A Randomized Control Trial of a Virtually Delivered Program for Increasing Upper Limb Activity After Stroke.

Background: Upper limb activity following stroke is low, which may limit recovery. We investigated whether a virtually-delivered upper limb program, that included a wearable device with reach-to-grasp feedback, would increase upper limb activity after stroke.

Methods: This was a parallel-group, assessor-blinded, randomized control trial conducted at 6 sites across 5 provinces of the CanStroke Recovery Trials Platform between 2020 to 2022.

segcsvd: A Convolutional Neural Network-Based Tool for Quantifying White Matter Hyperintensities in Heterogeneous Patient Cohorts.

White matter hyperintensities (WMH) of presumed vascular origin are a magnetic resonance imaging (MRI)-based biomarker of cerebral small vessel disease (CSVD). WMH are associated with cognitive decline and increased risk of stroke and dementia, and are commonly observed in aging, vascular cognitive impairment, and neurodegenerative diseases. The reliable and rapid measurement of WMH in large-scale multisite clinical studies with heterogeneous patient populations remains challenging, where the diversity of imaging characteristics across studies adds additional complexity to this task.

Homocysteine, neurodegenerative biomarkers, and APOE ε4 in neurodegenerative diseases.

Introduction: Elevated plasma homocysteine (Hcy) is associated with an increased risk of developing neurodegenerative diseases; however, its relationship with the apolipoprotein E (APOE) ε4 allele has not been well characterized.

Methods: Participants clinically diagnosed with Alzheimer's disease or mild cognitive impairment (AD/MCI), frontotemporal dementia, Parkinson's disease, or cerebrovascular disease were stratified by the presence of the APOE ε4 allele. Volumetric magnetic resonance imaging, plasma amyloid/tau/neurodegeneration biomarkers, and cognitive performance were quantified.

White matter microstructure in obesity and bipolar disorders: an ENIGMA bipolar disorder working group study in 2186 individuals.

Although specific risk factors for brain alterations in bipolar disorders (BD) are currently unknown, obesity impacts the brain and is highly prevalent in BD. Gray matter correlates of obesity in BD have been well documented, but we know much less about brain white matter abnormalities in people who have both obesity and BD. We obtained body mass index (BMI) and diffusion tensor imaging derived fractional anisotropy (FA) from 22 white matter tracts in 899 individuals with BD, and 1287 control individuals from 20 cohorts in the ENIGMA-BD working group.

Retinal microvascular phenotypes can track small vessel disease burden and CPAP treatment effectiveness in obstructive sleep apnoea.

Optical coherence tomography angiography (OCT-A) retinal imaging enables visualization of the retinal microvasculature that is developmentally related to the brain and can offer insight on cerebrovascular health. We investigated retinal phenotypes and neuroimaging markers of small vessel disease (SVD) in individuals with obstructive sleep apnoea (OSA). We enrolled 44 participants (mean age 50.

Are white matter hyperintensities associated with neuroborreliosis? The answer is twofold.

Purpose: Many consider white matter hyperintensities (WMHs) to be important imaging findings in neuroborreliosis. However, evidence regarding association with WMHs is of low quality. The objective was to investigate WMHs in neuroborreliosis visually and quantitatively.

Twinned neuroimaging analysis contributes to improving the classification of young people with autism spectrum disorder.

Autism spectrum disorder (ASD) is diagnosed using comprehensive behavioral information. Neuroimaging offers additional information but lacks clinical utility for diagnosis. This study investigates whether multi-forms of magnetic resonance imaging (MRI) contrast can be used individually and in combination to produce a categorical classification of young individuals with ASD.

Effects of post-acute COVID-19 syndrome on cerebral white matter and emotional health among non-hospitalized individuals.

Introduction: Post-acute COVID syndrome (PACS) is a growing concern, given its impact on mental health and quality of life. However, its effects on cerebral white matter remain poorly understood, particularly in non-hospitalized cohorts. The goals of this cross-sectional, observational study were to examine (1) whether PACS was associated with distinct alterations in white matter microstructure, compared to symptom-matched non-COVID viral infection; and (2) whether microstructural alterations correlated with indices of post-COVID emotional health.

Gadolinium-Enhanced T2 FLAIR Is an Imaging Biomarker of Radiation Necrosis and Tumor Progression in Patients with Brain Metastases.

Background And Purpose: Differentiating radiation necrosis (RN) from tumor progression (TP) after radiation therapy for brain metastases is an important clinical problem requiring advanced imaging techniques that may not be widely available and are challenging to perform at multiple time points. The ability to leverage conventional MRI for this problem could have a meaningful clinical impact. The purpose of this study was to explore contrast-enhanced T2 FLAIR (T2FLAIRc) as a new imaging biomarker of RN and TP.

Cytochrome P450-soluble epoxide hydrolase oxylipins, depression and cognition in type 2 diabetes.

Aims: This study examined serum cytochrome P450-soluble epoxide hydrolase (CYP450-sEH) oxylipins and depressive symptoms together in relation to cognitive performance in individuals with type 2 diabetes mellitus (T2DM).

Methods: Clinically cognitively normal T2DM individuals were recruited (NCT04455867). Depressive symptom severity was assessed using the Beck Depression Inventory-II (BDI-II; total scores ≤13 indicated minimal depressive symptoms and ≥ 14 indicated significant depressive symptoms).

Cerebral blood flow in relation to peripheral endothelial function in youth bipolar disorder.

Introduction: Anomalous cerebral blood flow (CBF) is evident in bipolar disorder (BD), however the extent to which CBF reflects peripheral vascular function in BD is unknown. This study investigated endothelial function, an index of early atherosclerosis and cardiovascular disease risk, in relation to CBF among youth with BD.

Methods: Participants included 113 youth, 13-20 years old (66 BD; 47 healthy controls [HC]).

Pilot study of circulating cell-free mitochondrial DNA in relation to brain structure in youth bipolar disorder.

Background: Mitochondrial dysfunction is implicated in the neuropathology of bipolar disorder (BD). Higher circulating cell-free mitochondrial DNA (ccf-mtDNA), generally reflecting poorer mitochondrial health, has been associated with greater symptoms severity in BD. The current study examines the association of serum ccf-mtDNA and brain structure in relation to youth BD.

Standardized evaluation of the extent of resection in glioblastoma with automated early post-operative segmentation.

Standard treatment of patients with glioblastoma includes surgical resection of the tumor. The extent of resection (EOR) achieved during surgery significantly impacts prognosis and is used to stratify patients in clinical trials. In this study, we developed a U-Net-based deep-learning model to segment contrast-enhancing tumor on post-operative MRI exams taken within 72 h of resection surgery and used these segmentations to classify the EOR as either maximal or submaximal.

Persistent fatigue in post-acute COVID syndrome is associated with altered T1 MRI texture in subcortical structures: a preliminary investigation.

Post-acute COVID syndrome (PACS) is a global health concern and is often associated with debilitating symptoms. Post-COVID fatigue is a particularly frequent and troubling issue, and its underlying mechanisms remain incompletely understood. One potential contributor is micropathological injury of subcortical and brainstem structures, as has been identified in other patient populations.

Recommendations for quantitative cerebral perfusion MRI using multi-timepoint arterial spin labeling: Acquisition, quantification, and clinical applications.

Accurate assessment of cerebral perfusion is vital for understanding the hemodynamic processes involved in various neurological disorders and guiding clinical decision-making. This guidelines article provides a comprehensive overview of quantitative perfusion imaging of the brain using multi-timepoint arterial spin labeling (ASL), along with recommendations for its acquisition and quantification. A major benefit of acquiring ASL data with multiple label durations and/or post-labeling delays (PLDs) is being able to account for the effect of variable arterial transit time (ATT) on quantitative perfusion values and additionally visualize the spatial pattern of ATT itself, providing valuable clinical insights.

Investigating the impact of hypertension with and without diabetes on Alzheimer's disease risk: A clinico-pathological study.

Introduction: Hypertension and diabetes are common cardiovascular risk factors that increase Alzheimer's disease (AD) risk. However, it is unclear whether AD risk differs in hypertensive individuals with and without diabetes.

Methods: Cognitively normal individuals (N = 11,074) from the National Alzheimer's Coordinating Center (NACC) were categorized as having (1) hypertension with diabetes (HTN+/DM+), (2) hypertension without diabetes (HTN+/DM-), or (3) neither (HTN-/DM-).

An empirical analysis of structural neuroimaging profiles in a staging model of depression.

We examine structural brain characteristics across three diagnostic categories: at risk for serious mental illness; first-presenting episode and recurrent major depressive disorder (MDD). We investigate whether the three diagnostic groups display a stepwise pattern of brain changes in the cortico-limbic regions. Integrated clinical and neuroimaging data from three large Canadian studies were pooled (total n = 622 participants, aged 12-66 years).