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The role of the infarct location in the development of poststroke agitation (PSA) is largely unknown. This study examined the association between the locations of infarcts and PSA at 9 months following the index stroke in 213 patients with the Chinese version of the Neuropsychiatric Inventory. Compared with the non-PSA group, PSA patients had a higher number and volume of acute pontine infarcts. Ventral pontine and lateral cerebellar infarcts were independent predictors of PSA in the multivariate analysis.

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., (© 2016 The Authors.)

Background and Purpose: Magnetic resonance imaging (MRI) has been widely applied in detecting intracranial large artery stenosis, but there have been few validation studies to compare with histopathology. The aim of the postmortem study is to assess the accuracy of MRI in identifying middle cerebral artery (MCA) stenosis., Methods: We recruited, consecutively, Chinese postmortem autopsies in our hospital during 19 months. 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 studies. With histopathology as a reference standard, the accuracy of MRI was evaluated, and the correlation between MCA stenosis identified by MRI and radiologically or histopathologically evident brain infarcts was investigated., Results: Seventy-six consecutive autopsies were recruited. The sensitivity and specificity of MRI in detecting more than 30% MCA stenosis were 38.6% and 92.2%, with a positive predictive value of 87.2% and negative predictive value of 52.2%, and the corresponding values of MRI in identifying more than 50% MCA stenosis were 57.1%, 90.8%, 50%, and 83.0%, respectively. Both more than 30% and more than 50% MCA stenosis identified by MRI were found to be associated with infarctions in the corresponding MCA territory (P= 0.001, odds ratio = 4.365, 95% CI: 1.684-11.313; and P= 0.039, odds ratio = 2.694, 95% CI: 1.139-6.377)., Conclusions: Our study demonstrates the agreement between ex vivo MRI and histopathology in identifying MCA stenosis, and the correlation between the MCA stenosis identified by MRI and radiologically or histopathologically evident brain infarcts.

Background and Purpose: Controversies still exist as to the neuroimaging determinants of cognitive impairment in cerebral small vessel disease (SVD). The authors studied the neuroimaging correlates of cognitive performances among patients with stroke associated with SVD., Methods: The authors per formed cerebral computed tomography, magnetic resonance imaging, and diffusion-weighted imaging among 74 consecutive patients admitted to the acute stroke unit because of stroke associated with SVD. They examined the association between cognitive performances and the following neuroimaging features: volume of white matter changes (WMC), multiplicity of lacunae, location of lacunae, total cerebral atrophy, and frontal and medial temporal lobe atrophy., Results: Apart from age and education, univariate linear regression analyses revealed that WMC volume, presence of thalamic lacunae, cerebral atrophy, and left frontal lobe atrophy predicted performance on the Mini-Mental State Examination while WMC volume, presence of thalamic infarcts, cerebral atrophy, and frontal lobe atrophy of both sides predicted performance on the Mattis Dementia Rating Scale-Initiation/Preservation subscale. In the multivariate analyses, education (R2=0.22, P<.001), left frontal lobe atrophy (R2=0.10, P=.004), and presence of thalamic lacunae (R2=0.04, P=.049) were found to predict performance on the Mini-Mental State Examination while age (R2=0.23, P<.001) and presence of thalamic lacunae (R2=0.08, P=.011) were found to predict performance on the Mattis Dementia Rating Scale-Initiation/Preservation., Conclusions: Among patients with stroke associated with SVD, thalamic lacunae and frontal lobe atrophy are key determinants of cognitive performances.

Background and Purpose: A new simple visual rating scale can be used in magnetic resonance imaging (MRI) to grade the severity of white matter changes (WMC). The authors sought to study the interobserver variability and the validity of this visual rating scale against a computer-aided quantitative method in measuring WMC., Methods: The authors examined 220 magnetic resonance images from stroke-free patients with traditional risk factors for atherosclerosis and middle cerebral artery stenosis who were participants in a clinical trial requiring MRI examination. The severity of WMC was graded from 0 (no WMC) to 3 (severe WMC). For the quantitative assessment of WMC, the volume of WMC were measured with a computer-aided, automated segmentation method. The interobserver variability was also determined., Results: The mean volumes were significantly different among the different groups, which were scored 1, 2, and 3 (1324.59, 6475.48, and 25,440.05 mm3, respectively; 1-way analysis of variance, P < .001). Interobserver variability for grading WMC was good in different locations of the brain. Excellent results were found in the frontal lobe (kappa = 0.829) and the parietal-occipital lobe (kappa = 0.646), whereas poor results were found in the basal ganglia (kappa = 0.391). There was perfect agreement between the 2 observers in 89.1% for the frontal lobe and 77.0% for the parietal-occipital lobe., Conclusions: The results suggest that this simple visual rating scale is a valid and reliable method for grading WMC in the lobar region but not in the basal ganglion.

Objective: Contrast enhancement is a vital feature of the intracranial atherosclerotic plaque on high-resolution magnetic resonance imaging (HRMRI), but its clinical significance is still unclear. We aimed to quantitatively assess plaque enhancement patterns in the middle cerebral artery (MCA) atherosclerotic plaque. Methods: We conducted a cross-sectional study by prospectively recruiting stroke or transient ischemic attack patients with >30% of MCA stenosis of either side. All patients underwent contrast-enhanced HRMRI scans. Enrolled patients were classified into acute phase (<4 weeks), subacute phase (4–12 weeks) and chronic phase (>12 weeks) groups based on the time interval from stroke onset to imaging scan. Plaque enhancement index was calculated for each MCA lesion at the maximal narrowing site. Results: We identified a total of 89 MCA plaques [53 (60%) symptomatic and 36 (40%) asymptomatic; 57 (64%) acute, 18 (20%) subacute and 14 (16%) chronic] in 58 patients on HRMRI. Among the acute lesions, symptomatic plaques had a significantly stronger plaque enhancement than asymptomatic plaques (symptomatic vs. asymptomatic: 38.9 ± 18.2 vs. 18.2 ± 16.2, p < 0.001). Among the symptomatic lesions, plaque enhancement diminished with increasing time after stroke onset (38.9 ± 18.2, 22.0 ± 22.8, and 5.0 ± 10.1 for acute, subacute, and chronic phase, respectively; p = 0.001). Conclusion: Plaque enhancement in the acute atherosclerotic plaque is closely related to recent ischemic events. In symptomatic atherosclerosis, plaque enhancement regresses over time after ischemic stroke, which may offer the potential to monitor the plaque activity in intracranial atherosclerosis using HRMRI. [ABSTRACT FROM AUTHOR]

Background: Previous studies conflicted in the association between intracranial atherosclerotic stenosis (ICAS) and the severity of white matter changes (WMC). Aims: We aimed to investigate the relationships between the severity of luminal stenosis and the hemodynamic significance of middle cerebral artery (MCA) stenosis, and the severity of ipsilateral WMC. Methods: In this cross-sectional study, patients with a recent ischemic stroke or transient ischemic attack and a 50–99% MCA-M1 stenosis in the Chinese Intracranial Atherosclerosis study cohort were analyzed. The post- to pre-stenotic signal intensity ratio (SIR) was obtained in time-of-flight MR angiography (MRA) to represent the hemodynamic significance of MCA-M1 stenosis, with a lower SIR indicating a hemodynamically more severe lesion. The severity of ipsilesional WMC was assessed by an age-related WMC (ARWMC) scale in T2-weighted fluid attenuated inversion recovery MR imaging. The relationships between the degree of MCA-M1 stenosis, SIR, and ipsilesional ARWMC scale were analyzed. The MCA-M1 lesion with a higher percentage of stenosis was chosen for analyses in patients with bilateral MCA-M1 stenoses. Results: Among 180 subjects (mean age, 64 years), a lower SIR of MCA-M1 stenosis (Spearman correlation coefficient, −0.543; p < 0.001), but not the degree of stenosis (p = 0.93), was significantly linearly correlated with a higher ipsilateral ARWMC. Multivariate ordinal logistic regression identified older age (OR = 1.037; 95% CI, 1.008–1.066; p = 0.011) and lower SIR (OR = 0.010; 95% CI, 0.002–0.058; p < 0.001) as independent predictors for more severe ipsilateral WMC. Conclusion: Patients with hemodynamically more severe ICAS are more likely to have more severe ipsilateral WMC. Longitudinal studies with sequential imaging exams may further reveal the impact of hemodynamic significance of ICAS on the development and progression of WMC. [ABSTRACT FROM AUTHOR]

Background and Purpose: Intracranial vessel wall imaging using MRI has great potential as a clinical method for assessing intracranial atherosclerosis. The purpose of the current study was to compare three 3T MRI vessel wall sequences with different contrast weightings (T1w, PD, T2w) and dedicated sagittal orientation perpendicular to the middle cerebral artery, to the reconstructed sagittal image from a transverse 3D T1w volumetric isotropically reconstructed turbo spin-echo acquisition (VIRTA), and provide a clinical recommendation. Materials and Methods: The above-mentioned sequences were acquired in 10 consecutive Chinese ischemic stroke or TIA patients (age: 68 years, sex: 4 females) with angiographic-confirmed MCA stenosis at 3T. Institutional review board approval was obtained. Two raters qualitatively scored all images on overall image quality, presence of artifacts, and visibility of plaques. Data were compared using Repeated measures ANOVA and Sidak’s adjusted post hoc tests. Results: All sequences except the T2w sequence were able to depict the walls of the large vessels of the Circle of Willis (p<0.05). T1w sagittal oblique VIRTA showed significantly more artifacts (p<0.01). Peripherally located plaques were sometimes missed on the sagittal sequences, but could be appreciated on the transverse T1w VIRTA. Conclusion: With the 3T multi-sequence vessel wall protocol we were able to assess the intracranial plaque with two different image contrast weightings. The sequence of preference to include in a clinical protocol would be the transverse 3D T1w VIRTA based on absence of artifacts, larger coverage including the whole Circle of Willis, and excellent lesion depiction. [ABSTRACT FROM AUTHOR]

Background 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. Methods 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. Results 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). Conclusions The risk factors of MBs in strictly deep or lobar regions differ modestly, which may be related to heterogeneous vascular pathologic changes. [ABSTRACT FROM AUTHOR]

Background and Purpose: Few studies have reported on the risk factors of dilated Virchow-Robin Spaces (dVRS) in large samples of ischemic stroke patients. Little evidence exists regarding the relationship between dVRS and etiologic subtype of ischemic stroke or lacune. We aimed to investigate the risk factors associated with the severity of dVRS in a large sample of ischemic stroke patients. Methods: We consecutively enrolled 1,090 patients who experienced an ischemic stroke within the past seven days and underwent a 3.0 T MRI scan in the Chinese IntraCranial AtheroSclerosis Study (ICAS). Clinical data and cranial MRI information of patients included age, sex, vascular risk factors, dVRS, leukoaraiosis, lacune, and etiologic subtype of ischemic stroke. Analyses were performed regarding the risk factors associated with the severity of dVRS by univariate analysis and multivariable ordinal logistic regression analysis. Results: Through multivariable ordinal logistic regression analysis, age, the severity of leukoaraiosis, lacune, admission National Institutes of Health Stroke Scale (NIHSS) ≤3, and the severity of dVRS in the white matter (WM) and hippocampus (Hip) were correlated with the severity of dVRS in basal ganglia (BG); male, history of hypertension, admission NIHSS ≤3, and the severity of dVRS in BG and Hip were correlated with the severity of dVRS in WM; female, the severity of leukoaraiosis, admission NIHSS >3, small artery occlusion subtype of ischemic stroke, and the severity of dVRS in BG and WM were correlated with the severity of dVRS in Hip. Conclusion: dVRS is an indicator of cerebral small vessel diseases such as leukoaraiosis and lacune. However, the risk factors of dVRS differ in various brain regions. [ABSTRACT FROM AUTHOR]

Background and Purpose: Poststroke fatigue (PSF) is a frequent and persistent problem in stroke survivors. The neuroanatomical model of PSF remains unclear. This study examined the association between PSF and cerebral microbleeds (CMBs). Methods: The sample comprised 199 patients with acute ischemic stroke. A psychiatrist who was blind to the subjects' radiological data administered the Chinese version of the Fatigue Severity Scale. PSF was defined as a Fatigue Severity Scale score of 4.0 or more. The locations of CMBs were evaluated with magnetic resonance imaging within 7 days of admission. Results: Of the 199 patients screened, 47 (23.6%) had PSF. The PSF group had a higher Geriatric Depression Scale score (p < 0.001) and a trend for a higher age (p = 0.074). The proportion of patients with deep CMBs was significantly higher in the PSF group (66.0 vs. 48.7%; p = 0.038). The presence of deep CMBs was a significant independent predictor of PSF with an odds ratio of 2.68 (p = 0.016). Conclusion: The results suggest that deep CMBs are associated with a higher risk of PSF. Further studies are needed to clarify whether CMBs affect the clinical presentation, treatment response and outcome of PSF. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Aim High serum bilirubin predicts depression in non-stroke subjects, but it is unknown whether it also predicts post-stroke depression ( PSD). This study examined the association between the risk of PSD and bilirubin level. Methods Six hundred and thirty-five patients with acute ischemic stroke in Hong Kong were recruited. Serum total bilirubin, alanine transaminase and alkaline phosphatase levels were measured in all patients during their hospital stay. A psychiatrist gave the Structured Clinical Interview for DSM-IV to all patients 3 months after the index stroke, with 61 patients diagnosed with PSD: 27 with major depression, 24 with minor depression and 10 with dysthymia. Results In the full sample, the 25%, 50% and 75% percentile bilirubin levels were 7.0, 10.0 and 14.0 μmol/L, respectively. Significant differences were found between the PSD and non- PSD groups in terms of bilirubin level ( P = 0.006). In post-hoc comparisons, the proportion of patients with bilirubin ≥14.1 μmol/L was significantly higher in the PSD group (37.7% vs 19.7%, P = 0.001). In the final regression model, bilirubin level (≥14.1 μmol/L) remained a significant independent predictor of PSD, with an odds ratio of 2.4. Conclusions High bilirubin level is associated with PSD. Further investigations are needed to clarify the underlying pathophysiological link between bilirubin level and PSD. [ABSTRACT FROM AUTHOR]

Objectives: Insomnia is a common complaint in stroke survivors. The purpose of this study was to investigate the clinical and magnetic resonance imaging (MRI) correlates of insomnia symptoms in Chinese ischemic stroke survivors. Methods: A comprehensive psychiatric assessment was performed involving 508 ischemic stroke patients 3 months after their first-ever or recurrent acute stroke. Insomnia symptoms were evaluated with a standard insomnia questionnaire. Depressive symptoms were assessed using the Geriatric Depression Scale (GDS).The evaluation of the MRI scans focused on infarctions, white matter lesions, and microbleeds. Results: One hundred and eight-six patients (36.6% of the sample) had insomnia symptoms. Sixty-four patients (12.6%) had insomnia symptoms with daytime consequences. In the multivariate logistic regression analysis, GDS score (OR = 1.157, p<0.001) and acute frontal lobe infarction (OR = 1.933, p = 0.039) were significant predictors of insomnia symptoms, while the GDS score (OR = 1.251, p<0.001) and diabetes mellitus (OR = 1.959, p¼0.017) were significant predictors of insomnia symptoms with daytime consequences. Conclusions: Insomnia symptoms have a multi-factorial origin in stroke. Besides depressive symptoms, frontal lobe infarction and diabetes mellitus predict insomnia symptoms. [ABSTRACT FROM AUTHOR]

Despite extensive research into poststroke depression (PSD), the role played by lesion location in the pathogenesis of PSD remains uncertain. The aim of this study was to estimate the magnetic resonance imaging (MRI) correlates of PSD in Chinese patients with first or recurrent stroke. A total of 591 patients with acute ischemic stroke admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong were recruited. A psychiatrist assessed all the patients 3 months after the stroke. The psychiatrist used the Structured Clinical Interview for Diagnostic and Statistical Manual, fourth edition (DSM-IV) to confirm whether the patients met the criteria of a depressive disorder. In addition, a host of demographic, clinical, and radiological variables were examined. A tota; of 475 and 116 patients had first and recurrent strokes, respectively. In all, 75 (12.7%) patients received a diagnosis of PSD. In univariate analysis of the MRI findings, the presence of infarcts in the frontal subcortical circuits ([FSC], 66.7% vs 53.3%) was significantly associated with PSD (P = .03) compared to the patients without PSD. The FSC infarct-PSD association remained significant (odds ratio = 2.6) in subsequent logistic regression analysis after adjusting for gender, history of depression, neurological impairment, level of social support, and major life events. In conclusion, FSC infarcts are independent predictors of PSD. Further work is needed to clarify whether these infarcts have an impact on the clinical presentation, treatment responses, and prognosis of PSD. [ABSTRACT FROM AUTHOR]

Moyamoya disease can be associated with autoimmune disease such as thyrotoxicosis, but there has been only one report of association with neuromyelitis optica (NMO). We report another case of this combination with the presence of anti-SSA antibody in addition to the NMO-immunoglobulin G. The patient presented limb weakness along with unsteady gait and numbness. A magnetic resonance imaging (MRI) of the spine showed extensive intramedullary hyperintense signals at C2 to T3 levels. On the other hand, no lesions were found on the MRI of the brain. The patient tested positive for anti-aquaporin-4 antibody and anti-SSA antibody which confirms the diagnosis of NMO. A magnetic resonance angiography scan of the brain revealed a bilateral distal occlusion of the internal carotid arteries (ICAs) as well as occlusions of the middle cerebral arteries (MCAs) with fine collaterals in the region which confirms the diagnosis of moyamoya disease. This report suggests that autoimmunity may be an important factor in the pathogenesis of moyamoya disease in some patients. [ABSTRACT FROM AUTHOR]

The article presents a case study of 83-year old Chinese woman suffering from atrial fibrillation and dementia who was hospitalized due to cardiac arrest. Her magnetic resonance imaging scan before removal of middle cerebral artery (MCA) and after removal was performed for histological comparisons. The results showed hyper intense signal in left MCA and confirmed intraplaque hemorrhage.