Deep learning-based white matter lesion volume on CT is associated with outcome after acute ischemic stroke.

BACKGROUND: Intravenous thrombolysis (IVT) before endovascular treatment (EVT) for acute ischemic stroke might induce intracerebral hemorrhages which could negatively affect patient outcomes. Measuring white matter lesions size using deep learning (DL-WML) might help safely guide IVT administration. We aimed to develop, validate, and evaluate a DL-WML volume on CT compared to the Fazekas scale (WML-Faz) as a risk factor and IVT effect modifier in patients receiving EVT directly after IVT. METHODS: We developed a deep-learning model for WML segmentation on CT and validated with internal and external test sets. In a post hoc analysis of the MR CLEAN No-IV trial, we associated DL-WML volume and WML-Faz with symptomatic-intracerebral hemorrhage (sICH) and 90-day functional outcome according to the modified Rankin Scale (mRS). We used multiplicative interaction terms between WML measures and IVT administration to evaluate IVT treatment effect modification. Regression models were used to report unadjusted and adjusted common odds ratios (cOR/acOR). RESULTS: In total, 516 patients from the MR CLEAN No-IV trial (male/female, 291/225; age median, 71 [IQR, 62-79]) were analyzed. Both DL-WML volume and WML-Faz are associated with sICH (DL-WML volume acOR, 1.78 [95%CI, 1.17; 2.70]; WML-Faz acOR, 1.53 95%CI [1.02; 2.31]) and mRS (DL-WML volume acOR, 0.70 [95%CI, 0.55; 0.87], WML-Faz acOR, 0.73 [95%CI 0.60; 0.88]). Only in the unadjusted IVT effect modification analysis WML-Faz was associated with more sICH if IVT was given (p = 0.046). Neither WML measure was associated with worse mRS if IVT was given. CONCLUSION: DL-WML volume and WML-Faz had a similar relationship with functional outcome and sICH. Although more sICH might occur in patients with more severe WML-Faz receiving IVT, no worse functional outcome was observed. CLINICAL RELEVANCE STATEMENT: White matter lesion severity on baseline CT in acute ischemic stroke patients has a similar predictive value if measured with deep learning or the Fazekas scale. Safe administration of intravenous thrombolysis using white matter lesion severity should be further studied. KEY POINTS: White matter damage is a predisposing risk factor for intracranial hemorrhage in patients with acute ischemic stroke but remains difficult to measure on CT. White matter lesion volume on CT measured with deep learning had a similar association with symptomatic intracerebral hemorrhages and worse functional outcome as the Fazekas scale. A patient-level meta-analysis is required to study the benefit of white matter lesion severity-based selection for intravenous thrombolysis before endovascular treatment.

Risk Factors and Clinical Characteristics of First-ever Ischemic Stroke Caused by ICAS with Leukoaraiosis.

Background: Previous studies have mostly investigated the risk factors affecting the occurrence of leukoaraiosis and the risk factors affecting the severity of leukoaraiosis in patients with ischemic stroke, but there are relatively few studies on the risk factors and clinical characteristics affecting the severity of leukoaraiosis in the population with the most common type of first-episode ischemic stroke caused by intracranial atherosclerotic stenosis in China. Methods: We retrospectively studied patients with first-ever ischemic stroke due to intracranial atherosclerotic stenosis. All patients underwent diffusion weight magnetic resonance imaging and adjunctive examinations such as magnetic resonance angiography and/or computed tomography angiography and/or digital subtraction angiography. The characteristics and clinical data were also statistically analyzed. Results: Of the 504 patients enrolled, 176 (34.92%), 202 (40.08%), and 126 (25.00%) patients were in the mild, moderate, and severe groups, respectively, and the patients were older in the severe group compared with the moderate and mild groups (p < 0.05). Hypertension was more severe in the severe group compared with the severe and mild groups (p < 0.05). The time to hospital admission was shorter in the severe group compared with the moderate and mild groups (p < 0.05). The admission National Institutes of Health stroke scale was higher in the severe group than in the moderate and mild groups (p < 0.05). homocysteine, glucose, glycohemoglobin A1c, neutrophil-lymphocyte ratio, and ultrasensitive C-reactive protein to albumin ratio levels were significantly different between the three groups (p < 0.05). There was no significant correlation between the distribution of infarct foci in the anterior and posterior circulation in the three groups (p > 0.05). Conclusion: Age and homocysteine were independent risk factors for leukoaraiosis severity in patients with acute ischemic stroke, and all were positively associated with leukoaraiosis severity. Hypertension, glucose, glycohemoglobin A1c, neutrophil-lymphocyte ratio and ultrasensitive C-reactive protein to albumin ratio levels were highly significant in evaluating the prognosis of patients.

Feasibility of CT attenuation values in distinguishing acute ischemic stroke, old cerebral infarction and leukoaraiosis.

PURPOSE: This study aimed to investigate the feasibility of using computed tomography (CT) attenuation values to differentiate hypodense brain lesions, specifically acute ischemic stroke (AIS) from asymmetric leukoaraiosis (LA) and old cerebral infarction (OCI). MATERIALS AND METHODS: This retrospective study included patients with indeterminate hypodense lesions identified via brain CT scans conducted between June 2019 and June 2021. All lesions were confirmed through head MRI/diffusion-weighted imaging within 48 h after CT. CT attenuation values of hypodense lesions and symmetrical control regions were measured. Additionally, CT attenuation value difference (ΔHU) and ratio (RatioHU) were calculated. One-way analysis of variance (ANOVA) was used to compare age and CT parameters (CT attenuation values, ΔHU and RatioHU) across the groups. Finally, receiver operating characteristic (ROC) analysis was performed to determine the cutoff values for distinguishing hypodense lesions. RESULTS: A total of 167 lesions from 146 patients were examined. The CT attenuation values for AIS(n = 39), LA(n = 53), and OCI(n = 75) were 18.90 ± 6.40 HU, 17.53 ± 4.67 HU, and 11.90 ± 5.92 HU, respectively. The time interval between symptom onset and CT scans for AIS group was 32.21 ± 26.85 h. ANOVA revealed significant differences among the CT parameters of the hypodense lesion groups (all P < 0.001). The AUC of CT values, ΔHU, and RatioHU for distinguishing AIS from OCI were 0.802, 0.896 and 0.878, respectively (all P < 0.001). Meanwhile, the AUC for distinguishing OCI from LA was 0.789, 0.883, and 0.857, respectively (all P < 0.001). Nevertheless, none of the parameters could distinguish AIS from LA. CONCLUSION: CT attenuation parameters can be utilized to differentiate between AIS and OCI or OCI and LA in indeterminate hypodense lesions on CT images. However, distinguishing AIS from LA remains challenging.

Leukoaraiosis in patients with tirofiban before endovascular thrombectomy: A post hoc analysis of a multicentre randomized clinical trial.

BACKGROUND AND PURPOSE: To evaluate the effectiveness and safety of intravenous tirofiban before endovascular thrombectomy in subgroups of acute ischemic stroke patients with different degrees of leukoaraiosis (LA). METHODS: Patients of the RESCUE BT trial whose LA grade could be assessed were included. Eligible patients were dichotomized into two strata according to the van Swieten scale (VSS) score, absent-to-moderate LA (VSS score <3) and severe LA (VSS score ≥3). Furthermore, patients were divided into tirofiban and placebo groups in each stratum. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Safety outcome was radiological intracranial hemorrhage within 48 h. RESULTS: 861 patients were included, 439 patients with absent-to-moderate LA and 422 patients with severe LA. There were no significant differences in 90-day mRS score between the tirofiban and placebo groups in either stratum (absent-to-moderate LA: adjusted OR 0.92 (95%CI, 0.66-1.28), P = 0.62; severe LA: adjusted OR 0.99 (95% CI, 0.69-1.42), P = 0.96). In the severe LA stratum, the occurrence of radiologic intracranial hemorrhage was greater in the tirofiban group compared to the placebo group. (35.7% vs 26.4%; adjusted OR, 1.72 (95% CI, 1.12-2.66); P = 0.014). However, no difference was observed in the absent-to-moderate LA stratum (33.2% vs 29.3%; adjusted OR, 1.15 (95% CI, 0.76-1.75); P = 0.51). CONCLUSION: There was no significant difference in disability severity at 90 days when treating AIS patients using intravenous tirofiban before endovascular therapy, in either absent-to-moderate or severe LA strata. It should be noted that intravenous tirofiban before endovascular therapy increases the incidence of radiologic intracranial hemorrhage in patients with severe LA.

Characteristics of brain lesions found using MRI imaging in patients with post-COVID with signs of cognitive decline.

OBJECTIVE: Aim: To describe and evaluate abnormalities of the brain in post-COVID patients with neurologic symptoms and cognitive deficits using MRI imaging of the brain. PATIENTS AND METHODS: Materials and Methods: We included 21 patients with a previous positive PCR testing for SARS-CoV-2 and one or more of the following symptoms: memory and cognitive decline, dizziness, anxiety, depression, chronic headaches. All patients had MRI imaging done at onset of symptoms, but after at least 1 year after positive testing for COVID-19 based on the patient's previous medical history. RESULTS: Results: All of the patients complained of lack of concentration, forgetfulness, hard to process information. 15 patients suffered from confusion, 10 from anxiety. Of the 21 patients 14 had isolated chronic headaches, 3 had isolated dizziness, 4 patients had both symptoms upon inclusion. All patients underwent MRI imaging as a part of the diagnostic workup and had varying degrees of neurodegeneration. CONCLUSION: Conclusions: Our data correlates with existing research and shows tendency for cognitive decline in post-COVID patients. This provides groundwork for further research to determine correlation between acceleration of neurodegeneration and post-COVID.

The Neurovasculome: Key Roles in Brain Health and Cognitive Impairment: A Scientific Statement From the American Heart Association/American Stroke Association.

BACKGROUND: Preservation of brain health has emerged as a leading public health priority for the aging world population. Advances in neurovascular biology have revealed an intricate relationship among brain cells, meninges, and the hematic and lymphatic vasculature (the neurovasculome) that is highly relevant to the maintenance of cognitive function. In this scientific statement, a multidisciplinary team of experts examines these advances, assesses their relevance to brain health and disease, identifies knowledge gaps, and provides future directions. METHODS: Authors with relevant expertise were selected in accordance with the American Heart Association conflict-of-interest management policy. They were assigned topics pertaining to their areas of expertise, reviewed the literature, and summarized the available data. RESULTS: The neurovasculome, composed of extracranial, intracranial, and meningeal vessels, as well as lymphatics and associated cells, subserves critical homeostatic functions vital for brain health. These include delivering O2 and nutrients through blood flow and regulating immune trafficking, as well as clearing pathogenic proteins through perivascular spaces and dural lymphatics. Single-cell omics technologies have unveiled an unprecedented molecular heterogeneity in the cellular components of the neurovasculome and have identified novel reciprocal interactions with brain cells. The evidence suggests a previously unappreciated diversity of the pathogenic mechanisms by which disruption of the neurovasculome contributes to cognitive dysfunction in neurovascular and neurodegenerative diseases, providing new opportunities for the prevention, recognition, and treatment of these conditions. CONCLUSIONS: These advances shed new light on the symbiotic relationship between the brain and its vessels and promise to provide new diagnostic and therapeutic approaches for brain disorders associated with cognitive dysfunction.

Effect of leukoaraiosis on collateral circulation in acute ischemic stroke treated with endovascular therapy: a meta-analysis.

BACKGROUND AND OBJECTIVE: The recruitment of collateral circulation correlates with a balance of the microvasculature. Uncertainty remains to be made about the association of leukoaraiosis with leptomeningeal collaterals. To explore the effect of leukoaraiosis on leptomeningeal collaterals in patients treated with endovascular therapy. METHODS: Observational studies exploring the correlation between leukoaraiosis and leptomeningeal collaterals in large vessel occlusion treated with endovascular therapy were searched from PubMed, EMBASE, and Cochrane Libraries databases. Two independent reviewers retrieved eligible literature, extracted purpose-related data, and utilized the Newcastle-Ottawa Scale to evaluate the risk of bias. A Mantel-Haenszel method was used to calculate the odds ratio (OR). Meta-regression and subgroup analyses were conducted to clarify heterogeneity. RESULTS: Data from 10 studies with 1606 patients were extracted for pooled analysis. Compared to non-severe leukoaraiosis, patients with severe leukoaraiosis showed significant relevance to poor leptomeningeal collaterals (OR, 2.13; 95% confidence interval [1.27-3.57]; P = 0.004). Meta-regression indicated that sample size (coefficient = -0.007299, P = 0.035) and the number of female patients (coefficient = -0.0174709, P = 0.020) were sources of heterogeneity. Furthermore, all of the countries (USA versus France versus China, Q = 3.67, P = 0.159), various assessment scales of leukoaraiosis (the Fazekas scale versus Non-Fazekas scales, Q = 0.77, P = 0.379), and different imaging methods of leukoaraiosis (computed tomography versus magnetic resonance imaging, Q = 2.12, P = 0.146) and leptomeningeal collaterals (computed tomography angiography versus digital subtraction angiography, Q = 1.21, P = 0.271) showed no contribution to the effect size. CONCLUSION: Severe leukoaraiosis is associated with poor leptomeningeal collaterals in patients treated with endovascular therapy. Further studies may focus on whether the finding applies to different stroke subtypes.

Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism and the Risk of Leukoaraiosis in a South Chinese Han Population: A Case-Control Study.

Leukoaraiosis (LA) appears as white matter hyperintensities on T2-weighted brain magnetic resonance imaging scans. Age and hypertension are considered the primary risk factors for LA, but its pathogenesis remains uncertain. This study aims to investigate the correlation between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and LA. A total of 140 patients with LA and 136 neuroimaging alteration-free controls were recruited in a case-control study. ACE I/D polymorphism was determined using the polymerase chain reaction method. The allele and genotype distributions of the ACE I/D polymorphism were significantly different between subjects with and without LA. Significant difference was observed in the genotypic distribution between LA patients and controls for recessive and additive models. A statistically significant association remained apparent after adjusting for potential risk factors (D/D vs. I/D + I/I: adjusted OR 3.251, 95% CI 1.185-8.918; D/D vs. I/I: adjusted OR 3.277, 95% CI 1.187-9.047). Our results indicate that the D/D genotype and D allele are important risk factors for LA. Future studies with larger populations are needed to validate our results.

Vitamin E reduces inflammation and improves cognitive disorder and vascular endothelial functions in patients with leukoaraiosis.

BACKGROUND: Leukoaraiosis (LA) is a disease manifested by demyelination and gliosis in white matter, mainly caused by cerebrovascular diseases. LA is closely related to the expression level of inflammatory factors, oxidative stress, and vascular endothelial dysfunction in patients. Vitamin E may play antioxidant and anti-inflammatory roles in various diseases. We aimed to explore the effects of vitamin E on the patients with LA. METHODS: A total of 160 patients with LA were recruited in this research. Matrix metalloproteinase-9 (MMP-9), MMP-2, C-reactive protein (CRP), complement 3 (C3), C4, nitric oxide (NO), and endothelin (ET) levels were evaluated by ELISA. The Mini-Mental State Examination (MMSE) was used for cognitive impairment assessment. Superoxide dismutase (SOD) and malondialdehyde (MDA) concentrations were analyzed by commercial kits. RESULTS: The levels of CRP, C3, and C4 significantly decreased in the serum of LA patients after the administration of vitamin E. The levels of MMP-2 and MPP-9 showed a significant decrease in the administered group. Vitamin E significantly inhibited the expression of MDA, while significantly upregulated the expression of SOD. Significant increase in NO production and significant downregulation of ET expression occurred in vitamin E groups. MMSE score was significantly increased by vitamin E. CONCLUSION: In conclusion, vitamin E showed effects on the alleviation of inflammatory response, oxidative stress, endothelial damage, and cognitive dysfunction. Thus, vitamin E could be a potential drug for the clinical treatment of LA patients.

PECULIARITIES OF STRUCTURAL CHANGES IN THE BRAIN SUBSTANCE IN PATIENTS WITH ARRHYTHMIAS DEPENDING ON THE SEVERITY OF COGNITIVE DISORDERS.

OBJECTIVE: The aim: To evaluate the structural changes of the brain in relation to the formation of cognitive disorders (CD) in patients with arrhythmias. PATIENTS AND METHODS: Materials and methods: 147 patients with different clinical forms arrhythmias against the background of ischemic heart disease were examine. At the first stage, all patients with arrhythmias assessed cognitive functions. At the second stage, patients were distributed divided into two groups: the main group patients with CD, control - patients without CD. These groups underwent computed tomography examination of the brain. RESULTS: Results: CD were established in 83% patients with arrhythmias. Mild CD were more often diagnosed in patients with persistent form of atrial fibrillation (AF), severe CD - in patients with permanent form of AF and atrioventricular blockade ІI-III degrees. Neuroimaging changes were found in 73.8% patients with CD and in 36% patients without CD. They were manifested by atrophic changes of the cortex, internal hydrocephalus, a decrease in the density of the brain sub¬stance of the periventricular area. In patients with CD, compared to patients without CD, showed lacunar foci with predominant localization in the parietal and frontal lobes of the brain, periventricular and subcortical leukoaraiosis. Multiple correlations were established between CD and structural changes of the brain. CONCLUSION: Conclusions: The increase in the severity of CD in patients with arrhythmias is associated with atrophic changes at the cortical-subcortical level, accompanied by the phenomena of internal hydrocephalus, periventricular and subcortical LA, lacunar foci, with a predominant localization in the frontal-temporal-occipital lobes, in the visual hump and basal ganglia of both cerebral hemispheres.

Rho-Kinase Inhibition Improves the Outcome of Focal Subcortical White Matter Lesions.

BACKGROUND: Subcortical white matter lesions are exceedingly common in cerebral small vessel disease and lead to significant cumulative disability without an available treatment. Here, we tested a rho-kinase inhibitor on functional recovery after focal white matter injury. METHODS: A focal corpus callosum lesion was induced by stereotactic injection of N5-(1-iminoethyl)-L-ornithine in mice. Fasudil (10 mg/kg) or vehicle was administered daily for 2 weeks, starting one day after lesion induction. Resting-state functional connectivity and grid walk performance were studied longitudinally, and lesion volumes were determined at one month. RESULTS: Resting-state interhemispheric functional connectivity significantly recovered between days 1 and 14 in the fasudil group (P<0.001), despite worse initial connectivity loss than vehicle before treatment onset. Grid walk test revealed an increased number of foot faults in the vehicle group compared with baseline, which persisted for at least 4 weeks. In contrast, the fasudil arm did not show an increase in foot faults and had smaller lesions at 4 weeks. Immunohistochemical examination of reactive astrocytosis, synaptic density, and mature oligodendrocytes did not reveal a significant difference between treatment arms. CONCLUSIONS: These data show that delayed fasudil posttreatment improves functional outcomes after a focal subcortical white matter lesion in mice. Future work will aim to elucidate the mechanisms.

Aortic Stiffness, Pulse Pressure, and Cerebral Pulsatility Progress Despite Best Medical Management: The OXVASC Cohort.

BACKGROUND: Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. METHODS: In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), arterial stiffness (pulse wave velocity [PWV]) and aortic systolic, aortic diastolic, and aortic pulse pressures (aoPP) were measured by applanation tonometry (Sphygmocor), while middle cerebral artery (MCA) peak (MCA-PSV) and trough (MCA-EDV) flow velocity and Gosling pulsatility index (PI; MCA-PI) were measured by transcranial ultrasound (transcranial Doppler, DWL Doppler Box). Repeat assessments were performed at the 5-year follow-up visit after intensive medical treatment and agreement determined by intraclass correlation coefficients. Rates of progression and their determinants, stratified by age and sex, were determined by mixed-effects linear models, adjusted for age, sex, and cardiovascular risk factors. RESULTS: In 188 surviving, eligible patients with repeat assessments after a median of 5.8 years. PWV, aoPP, and MCA-PI were highly reproducible (intraclass correlation coefficients, 0.71, 0.59, and 0.65, respectively), with progression of PWV (2.4%; P<0.0001) and aoPP (3.5%; P<0.0001) but not significantly for MCA-PI overall (0.93; P=0.22). However, PWV increased at a faster rate with increasing age (0.009 m/s per y/y; P<0.0001), while aoPP and MCA-PI increased significantly above the age of 55 years (aoPP, P<0.0001; MCA-PI, P=0.009). Higher aortic systolic blood pressure and diastolic blood pressure predicted a greater rate of progression of PWV and aoPP, but not MCA-PI, although current MCA-PI was particularly strongly associated with concurrent aoPP (P<0.001). CONCLUSIONS: Arterial pulsatility and aortic stiffness progressed significantly after 55 years of age despite the best medical treatment. Progression of stiffness and aoPP was determined by high blood pressure, but MCA-PI predominantly reflected current aoPP. Treatments targetting cerebral pulsatility may need to principally target aortic stiffness and pulse pressure to have the potential to prevent cerebral small vessel disease.

Oxygen Metabolic Stress and White Matter Injury in Patients With Cerebral Small Vessel Disease.

BACKGROUND: Chronic hypoxia-ischemia is a putative mechanism underlying the development of white matter hyperintensities (WMH) and microstructural disruption in cerebral small vessel disease. WMH fall primarily within deep white matter (WM) watershed regions. We hypothesized that elevated oxygen extraction fraction (OEF), a signature of hypoxia-ischemia, would be detected in the watershed where WMH density is highest. We further hypothesized that OEF would be elevated in regions immediately surrounding WMH, at the leading edge of growth. METHODS: In this cross-sectional study conducted from 2016 to 2019 at an academic medical center in St Louis, MO, participants (age >50) with a range of cerebrovascular risk factors underwent brain magnetic resonance imaging using pseudocontinuous arterial spin labeling, asymmetric spin echo, fluid-attenuated inversion recovery and diffusion tensor imaging to measure cerebral blood flow (CBF), OEF, WMH, and WM integrity, respectively. We defined the physiologic watershed as a region where CBF was below the 10th percentile of mean WM CBF in a young healthy cohort. We conducted linear regression to evaluate the relationship between CBF and OEF with structural and microstructural WM injury defined by fluid-attenuated inversion recovery WMH and diffusion tensor imaging, respectively. We conducted ANOVA to determine if OEF was increased in proximity to WMH lesions. RESULTS: In a cohort of 42 participants (age 50-80), the physiologic watershed region spatially overlapped with regions of highest WMH lesion density. As CBF decreased and OEF increased, WMH density increased. Elevated watershed OEF was associated with greater WMH burden and microstructural disruption, after adjusting for vascular risk factors. In contrast, WM and watershed CBF were not associated with WMH burden or microstructural disruption. Moreover, OEF progressively increased while CBF decreased, in concentric contours approaching WMH lesions. CONCLUSIONS: Chronic hypoxia-ischemia in the watershed region may contribute to cerebral small vessel disease pathogenesis and development of WMH. Watershed OEF may hold promise as an imaging biomarker to identify individuals at risk for cerebral small vessel disease progression.

Risk Factors, Lifestyle Behaviors, and Vascular Brain Health.

Although a relationship between traditional cardiovascular risk factors and stroke has long been recognized, these risk factors likely play a role in other aspects of brain health. Clinical stroke is only the tip of the iceberg of vascular brain injury that includes covert infarcts, white matter hyperintensities, and microbleeds. Furthermore, an individual's risk for not only stroke but poor brain health includes not only these traditional vascular risk factors but also lifestyle and genetic factors. The purpose of this narrative review is to summarize the state of the evidence on traditional and nontraditional vascular risk factors and their contributions to brain health. Additionally, we will review important modifiers that interact with these risk factors to increase, or, in some cases, reduce risk of adverse brain health outcomes, with an emphasis on genes and biomarkers associated with Alzheimer disease. Finally, we will consider the importance of social determinants of health in brain health outcomes.

Incidence of white matter lesions in hospitalized COVID-19 patients: A meta-analysis.

OBJECTIVE: Novel coronavirus disease 2019 (COVID-19) has been found to be associated with encephalopathy and brain imaging abnormalities. The identification of incident white matter lesions, known to be associated with cerebral microcirculatory failure and cerebrovascular disease, in COVID-19 patients is of clinical and scientific interest. We performed a meta-analysis to investigate the incidence of white matter lesions (WMLs) in hospitalized COVID-19 patients. METHODS: PubMed, EMBASE, and the Cochrane Library were searched for studies on brain imaging abnormalities in hospitalized COVID-19 patients. The terms used included "white matter lesions," "white matter hyperintensity," "COVID-19," "coronavirus," and "SARS-CoV-2." A random-effects meta-analysis was conducted to obtain a pooled estimate of WML prevalence in hospitalized COVID-19 patients. RESULTS: A total of 4 eligible studies involving 362 patients (144 with WMLs and 218 without) were included in the meta-analysis. We found the pooled estimate of WML prevalence to be 20% (ES 0.20; 95% CI 0.00-0.54; p = .03). CONCLUSIONS: The estimated pooled prevalence rate of WMLs was approximately 20% in hospitalized COVID-19 patients, albeit lower than the crude prevalence rate (39.8%).

Risk factors analysis according to regional distribution of white matter hyperintensities in a stroke cohort.

OBJECTIVES: The spectrum of distribution of white matter hyperintensities (WMH) may reflect different functional, histopathological, and etiological features. We examined the relationships between cerebrovascular risk factors (CVRF) and different patterns of WMH in MRI using a qualitative visual scale in ischemic stroke (IS) patients. METHODS: We assembled clinical data and imaging findings from patients of two independent cohorts with recent IS. MRI scans were evaluated using a modified visual scale from Fazekas, Wahlund, and Van Swieten. WMH distributions were analyzed separately in periventricular (PV-WMH) and deep (D-WMH) white matter, basal ganglia (BG-WMH), and brainstem (B-WMH). Presence of confluence of PV-WMH and D-WMH and anterior-versus-posterior WMH predominance were also evaluated. Statistical analysis was performed with SPSS software. RESULTS: We included 618 patients, with a mean age of 72 years (standard deviation [SD] 11 years). The most frequent WMH pattern was D-WMH (73%). In a multivariable analysis, hypertension was associated with PV-WMH (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.29-2.50, p = 0.001) and BG-WMH (OR 2.13, 95% CI 1.19-3.83, p = 0.012). Diabetes mellitus was significantly related to PV-WMH (OR 1.69, 95% CI 1.24-2.30, p = 0.001), D-WMH (OR 1.46, 95% CI 1.07-1.49, p = 0.017), and confluence patterns of D-WMH and PV-WMH (OR 1.62, 95% CI 1.07-2.47, p = 0.024). Hyperlipidemia was found to be independently related to brainstem distribution (OR 1.70, 95% CI 1.08-2.69, p = 0.022). CONCLUSIONS: Different CVRF profiles were significantly related to specific WMH spatial distribution patterns in a large IS cohort. KEY POINTS: • An observational study of WMH in a large IS cohort was assessed by a modified visual evaluation. • Different CVRF profiles were significantly related to specific WMH spatial distribution patterns. • Distinct WMH anatomical patterns could be related to different pathophysiological mechanisms.

Leukoaraiosis severity and post-reperfusion outcomes in acute ischaemic stroke: A meta-analysis.

OBJECTIVES: Severity of leukoaraiosis may mediate outcomes after reperfusion therapy in acute ischaemic stroke (AIS) patients. However, the level of the association remains poorly understood. We performed a meta-analysis to investigate the impact of leukoaraiosis severity on functional outcome, survival, haemorrhagic complications, and procedural success in AIS patients treated with intravenous thrombolysis and/or endovascular thrombectomy. MATERIALS AND METHODS: PubMed, EMBASE and the Cochrane library were searched for studies on leukoaraiosis in AIS receiving reperfusion therapy. A random-effects meta-analysis was conducted for post-reperfusion outcomes in AIS patients with absent-to-mild leukoaraiosis and moderate-to-severe leukoaraiosis. The strength of association between moderate-to-severe leukoaraiosis and poor outcomes was quantified using odds ratios (OR). RESULTS: A total of 15 eligible studies involving 6460 patients (1451 with moderate-to-severe leukoaraiosis and 5009 with absent-to-mild leukoaraiosis) were included in the meta-analysis. Moderate-to-severe leukoaraiosis was significantly associated with poor 90-day functional outcome (OR 3.16; 95% confidence interval (CI) 2.69-3.72; p < .0001), 90-day mortality (OR 3.11; 95% CI 2.27-4.26; p < .0001) and increased risk of symptomatic intracerebral haemorrhage (OR 1.69; 95% CI 1.24-2.32; p = .001) after reperfusion therapy. Overall, no significant association of leukoaraiosis severity with haemorrhagic transformation (HT) and angiographic recanalization status were observed. However, subgroup analysis revealed a significant association of WML severity with HT in patients receiving EVT. CONCLUSION: Leukoaraiosis is a useful prognostic biomarker in AIS. Patients with moderate-to-severe leukoaraiosis on baseline imaging are likely to have worse clinical and safety outcomes after reperfusion therapy.

A novel protein truncating mutation in L2HGDH causes L-2-hydroxyglutaric aciduria in a consanguineous Pakistani family.

BACKGROUND: L-2-hydroxyglutaric aciduria (L2HGA) is a rare neurometabolic disorder that occurs due to accumulation of L-2-hydroxyglutaric acid in the cerebrospinal fluid (CSF), plasma and urine. The clinical manifestation of L2HGA includes intellectual disability, cerebellar ataxia, epilepsy, speech problems and macrocephaly. METHODS: In the present study, we ascertained a multigenerational consanguineous Pakistani family with 5 affected individuals. Clinical studies were performed through biochemical tests and brain CT scan. Locus mapping was carried out through genome-wide SNP genotyping, whole exome sequencing and Sanger sequencing. For in silico studies protein structural modeling and docking was done using I-TASSER, Cluspro and AutoDock VINA tools. RESULTS: Affected individuals presented with cognitive impairment, gait disturbance, speech difficulties and psychomotor delay. Radiologic analysis of a male patient revealed leukoaraiosis with hypoattenuation of cerebral white matter, suggestive of hypomyelination. Homozygosity mapping in this family revealed a linkage region on chromosome 14 between markers rs2039791 and rs781354. Subsequent whole exome analysis identified a novel frameshift mutation NM_024884.3:c.180delG, p.(Ala62Profs*24) in the second exon of L2HGDH. Sanger sequencing confirmed segregation of this mutation with the disease phenotype. The identification of the most N-terminal loss of function mutation published thus far further expands the mutational spectrum of L2HGDH.

A pilot study of the association between leukoaraiosis and cerebral atherosclerosis using synthetic magnetic resonance imaging.

BACKGROUND: Leukoaraiosis is a type of lesion characterized by tissue rarefaction or myelin pallor resulting from axons loss and gliosis. Synthetic magnetic resonance imaging (MRI) could yield quantitative T1, T2, proton density (PD) values of leukoaraiosis in addition to information on the volume of the lesion. PURPOSE: To investigate the feasibility of quantifying leukoaraiosis using synthetic MRI and to explore the association between leukoaraiosis and cerebral small vascular diseases and cerebral atherosclerosis. MATERIAL AND METHODS: Patients with acute ischemic stroke were enrolled in this study. All participants underwent a conventional T2-weighted image, brain volume, CUBE fluid attenuated inversion recovery, and synthetic MRI acquisition using a 3.0-T MR system. A time-of-flight magnetic resonance angiography was also obtained. We evaluated the T1, T2, PD values and leukoaraiosis volume. RESULTS: Analysis of the leukoaraiosis volume ratios demonstrated a positive association with T2 values, a negative association with T1 values, and no association with PD values. Leukoaraiosis volume ratios were independently correlated with age (P < 0.001), lacunes (P = 0.022), and cerebral microbleeds (P = 0.010). A statistical association was found between both age (P < 0.001) and lacunes (P = 0.047) and leukoaraiosis T2 values. CONCLUSION: Synthetic MRI may enhance the evaluation of leukoaraiosis, in addition to providing information on its volume. Leukoaraiosis may represent a type of cerebral small vascular disease rather than cerebral atherosclerosis and may share the same pathological mechanism as lacunes and cerebral microbleeds.

The association between white matter hyperintensity volume and cognitive/physical decline in older people with dementia: A one-year longitudinal study.

OBJECTIVES: Understanding the relationship between white matter hyperintensities (WMHs) and cognitive and physical decline in people with dementia will assist in determining potential treatment strategies. Currently there is conflicting evidence describing the association between WMHs and cognitive decline and, WMHs association with declines in objective measures of physical function have not been examined. We examined the relationship between baseline WMH volume and physical/cognitive decline over one-year in older people with dementia. METHODS: Twenty-six community-dwelling older people with dementia (mean age = 81 ± 8 years; 35% female) were assessed at baseline and follow-up (one-year) using the Addenbrooke's Cognitive Examination-Revised (including verbal fluency), Trail Making Test A, the Physiological Profile Assessment (PPA), timed-up-and-go (TUG) and gait speed. WMH volumes were quantified using a fully automated segmentation toolbox, UBO Detector. RESULTS: In analyses adjusted for baseline performance, higher baseline WMH volume was associated with decline in executive function (verbal fluency), sensorimotor function (PPA) and mobility (TUG). Executive function (semantic/category fluency) was the only domain association that withstood adjustment for age, and additionally hippocampal volume. CONCLUSIONS: In unadjusted analyses, WMH volume was associated with one-year declines in cognitive and physical function in older people with dementia. The association with executive function decline withstood adjustment for age. More research is needed to confirm these findings and explore whether vascular risk reduction strategies can reduce WMH volume and associated cognitive and physical impairments in this group.