White matter hyperintensities: repercussion on grey matter structures of the brain / Hiperintensidades da substância branca: repercussão em estruturas da substância cinzenta do cérebro

The extensive white matter of the brain, which comprises about one half of its volume, is constituted by an intricate and interwoven assemble of nerve fibers. The WMH (leukoaraiosis) represent the most frequent ischemic type of lesion of SVD, affecting the white matter. These lesions may be apparent or normal appearing on neuroimaging. In both cases such lesions may interrupt the affected white matter fibers, with consequent disconnection syndromes, and atrophy of the denervated grey matter structures. These conditions affect the structural neural networks (connectome), with functional repercussion on the cognitive and behavioral domains.

A extensa substância branca do cérebro, que compreende cerca da metade do seu volume, é constituída por um intricado e entrelaçado conjunto de fibras nervosas. As HSB (hiperintensidades da substância branca) (leucoaraiose) representam o mais frequente tipo de lesão isquêmica da DPV (doença dos pequenos vasos) que afeta a substância branca. Essas lesões podem ser aparentes ou de aparência normal na neuroimagem. Em ambos os casos tais lesões podem interromper essas fibras da substância branca, com consequente síndromes por desconexão e atrofia de estruturas de substância cinzenta desnervadas. Essas condições afetam as redes neurais estruturais (conectoma), com repercussão funcional nos domínios cognitivo e do comportamento.

White matter hyperintensities: initial assessments / Hiperintensidades da substância branca: avaliações iniciais

The white matter hyperintensities (WMH, leucoaraiosis) represent the most common kind of ischemic vascular lesion of the white matter due to small vessel diseases, and occurs frequently in the elderly. Consequent to the neuroimaging identification arouse the need for their assessment. The group of Fazekas proposed a systematized semi-quantitative visual scale to score such lesions where two parameters were considered, extent and localization. The original scale was further modified, to a simplified version. Although other more complex scales have appeared, researchers remarked that the relatively simple Fazekas scale, in comparison to the complex ones and to volumetric measures, appeared to be sufficient when analyzing relationships between clinical parameters and WMH load in a clinical setting.

As hiperintensidades da substância branca (HSB, leucoaraiose) representam o tipo de lesão isquêmica mais comum da substância branca decorrente de doenças de pequenos vasos e ocorre frequentemente em idosos. Consequente à identificação por neuroimagem surgiu a necessidade de sua avaliação. O grupo de Fazekas propos uma escala visual semiquantitativa sistematizada para pontuar tais lesões, onde foram considerados dois parâmetros, extensão e localização. A escala original foi modificada para constituir uma versão mais simplificada. Embora outras escalas mais complexas tenham aparecido, pesquisadores comentaram que a relativamente simples escala de Fazekas, em comparação às mais complexas e a método volumétrico, mostrou-se suficiente quando é analisada a relação entre parâmetros clínicos e a carga de HSB em um cenário clínico.

Claudin-1 and Claudin-3 as Molecular Regulators of Myelination in Leukoaraiosis Patients

OBJECTIVES: Leukoaraiosis is described as white matter lesions that are associated with cognitive dysfunction, neurodegenerative disorders, etc. Myelin depletion is a salient pathological feature of, and the loss of oligodendrocytes is one of the most robust alterations evident in, white matter degeneration. Recent studies have revealed that claudin proteins are aberrantly expressed in leukoaraiosis and regulate oligodendrocyte activity. However, the roles of claudin-1 and claudin-3 in oligodendrocytes and leukoaraiosis are still not well-defined. METHODS: Quantitative polymerase chain reaction was used to measure the expression of claudin-1 (CLDN1), claudin-3 (CLDN3), and myelinogenesis-related genes such as myelin basic protein (MBP), proteolipid protein (PLP), oligodendrocyte transcription factor 2 (OLIG2), and SRY-box transcription factor 10 (SOX10) in leukoaraiosis patients (n=122) and healthy controls (n=122). The expression of claudin-1 and claudin-3 was either ectopically silenced or augmented in Oli-neu oligodendrocytes, and colony formation, apoptosis, and migration assays were performed. Finally, the expression of myelin proteins was evaluated by western blotting. RESULTS: Our results revealed that in addition to SOX10, the expression levels of claudin-1, claudin-3, and myelinogenesis-related proteins were prominently downregulated in leukoaraiosis patients, compared to those in healthy controls. Furthermore, the growth and migration of Oli-neu cells were downregulated upon silencing claudin-1 or claudin-3. However, the overexpression of claudin-1 or claudin-3 resulted in the reduction of the degree of apoptosis in Oli-neu cells. In addition, claudin-1 and claudin-3 promoted the expression of MBP, OLIG2, PLP, and SOX10 at the translational level. CONCLUSION: Our data has demonstrated that the abnormal expression of claudin-1 and claudin-3 regulates the pathological progression of leukoaraiosis by governing the viability and myelination of oligodendrocytes. These findings provide novel insights into the regulatory mechanisms underlying the roles of claudin-1 and claudin-3 in leukoaraiosis.

Asymptomatic Cerebral Small Vessel Disease: Insights from Population-Based Studies / 대한뇌졸중학회지

Cerebral small vessel disease (CSVD) is a common group of neurological conditions that confer a significant burden of morbidity and mortality worldwide. In most cases, CSVD is only recognized in its advanced stages once its symptomatic sequelae develop. However, its significance in asymptomatic healthy populations remains poorly defined. In population-based studies of presumed healthy elderly individuals, CSVD neuroimaging markers including white matter hyperintensities, lacunes, cerebral microbleeds, enlarged perivascular spaces, cortical superficial siderosis, and cerebral microinfarcts are frequently detected. While the presence of these imaging markers may reflect unique mechanisms at play, there are likely shared pathways underlying CSVD. Herein, we aim to assess the etiology and significance of these individual biomarkers by focusing in asymptomatic populations at an epidemiological level. By primarily examining population-based studies, we explore the risk factors that are involved in the formation and progression of these biomarkers. Through a critical semi-systematic review, we aim to characterize “asymptomatic” CSVD, review screening modalities, and draw associations from observational studies in clinical populations. Lastly, we highlight areas of research (including therapeutic approaches) in which further investigation is needed to better understand asymptomatic CSVD.

The Effect of Leukoaraiosis on the Severity and Course of Delirium / 정신신체의학

OBJECTIVES: The significance of leukoaraiosis on brain magnetic resonance imaging (MRI) is uncertain, but it is often seen with vascular risk factors or in the context of cognitive impairment. We aimed to investigate the effect of leukoaraiosis on the severity and course of delirium. METHODS: Periventricular hyperintensity and deep white matter hyperintensity on brain MRI were rated in 42 patients with delirium by semiquantative visual rating scale. Correlations between their grades and the scores of Korean version of Delirium Rating Scale-Revised-98 (K-DRS-R-98) were analyzed, and the interaction effects between the groups according to the levels of leukoaraiosis and two evaluation points were also analyzed. RESULTS: The grade of deep white matter hyperintensity in the occipital lobe was positively correlated with the scores on the total, severity items, cognitive items, and non-cognitive items of K-DRS-R-98. The cognitive items scores of K-DRS-R-98 in the low grade group of periventricular hyperintensity showed significantly steeper decrease than the high grade group. CONCLUSIONS: A difference in severity or recovery speed of delirium according to the level of leukoaraiosis may result from disruption in brain functional connectivity. Our results have a clinical implication in that the severity and course of delirium can be possibly predicted using the level of leukoaraiosis.

Lesiones en la sustancia blanca en el paciente anciano: Utilización de la terminología adecuada / White matter lesions in an elderly patient: Using the proper terminology

En Neurorradiología los cambios de la sustancia blanca periventricular o subcortical en pacientes ancianos son descritos generalmente con leucoaraiosis, fenómenos hipóxico-isquémicos crónicos, leucoencefalopatía microangiopática o simplemente con alteraciones en la densidad o intensidad según el método elegido. Sin embargo, ¿es correcto el empleo de estas denominaciones?, ¿funcionan como sinónimos?, ¿tienen un mismo mecanismo de producción? Las lesiones que afectan a la sustancia blanca se aprecian hipodensas en tomografía computada, hiperintensas en las secuencias ponderadas en T2 o FLAIR e hipointensas en la resonancia magnética en ponderación T1. Describimos las distintas entidades que pueden afectar selectivamente la sustancia blanca en el paciente anciano y sus probables mecanismos de acción, para establecer una correcta denominación y realizar los diagnósticos diferenciales.

In Neuroradiology the changes in the deep or sub-cortical white matter in elderly people are generally described as leukoaraiosis, chronic hypoxic-ischaemic processes, microangiopathic leucoencephalopathy, or they are simply mentioned as density or intensity changes according to the selected imaging method. However, are these terms correct?, Are they synonyms?, Do they have the same aetiology? The lesions that affect white matter are hypodense in computed tomography, hyperintense in T2-weighted or FLAIR, or hypointense in T1 images in magnetic resonance. A description is presented on the different conditions that can selectively affect the white matter in the elderly patient and their probable mechanisms of action in order to establish a correct nomenclature, as well as make differential diagnoses.

Association between Leukoaraiosis Severity and Functional Outcomes in Patients with Subcortical Infarct

To investigate the influence of leukoaraiosis (LA) on the functional outcomes of subcortical stroke in the subacute phase after onset. We retrospectively analyzed 41 patients with subacute subcortical infarct at a single center from 2011 to 2015. We explored the relationship between LA severity at admission/transfer (initial evaluation) and functional outcome at the time of discharge (follow-up evaluation), as assessed using the modified Rankin Scale (mRS), Functional Ambulation Category (FAC), and modified Barthel Index (mBI). LA severity was graded as mild, moderate, or severe according to the Fazekas scale. Scores of the mRS, FAC, and mBI were compared in patients grouped based on LA severity: no LA (n = 12), mild LA (n = 19), and moderate-to-severe LA (n = 10). Significant inter-group differences were observed in all 3 scores at both the initial and follow-up evaluations. After adjustment for age, scores at follow-up evaluation were significantly different between the 2 groups. LA is related to functional outcomes of subcortical stroke in the subacute phase after onset. After adjustment for age, severe LA was correlated with poor functional outcomes in the subacute phase.

Regional MRI Diffusion, White-Matter Hyperintensities, and Cognitive Function in Alzheimer's Disease and Vascular Dementia

BACKGROUND AND PURPOSE: An increase in brain water diffusivity as measured using magnetic resonance imaging (MRI) has been recently reported in normal-appearing white matter (NAWM) in patients affected by cognitive impairment. However, it remains to be clarified if this reflects an overt neuronal tissue disruption that leads to degenerative or microvascular lesions. This question was addressed by comparing the regional MRI apparent diffusion coefficients (ADCs) of NAWM in patients affected by Alzheimer's disease (AD) or vascular dementia (VaD). The relationships of ADCs with the white-matter hyperintensity (WMH) burden, carotid atherosclerosis, and cognitive performance were also investigated. METHODS: Forty-nine AD and 31 VaD patients underwent brain MRI to assess the WMH volume and regional NAWM ADCs, neuropsychological evaluations, and carotid ultrasound to assess the plaque severity and intima-media thickness (IMT). RESULTS: Regional ADCs in NAWM did not differ between VaD and AD patients, while the WMH volume was greater in VaD than in AD patients. The ADC in the anterior corpus callosum was related to the WMH volume, while a greater carotid IMT was positively correlated with the temporal ADC and WMH volume. The memory performance was worse in patients with higher temporal ADCs. Constructional praxis scores were related to ADCs in the frontal, and occipital lobes, in the anterior and posterior corpus callosum as well as to the WMH volume. Abstract reasoning was related to frontal, parietal, and temporal ADCs. CONCLUSIONS: Our data show that higher regional ADCs in NAWM are associated with microcirculatory impairment, as depicted by the WMH volume. Moreover, regional ADCs in NAWM are differently associated with the neuropsychological performances in memory, constructional praxia, and abstract reasoning domains.

White Matter Hyperintensity in Ischemic Stroke Patients: It May Regress Over Time / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: White matter hyperintensities (WMH) are frequently observed on MRI in ischemic stroke patients as well as in normal elderly individuals. Besides the progression of WMH, the regression of WMH has been rarely reported. Thus, we aimed to investigate how WMH change over time in patients with ischemic stroke, particularly focusing on regression. METHODS: We enrolled ischemic stroke patients who underwent brain MRI more than twice with at least a 6 month time-interval. Based on T2-weighted or FLAIR MRI, WMH were visually assessed, followed by semiautomatic volume measurement. Progression or regression of WMH change was defined when 0.25 cc increase or decrease was observed and it was also combined with visible change. A statistical analysis was performed on the pattern of WMH change over time and factors associated with change. RESULTS: A total of 100 patients were enrolled. Their age (mean+/-SD) was 67.5+/-11.8 years and 63 were male. The imaging time-interval (mean) was 28.0 months. WMH progressed in 27, regressed in 9 and progressed in distinctive regions and regressed in others in 5 patients. A multiple logistic regression model showed that age (odds ratio[OR] 2.51, 90% confidence interval[CI] 1.056-5.958), male gender (OR 2.957, 95% CI 1.051-9.037), large vessel disease (OR 1.955, 95% CI 1.171-3.366), and renal dysfunction (OR 2.900, 90% CI 1.045-8.046) were associated with progression. Regarding regression, no significant factor was found in the multivariate analysis. CONCLUSIONS: In 21.5% of ischemic stroke patients, regression of WMH was observed. WMH progression was observed in a third of ischemic stroke patients.

White Matter Hyperintensities and Cognitive Dysfunction in Patients With Infratentorial Stroke

OBJECTIVE: To determine whether cognitive function is associated with white matter hyperintensities (WMH) in patients with infratentorial stroke. METHODS: This was a retrospective, cross-sectional study. Twenty-four first-ever infratentorial stroke patients between 18 and 60 years of age were enrolled. WMH was evaluated by the Fazekas scale and the Scheltens scale. Cognitive functions were assessed using the Korean Mini-Mental Status Examination (K-MMSE), Rey-Osterrieth Complex Figure Test, and the Seoul Computerized Neuropsychological Test Battery (SCNT) at one month after stroke. All participants were divided into two groups based on the presence of WMH (no-WMH group and WMH group). General characteristics and cognitive functions were compared between the groups. RESULTS: There were no significant differences in general characteristics, such as age, stroke type, hypertension history, and education level between the two groups. However, K-MMSE in the WMH group was significantly lower compared to the no-WMH group (p<0.05). The verbal learning test score in SCNT was significantly higher in the no-WMH group compared to the WMH group (p<0.05). Executive function in the no-WMH group tended to be higher compared to the WMH group. CONCLUSION: Impairment of cognitive function in patients with infratentorial stroke appeared to be associated with WMH. WMH should be carefully evaluated during rehabilitation of infratentorial stroke patients.

Irregularly shaped lacunar infarction: risk factors and clinical significance / Infartos lacunares com morfologia irregular: fatores de risco e significado clinico

Objective Our study focused on acute lacunar infarct shapes to explore the risk factors and clinical significance of irregularly shaped lacunar infarctions. Methods Based on the shape of their acute lacunar infarct, patients (n=204) were classified into the “regular” group or “irregular” group. The characteristics of the lacunar infarction were compared between the regular and irregular groups, between patients with and without neurological deterioration, and between patients with different modified Rankin scale (mRS) scores. The risk factors for irregularly shaped lacunar infarctions, neurological deterioration, and high mRS scores were identified. Results Blood pressure variability (BPV) was an independent risk factor for irregularly shaped lacunar infarction. Infarction size, prevalence of advanced leukoaraiosis, and irregularly shaped lacunar infarcts were independent risk factors for higher mRS scores. Conclusions The irregularly shaped lacunar infarcts were correlated with BPV. Irregularly shaped lacunar infarctions and leukoaraiosis may be associated with unfavorable clinical outcomes. .

Objetivo Estudar as diferentes formas dos infartos lacunares agudos, investigando os fatores de risco e o significado clinico daqueles com morfologia irregular. Métodos Os 204 pacientes com infartos lacunares agudos foram classificados em dois grupos: aqueles com morfologia regular e aqueles com morfologia irregular. Foram estudadas as características dos dois grupos e caracterizados os fatores de risco para infartos irregulares, deterioração neurológica e altos escores da escala de Rankin modificada. Resultados Variabilidade da pressão arterial é fator de risco independente para infartos lacunares irregulares. Tamanho do infarto, prevalência de leucoaraiose e formato irregular dos infartos lacunares são fatores de risco independentes para escores mais elevados na escala de Rankin modificada. Conclusões Variabilidade da pressão arterial está relacionada ao formato irregular dos infartos lacunares agudos. Este tipo de infarto e a leucoaraiose podem estar relacionado a desfechos clínicos desfavoráveis. .

Comprometimento cognitivo vascular: leucoaraiose, hipocampos e espectroscopia de prótons ? Estudo preliminar / Vascular cognitive impairment: leucoaraiosis, hippocampi, and proton spectroscopy – Preliminary study

Introdução: O continuum do comprometimento cognitivo vascular (CCV) compreende segmento não demência (CCV-ND), segmento demência (CCV-D ou DV), sendo o subtipo mais frequente o CCV subcortical, e inclui, ainda, formas mistas (CCV + DA). Ressonância magnética (RM) do cérebro é o método mais apropriado para avaliação das lesões vasculares, dimensão dos hipocampos e do espectro de prótons (1HMRS). Objetivo: Comparar os valores de metabólitos dos hipocampos (HC) e da região do cíngulo posterior (CP) em grupos de casos de CCV subcortical. Métodos: Casos (n = 55) foram selecionados a partir do banco de dados sobre CCV. Imagens obtidas por equipamento Signa Horizon LX-GE de 1,5T, com protocolo-padrão para aquisição estrutural (incluindo FLAIR, T2 e aquisição para 1H-MRS). Metabólitos estudados (relações) incluíram: Naa/Cr, Co/Cr e mI/Cr. Os casos foram definidos radiologicamente (leucoaraiose grau 3 pela escala de Fazekas modificada) e subdivididos de acordo com a escala de Leon (0-3) em dois em grupos hipocampais (grHC): grHC [0+1] e grHC [2+3]. Análise estatística pelo ANOVA e Tukey. Resultados: A relação Naa/Cr nos HC mostrou diferença significativa entre o grHC [0+1] e o grHC [2+3], o que representa diminuição de integridade (perda) neuronal no segundo, enquanto os CP desses grupos mantiveram os valores estáveis. Houve diferença significativa entre o grHC [2+3] em relação aos CP de ambos os grupos, enquanto o grHC [0+1] ficou compatível com os valores dos CP. Comparação dos valores obtidos em estudos anteriores em CCL e DA mostrou o Naa/Cr com valor intermediário entre os do CCL e da DA nos HC e equivalência de valores nos CP. Conclusão: A 1HMRS possibilita analisar o grau de perda neuronal, além de alterações de membrana e neuroglial dessas regiões. Assim, podem ser obtidas informações para melhor compreender o continuum CCV subcortical (que pode incluir CCV + DA), visando determinar a contribuição dessas duas patologias, caso haja, ao comprometimento cognitivo...

Introduction: Vascular cognitive impairment (VCI) continuum comprisesno-dementia segment (VCI-ND), dementia segment (VCI-D or VaD), with subcortical VCI as the most frequent subtype, and additionally mixed forms (VCI + AD). Magnetic resonance imaging (MRI) of the brain is the most proper method for vascular lesions, hippocampal size, and proton spectrum (1HMRS) assessment. Objective: Comparison of the values of metabolites at the hippocampi (HC) and posterior cingulate (PC) region of groups of cases of subcortical VCI. Methods: Cases (n = 55) were selected from a database on VCI. Images were obtained with Signa Horizon LX-GE de 1.5T equipment and a standard protocol for structural and 1H-MRS acquisitions. Studied metabolites (reasons) were: Naa/Cr, Coh/Cr e mI/Cr. The cases were radiologically defined (grade 3 leucoaraiosis on modified Fazekas scale), and according de Leon?s scale (0-3) subdivided in two hippocampal groups (grHC): grHC[0+1] and grHC[2+3]. Statistical analysis with ANOVA and Tukey. Results: The reason Naa/Cr at the HC showed a significant difference between the grHC[0+1] and grHC[2+3], that represents a reduction of neuronal integrity (loss) in the latter, while at PC these groups maintained stable values. There was a significant difference between grHC [2+3] in relation to PC of both groups, while grHC [0+1] remained compatible with PC values. The comparison of the values obtained from previous studies on MCI and AD showed Naa/Cr with intermediate values between MCI and AD at the HC, and equivalence at the PC. Conclusion: 1HMRS allows for the analysis of the degree of neuronal loss, besides membrane and neuroglial changes of these regions. Thus, information may be obtained for a better understanding of the subcortical VCI continuum (that may include VCI + AD), aiming to determine the contribution of these two pathologies, if present, to the cognitive impairment...

Altered Consciousness After Acute Lacunar Infarction of the Corona Radiata in Patients With Severe White Matter Change

With an increasing proportion of the elderly, dementia due to severe cerebral white matter change is frequently observed. Because these patients cannot express their symptoms effectively, the recognition of stroke can be delayed. In addition, clinical characteristics of their stroke might be different. We reported on three patients with severe leukoaraiosis, who exhibited altered consciousness after acute lacunar infarction in the corona radiata. This clinico-radiological discrepancy may have resulted from different susceptibility to ischemia in patients with severe white matter change.

Study on syndrome factors of leukoaraiosis patients with mild cognitive impairment / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the syndrome factors of leukoaraiosis patients with mild cognitive impairment (LACI), thus providing evidence for syndrome typing.</p><p><b>METHODS</b>The prospective schedule was adopted including 103 LACI patients (as the LACI group) and 100 leukoaraiosis patients without mild cognitive impairment (as the control group). Syndrome factors were extracted from the patients' symptoms with frequency statistics and factor analysis.</p><p><b>RESULTS</b>Fifteen common factors were extracted from the LACI group, and 12 common factors from the control group. After analyzed the distribution of syndrome factors in the LACI group, the most common factors were ranked as follows: yang deficiency (33.98%), phlegm (22.33%), yin deficiency (19.42%), qi deficiency (10.68%), fire (9.71%), blood deficiency and blood stasis (3.88%). As for the control group, the most common factors were ranked as follows: yang deficiency (31.00%), qi deficiency (27.00%), yin deficiency and fire (24.00%), blood deficiency and blood stasis (12.00%), phlegm and yang deficiency and blood deficiency (6.00%).</p><p><b>CONCLUSIONS</b>The main syndrome factors of LACI were yang deficiency, phlegm, yin deficiency, and fire. The secondary syndrome factors were qi deficiency, blood deficiency, and blood stasis. It was mainly involved with Shen and Pi, with secondary organs as Gan and Xin. Deficiency syndrome is its pathogenesis. Phlegm and fire, and other pathological factors are essential for its development and aggravation, with more syndrome factors accompanied in complex condition.</p>

Ischemic Stroke in Patients with Renal Transplantation / 대한뇌졸중학회지

BACKGROUND: Impaired renal function may contribute to development of stroke and small vessel pathology in the brain. We investigated whether stroke subtype, initial stroke severity, early neurologic outcomes, time to cerebral infarction occurrence, and the presence of small vessel pathology in the brain are different between patients with end stage renal disease (ESRD) and those with renal transplantation (RT). METHODS: A total of 57 consecutive de novo RT patients (RT group) and 120 patients undergoing dialysis due to ESRD (ESRD group) who developed a first-ever acute cerebral infarction were enrolled. We compared stroke subtypes based on the Trial of Org 10172 in Acute Stroke Treatment classification, the presence of small vessel pathology (cerebral microbleed, leukoaraiosis and silent lacunar infarction) on MRI, stroke severity based on the National Institutes of Health Stroke Scale (NIHSS) and in-hospital mortality between the groups. RESULTS: The stroke subtypes, NIHSS scores at admission and in-hospital mortality were not different between the two groups. On multivariate analysis, the presence of high grade periventricular white matter changes tended to be more frequently detected in the ESRD group than the RT (P=0.078). The time from starting dialysis to stroke was longer in the RT group (129.9+/-60.9 months) than in the ESRD group (51.1+/-46.1 months). CONCLUSIONS: The stroke patterns, severity and short term outcomes were not different between RT and ESRD. The risk of cerebral infarction and high grade periventricular white matter changes may be reduced after RT in patients with ESRD.

Vascular Endothelial Dysfunction in Cerebral Leukoaraiosis

BACKGROUND: Chronic subclinical ischemia has been considered as one of major causes of leukoaraiosis, although its trigger is unknown. The vascular endothelium plays a major role in maintaining cerebral perfusion through autoregulation. In this study we evaluated the endothelial bioavailability of nitric oxide (NO) in patients with leukoaraiosis. METHODS: We enrolled consecutive patients with lacunar syndrome or transient ischemic attack; the control group comprised age- and sex-matched patients with hypertension but with no neurological abnormality. All participants underwent flow-mediated dilatation of the brachial artery (FMD) to evaluate endothelial function. Leukoaraiosis was defined as ill-defined patches with high signal intensities on FLAIR and low signal intensities on T1-weighted images. Patients were defined as having ischemic leukoaraiosis if they presented with leukoaraiosis and lacunar infarction. Leukoaraiosis only was defined when patient had leukoaraiosis without lacunar infarction leukoaraiosis without lacunar infarction. RESULTS: In total, 75 patients (37 with leukoaraiosis and 38 controls) were enrolled in this study. The demographic and clinical characteristics were similar in the two groups. FMD was lower in patients with leukoaraiosis than in controls (p0.05). CONCLUSIONS: The bioavailability of NO in the vascular endothelium is decreased in patients with leukoaraiosis only and in those who also have ischemic leukoaraiosis compared to controls. These results are suggestive of a causative role of endothelial dysfunction in the pathomechanism of leukoaraiosis.

Vascular Dementia / 전남의대학술지

Cerebrovascular disease is the second leading cause of cognitive impairment in the elderly, either alone or in combination with Alzheimer's disease (AD). Vascular dementia (VaD) is heterogeneous in terms of both clinical phenotype and pathogenetic mechanisms. It may result from multiple cortical infarctions due to cerebral large vessel pathologies or to subcortical ischemic changes such as leukoaraiosis or lacunar infarction due to cerebral small artery disease. Clinical symptoms and signs vary depending on the location and size of the stroke lesion, and no single neuropsychological profile characteristic of VaD has been defined, although dysexecutive function is common. A slightly higher mortality rate and slower progression are reported in VaD compared with AD. VaD is potentially preventable by rigorous identification and treatment of cardiovascular disease risk factors, and modest symptomatic improvement with cholinesterase inhibitors has been reported.

Vascular Dementia / 전남의대학술지

Cerebrovascular disease is the second leading cause of cognitive impairment in the elderly, either alone or in combination with Alzheimer's disease (AD). Vascular dementia (VaD) is heterogeneous in terms of both clinical phenotype and pathogenetic mechanisms. It may result from multiple cortical infarctions due to cerebral large vessel pathologies or to subcortical ischemic changes such as leukoaraiosis or lacunar infarction due to cerebral small artery disease. Clinical symptoms and signs vary depending on the location and size of the stroke lesion, and no single neuropsychological profile characteristic of VaD has been defined, although dysexecutive function is common. A slightly higher mortality rate and slower progression are reported in VaD compared with AD. VaD is potentially preventable by rigorous identification and treatment of cardiovascular disease risk factors, and modest symptomatic improvement with cholinesterase inhibitors has been reported.

Leukoaraiosis on Magnetic Resonance Imaging Is Related to Long-Term Poor Functional Outcome after Thrombolysis in Acute Ischemic Stroke

OBJECTIVE: Leukoaraiosis (LA) has been suggested to be related to the poor outcome or the occurrence of symptomatic intracerebral hemorrhage (sICH) after acute ischemic stroke. We retrospectively investigated the influences of LA on long-term outcome and the occurrence of sICH after thrombolysis in acute ischemic stroke (AIS). METHODS: In this study, we recruited 164 patients with AIS and magnetic resonance image (MRI)-detected thrombolysis. The presence and extent of LA were assessed using the Fazekas grading system. The National Institutes of Health Stroke Scale score was used to assess the baseline measure of neurologic severity, and the modified Rankin Scale score assessment was used up to 1 year after thrombolysis. RESULTS: Of 164 subjects, 56 (34.2%) showed LA on MRI. Compared to the 108 patients without LA, the patients with LA were of much older age (p<0.01), had a higher prevalence of hypertension (p<0.01), and had a much poorer outcome at 90 days (p=0.05) and 1 yr (p=0.01) after thrombolysis. There were no significant differences in sICH between patients with and without LA on MRI. In univariate analysis for the occurrence of poor outcome at 90 days after thrombolysis, the size of ischemic lesion on diffusion weighted images (DWI), [odds ratio (OR), 1.03; 95% confidence interval (95% CI), 1.01-1.04; p<0.01], recanalization (OR, 0.03; 95% CI, 0.01-0.10; p<0.01), sICH (OR, 12.2; 95% CI, 1.54-95.8), neurologic severity (OR, 1.17; 95% CI, 1.09-1.25; p<0.01), blood glucose level (OR, 1.01; 95% CI, 1.00-1.02; p=0.03), and the presence of LA on MRI (OR, 2.01; 95% CI, 1.04-3.01; p=0.04) were statistically significant. In multivariate analysis, neurologic severity (OR, 1.14; 95% CI, 1.04-1.24; p<0.01), recanalization (OR, 0.03; 95% CI, 0.01-0.11; p<0.01), lesion size on DWI (OR, 1.02; 95% CI, 1.01-1.03; p=0.02), serum glucose level (OR, 1.01; 95% CI; 1.01-1.02; p=0.03), and the presence of LA on MRI (OR, 3.2; 95% CI, 1.22-8.48; p<0.01) showed statistically significant differences. These trends persisted up to 1 yr after thrombolysis. CONCLUSION: In this study, we demonstrated that the presence of LA on MRI might be related to poor outcome after use of intravenous tissue plasminogen activator in AIS.

Correlation between diffusion anisotropy of the white matter fibers and cognitive function in patients with leukoaraiosis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the correlation between the diffusion anisotropy of the white matter fibers and the cognitive function in patients with leukoaraiosis (LA).</p><p><b>METHODS</b>Thirty-one LA patients were enrolled in this study, including 13 with grade LA-1 (mild), 12 with grade LA-2 (moderate) and 6 with grade LA-3 (severe) condition. The control group consisted of 18 subjects who were free of obvious clinical symptoms or had only mild dizziness and headache but with negative history for neural system diseases and in the absence of cognitive dysfunction, brain trauma, positive signs in neurological examinations, or abnormities in MRI examination. The Mini-mental State Examination (MMSE) was applied to evaluate the patients' cognitive function. The LA patients underwent examination with diffusion tensor MR imaging (DTI), and the FA and MD values in the normal-appearing white matter (NAWM) were measured.</p><p><b>RESULTS</b>The cognitive function of the LA patients tended to decline with the decrease of the MMSE scores, and their scores for time orientation, place orientation and calculation were significantly lower than those of the control group (P<0.05). No significant difference was found in memory, language and comprehensive abilities between the LA and control groups. In LA-1, LA-2 and total LA cases, the FA value in the NAWM was positively, and the MD value inversely, correlated to the cognitive function with correlation coefficients ranging from 0.5 to 0.8 (P<0.05).</p><p><b>CONCLUSION</b>The DTI parameters of NAWM region are correlated to the cognitive function of LA patients. DTI is far more sensitive than MRI in evaluating cognitive dysfunction in LA patients.</p>