. Estimated by blood flow volume measured by CVIQ, the patients with intracranial collateral flow had a lower rate of recurrent stroke than those without (9.5% vs. 33%, P=0.032). After adjusting for potential confounders, the presence of CVIQ-estimated intracranial collateral flow was an independent protector of recurrent stroke (OR, 0.169; 95% CI, 0.034- 0.842; P=0.03). It could be concluded that blood supply through intracranial collateral flow estimated by CVIQ technique may protect stroke patients with carotid stenosis from suffering recurrent stroke.

Objectives The criteria for evaluating cerebral artery stenosis by transcranial Doppler sonography are inconsistent. We aimed to identify the accuracy of transcranial Doppler criteria compared with digital subtraction angiography for diagnosis of anterior circulation artery stenosis. Methods A total of 170 patients who underwent transcranial Doppler sonography and digital subtraction angiography were recruited. The anterior circulation arteries were evaluated by transcranial Doppler sonography and digital subtraction angiography. We defined the best cutoff value for substantial anterior circulation artery stenosis by receiver operating characteristic curve analyses and calculated the sensitivity, specificity, and positive and negative predictive values. Results An anterior circulation artery peak systolic velocity (PSV) of 120 cm/s had the largest area under the receiver operating characteristic curve compared with PSVs of 110, 130, and 140 cm/s and mean flow velocities of 60, 70, and 80 cm/s. The sensitivity, specificity, false-positive rate, false-negative rate, accuracy, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and Youden index for transcranial Doppler sonography were 90.6%, 85.0%, 15.0%, 9.4%, 87.9%, 87.2%, 88.9%, 6.04, 0.11, and 0.756, respectively. The reliability index included the agreement rate and κ value, which were 87.9% and 0.757. Conclusions A PSV of 120 cm/s combined with additional parameters was an accurate criterion for diagnosing anterior circulation artery stenosis. Transcranial Doppler sonography could be considered a valuable method for screening diagnosis of cerebral artery stenosis.

Background Cerebral microbleeds may contribute to cognitive deficits in stroke. Cognitive impairment that does not meet the criteria for dementia (cognitive impairment no dementia) is common in stroke, and patients with such impairment can revert to normal cognition. Aims and hypothesis This study examined the association between cerebral microbleeds and the reversion of cognitive impairment no dementia. Method A total of 328 Chinese patients with acute ischemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong participated in the study. All subjects were assessed for cognitive impairment no dementia with a neuropsychological test battery at three- and 15 months following the index stroke. Of the 180 patients with cognitive impairment no dementia at three-months poststroke, 143 (79·4%) attended the 15-month follow-up. Twenty-nine subjects had reverted from cognitive impairment no dementia to normal cognitive status (reverters), 98 were nonreverters and 16 had progressed to dementia. Results In univariate analysis, the reverters were found to be younger, less likely to have hypertension and cerebral microbleeds, and to have smaller white matter hyperintensity volumes. In multivariate analysis, the absence of cerebral microbleeds remained an independent predictor of reversion with an odds ratio of 4·3. Absence of deep cerebral microbleeds predicted the reversion of the language domain, whereas the absence of lobar cerebral microbleeds predicted the reversion of the visuomotor speed domain. Conclusions The results suggest that the absence of cerebral microbleeds may be associated with a higher likelihood of a reversible cognitive impairment in stroke patients. The mechanism of how this occurs is not well understood.

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.

Tang W-K, Lau CG, Mok V, Ungvari GS, Wong K-S. Burden of Chinese stroke family caregivers: the Hong Kong experience. Objective To ascertain the clinical and sociodemographic factors associated with family caregivers' burden in Chinese patients with stroke in Hong Kong. Design Cross-sectional design. Setting Stroke Clinic. Participants Patients (N=123) from a stroke clinic and their family caregivers. Interventions Not applicable. Main Outcome Measures Predictive factors of family caregivers' burden in Chinese stroke patients in Hong Kong. Caregivers' burden was assessed with the Caregiving Burden Scale (CBS). Patients' and caregivers' sociodemographic data and clinical characteristics were recorded. Physical and psychological conditions were measured and rated with the following instruments: Cumulative Illness Rating Scale, Geriatric Depression Scale (GDS), Barthel Index, Instrumental Activities of Daily Living, Mini-Mental State Examination, Lubben Social Network Scale, Modified Life Event Scale (MLES), Hospital Anxiety and Depression Scale (HADS), and a single question about fatigue. Results In the univariate analysis, the CBS score had significant correlations with certain characteristics of caregivers (sex, GDS, HADS, depressive symptoms, fatigue, and MLES) and those of patients' (sex, age, education, GDS). Regression analysis revealed that caregivers' GDS and patients' education were the independent correlates of the CBS. Conclusions The severity of depressive symptoms in Chinese stroke caregivers and patients' education are independent factors associated with the caregivers' burden. Further studies evaluating interventions on caregivers' burden should include the assessment and management of mood disorders.