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Epilepsy is a common and serious neurological disorder, with many different constituent conditions characterized by their electro clinical, imaging, and genetic features. MRI has been fundamental in advancing our understanding of brain processes in the epilepsies. Smaller-scale studies have identified many interesting imaging phenomena, with implications both for understanding pathophysiology and improving clinical care. Through the infrastructure and concepts now well-established by the ENIGMA Consortium, ENIGMA-Epilepsy was established to strengthen epilepsy neuroscience by greatly increasing sample sizes, leveraging ideas and methods established in other ENIGMA projects, and generating a body of collaborating scientists and clinicians to drive forward robust research. Here we review published, current, and future projects, that include structural MRI, diffusion tensor imaging (DTI), and resting state functional MRI (rsfMRI), and that employ advanced methods including structural covariance, and event-based modeling analysis. We explore age of onset- and duration-related features, as well as phenomena-specific work focusing on particular epilepsy syndromes or phenotypes, multimodal analyses focused on understanding the biology of disease progression, and deep learning approaches. We encourage groups who may be interested in participating to make contact to further grow and develop ENIGMA-Epilepsy.

The epilepsies are commonly accompanied by widespread abnormalities in cerebral white matter. ENIGMA-Epilepsy is a large quantitative brain imaging consortium, aggregating data to investigate patterns of neuroimaging abnormalities in common epilepsy syndromes, including temporal lobe epilepsy, extratemporal epilepsy, and genetic generalized epilepsy. Our goal was to rank the most robust white matter microstructural differences across and within syndromes in a multicentre sample of adult epilepsy patients. Diffusion-weighted MRI data were analysed from 1069 healthy controls and 1249 patients: temporal lobe epilepsy with hippocampal sclerosis (n = 599), temporal lobe epilepsy with normal MRI (n = 275), genetic generalized epilepsy (n = 182) and non-lesional extratemporal epilepsy (n = 193). A harmonized protocol using tract-based spatial statistics was used to derive skeletonized maps of fractional anisotropy and mean diffusivity for each participant, and fibre tracts were segmented using a diffusion MRI atlas. Data were harmonized to correct for scanner-specific variations in diffusion measures using a batch-effect correction tool (ComBat). Analyses of covariance, adjusting for age and sex, examined differences between each epilepsy syndrome and controls for each white matter tract (Bonferroni corrected at P

The behavioural variant of frontotemporal dementia (bvFTD) is a frequent cause of early-onset dementia. The diagnosis of bvFTD remains challenging because of the limited accuracy of neuroimaging in the early disease stages and the absence of molecular biomarkers, and therefore relies predominantly on clinical assessment. BvFTD shows significant symptomatic overlap with non-degenerative primary psychiatric disorders including major depressive disorder, bipolar disorder, schizophrenia, obsessive-compulsive disorder, autism spectrum disorders and even personality disorders. To date, ∼50% of patients with bvFTD receive a prior psychiatric diagnosis, and average diagnostic delay is up to 5-6 years from symptom onset. It is also not uncommon for patients with primary psychiatric disorders to be wrongly diagnosed with bvFTD. The Neuropsychiatric International Consortium for Frontotemporal Dementia was recently established to determine the current best clinical practice and set up an international collaboration to share a common dataset for future research. The goal of the present paper was to review the existing literature on the diagnosis of bvFTD and its differential diagnosis with primary psychiatric disorders to provide consensus recommendations on the clinical assessment. A systematic literature search with a narrative review was performed to determine all bvFTD-related diagnostic evidence for the following topics: bvFTD history taking, psychiatric assessment, clinical scales, physical and neurological examination, bedside cognitive tests, neuropsychological assessment, social cognition, structural neuroimaging, functional neuroimaging, CSF and genetic testing. For each topic, responsible team members proposed a set of minimal requirements, optimal clinical recommendations, and tools requiring further research or those that should be developed. Recommendations were listed if they reached a ≥ 85% expert consensus based on an online survey among all consortium participants. New recommendations include performing at least one formal social cognition test in the standard neuropsychological battery for bvFTD. We emphasize the importance of 3D-T1 brain MRI with a standardized review protocol including validated visual atrophy rating scales, and to consider volumetric analyses if available. We clarify the role of 18F-fluorodeoxyglucose PET for the exclusion of bvFTD when normal, whereas non-specific regional metabolism abnormalities should not be over-interpreted in the case of a psychiatric differential diagnosis. We highlight the potential role of serum or CSF neurofilament light chain to differentiate bvFTD from primary psychiatric disorders. Finally, based on the increasing literature and clinical experience, the consortium determined that screening for C9orf72 mutation should be performed in all possible/probable bvFTD cases or suspected cases with strong psychiatric features.

Objectives: Mental health triage services are the first contact for people wanting support for their mental health and provide access to public mental health services in Victoria, Australia. People living with young-onset dementia and their families may contact triage services seeking assistance for behaviour changes and pathways to care as there are few alternative services available. Methods: The authors reviewed the minimum triage dataset from one of the largest mental health services in Victoria, Australia from 2018 to 2021 investigating reasons for referral for people with young-onset dementia. Results: Of the 1766 referrals for 'dementia', 145 were for young-onset dementia. Of these, 69% were referred for behaviour changes. About half of the referrals for behaviour changes were triaged as 'advice only'. One-third of referrals were from general practitioners. Conclusions: The availability of dementia-specific support services that could provide advice on dementia as well as advice for behaviour changes related to the disease could potentially ease the burden of phone calls received by mental health triage services. What is known about the topic? Young-onset dementia refers to a dementia with onset at less than 65 years of age. People with young-onset dementia may contact mental health services for support but the reasons for contact are unknown. What does this paper add? The reasons for contacting one Victorian mental health service included behaviour changes such as agitation or aggression and psychotic symptoms (74%) and general advice, including about dementia pathways (14%). General practitioners made up one-third of referral sources. What are the implications for practitioners? Victorian mental health services are generally overloaded and complex. There is a need to promote alternative dementia support organisations in order to provide an alternative contact for people affected by young-onset dementia. [ABSTRACT FROM AUTHOR]

Objective Given the rapid shift to in-home teleneuropsychology models, more research is needed to investigate the equivalence of non-facilitator models of teleneuropsychology delivery for people with younger onset dementia (YOD). This study aimed to determine whether equivalent performances were observed on neuropsychological measures administered in-person and via teleneuropsychology in a sample of people being investigated for YOD. Method Using a randomized counterbalanced cross-over design, 43 participants (M age = 60.26, SD age = 7.19) with a possible or probable YOD diagnosis completed 14 neuropsychological tests in-person and via teleneuropsychology, with a 2-week interval. Repeated measures t -tests, intraclass correlation coefficients (ICC), and Bland Altman analyses were used to investigate equivalence across the administration conditions. Results No statistical differences were found between in-person and teleneuropsychology conditions, except for the Hospital Anxiety and Depression Scale Anxiety subtest. Small to negligible effect sizes were observed (ranging from.01 to.20). ICC estimates ranged from.71 to.97 across the neuropsychological measures. Bland Altman analyses revealed that the Wechsler Adult Intelligence Scale—Fourth Edition Block Design subtest had slightly better overall performance in the in-person condition and participants reported higher levels of anxiety symptoms during the teleneuropsychology condition; however, average anxiety symptoms remained within the clinically normal range. Participants reported a high level of acceptability for teleneuropsychology assessments. Conclusions These results suggest that performances are comparable between in-person and teleneuropsychology assessment modalities. Our findings support teleneuropsychology as a feasible alternative to in-person neuropsychological services for people under investigation of YOD, who face significant barriers in accessing timely diagnoses and treatment options. [ABSTRACT FROM AUTHOR]

Objectives: Individuals living with young-onset dementia fall through the gaps of adult and geriatric services. Given that non-cognitive symptoms of dementia in younger people are often psychiatric and behavioural in nature, these people may contact mental health services. There is sparse information investigating the frequency of people with young-onset dementia who contact mental health triage in Victoria. Methods: Triage data were obtained from the Victorian Agency for Health Information. The data contained demographics for people registered with Victorian mental health services. Consumers who had an International Classification for Diseases code for dementia and were aged less than 65 years were identified as people with young-onset dementia. Using information of the frequency of people with young-onset dementia who were registered with each area-based mental health service, population census statistics were used to make estimates of the frequency of young-onset dementia. Results: Of the 6172 people who had a dementia diagnosis, 1020 of them were aged less than 65 years and had young-onset dementia. There were proportionally more men who had young-onset dementia compared to women. There were more people with young-onset dementia registered to rural mental health services compared to metropolitan services. Conclusion: Findings provide important information for service planning in Victoria. Recommendations include upskilling and education for the assessment of dementia for those clinicians who work in mental health services, particularly in rural regions. What is known about the topic? Young-onset dementia refers to a dementia with onset at an age less than 65 years. Accessing age-appropriate services for these people is difficult as they fall through the gaps of adult and aged services due to their age. What does this paper add? Due to the behavioural and psychiatric manifestations related to young-onset dementia, data is provided about mental health service involvement for these people. What are the implications for practitioners? There is a need to upskill mental health clinicians, especially in rural areas, as younger people with dementia are accessing these services. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is characterized by two primary pathologies: tau-related neurofibrillary tangles and the extracellular accumulation of amyloid-β (Aβ). The development of these pathologies is topologically distinct early in the disease, with Aβ beginning to accumulate as a diffuse, neocortical pathology, while tau-related pathology begins to form in mesial temporal regions. This study investigated the hypothesis that, by virtue of this distinction, there exist preferential associations between the primary pathologies and aspects of the cognitive phenotype. We investigated the relationship between cerebrospinal fluid (CSF) biomarkers for tau and Aβ pathologies with neurocognitive measures in 191 patients with mild cognitive impairment (MCI). Participants completed cognitive tests of new learning, information processing speed, and working memory. Separate regression models were computed and then followed up with mediation analyses to examine the predictive status of CSF biomarkers. The effect of Aβ on learning was mediated by phospho-tau (p = 0.008). In contrast, Aβ had a direct effect on information processing speed that was not mediated by phospho-tau (p = 0.59). No predictors were significant for working memory. This study provided evidence for a differential relationship of Aβ and phospho-tau pathologies on the neurocognitive phenotype of MCI. This supports the proposition that these primary AD pathologies maximally affect different aspects of cognition, and has potential implications for cognitive assessments and the use of biomarkers in disease-modifyingtherapeutic trials.

ObjectiveTo investigate partial volume correction (PVC) of 2-[F]-fluoro-2-deoxy-D-glucose positron emission tomography in Alzheimer disease in a longitudinal context.MethodsA total of 115 participants were included, including 55 controls, 53 patients with mild cognitive impairment, and 7 patients with dementia of the Alzheimer type. Imaging was performed at baseline and 24 months. Partial volume corrected vs uncorrected rates of longitudinal change were compared for mesial temporal and cortical regions of interest.ResultsPartial volume correction increased apparent uptake, and this effect was greater at 24 months compared with baseline. Partial volume correction decreased the rate of decline, causing an apparent increase in uptake at 24 months compared with baseline. This effect was correlated with the structural atrophy.ConclusionsThese findings suggest that applying PVC in a longitudinal context in Alzheimer disease might produce unpredictable results. Accordingly, both PVC corrected and uncorrected data should be reported to ensure that the results are physiologically plausible.