Cortical Atrophy Research Articles

Autosomal Recessive Spastic Paraplegia Type 51 Caused by Homozygous Mutation of the AP4E1 Gene: A Case Report of a 17-Years-Old Boy

Autosomal recessive spastic paraplegia-51 (SPG51) is a rare neurodevelopmental disorder caused by a homozygous mutation in the AP4E1 gene, located on chromosome 15q21. Spastic paraplegia-51 (SPG51) is an extremely rare autosomal recessive neurodevelopmental disorder characterized by neonatal hypotonia that progresses to hypertonia and spasticity. Mutations in the AP-4E1 gene on chromosome 15q21.2, which is part of the AP-4 complex, can lead to autosomal recessive spastic paraplegia 51 (SPG51). Different mutations in this gene have been identified in affected individuals, leading to disruption of the AP4 complex and vesicular trafficking processes. The specific characteristics of SPG51 are, due to only few cases, not well understood due to limited reports of affected families. Affected individuals also have global developmental delay with impaired intellectual development and poor or absent speech. Studies linked to an additive symptom of persistent stuttering. Affected individuals typically present with hypotonia in the neonatal period, which progresses to muscular hypertonia, especially in the lower limbs. They may also exhibit contractures, talipes equinovarus, decreased muscle mass, short stature, and microcephaly. Severe mental retardation, absent speech, and dysmorphic facial features are common. Some patients may experience seizures. Neurological examination often reveals spastic paraplegia of the lower limbs, and brain imaging may show atrophy of the cerebellar vermis and cortical atrophy. We present an extremely rare case of a 17 years-old boy with autosomal recessive spastic paraplegia type 51.

Atlas-based structural analysis of prefrontal cortex atrophy in major depressive disorder: Correlations with severity and episode frequency

BackgroundCurrent models of major depressive disorder (MDD) primarily focus on the structural and functional changes in key prefrontal areas responsible for emotional regulation. Among these regions some sections such as the dorsal prefrontal area, has received limited attention regarding its structural abnormalities in MDD. This study aims to evaluate volumetric abnormalities in brain regions associated with markers of depression severity and episode frequency. MethodsThe study included 33 MDD patients and 33 healthy subjects. Using an atlas-based method, we measured the volumes of several key brain regions based on MRI data. The regions of interest included prefrontal and posterior sections of the middle frontal gyrus (MFG) and superior frontal gyrus (SFG). Additionally, we evaluated the volumes of the dorsal anterior cingulate cortex (dACC), perigenual (rostral) anterior cingulate cortex (pgACC), subgenual cingulate cortex (sgACC), posterior cingulate cortex (PCC), hippocampus (HPC), and parahippocampus (paraHPC). Hamilton Depression Scale (HAM-D) scores and count of the depressive episodes of patients were also obtained. A regression analysis with sex as the confounding factor has been made. ResultsAnalysis of covariances, controlling for sex, showed significant atrophy in the sgACC in the depression group: F(1, 63) = 4.013, p = 0.049 (left) and F(1, 63) = 8.786, p < 0.004 (right). Poisson regression, also controlling for sex, found that each additional depressive episode was associated with a significant reduction in left posterior MFG volume (0.952 times, 95 % CI, 0.906 to 1.000; p = 0.049). ConclusionsFindings in this study highlight the structural abnormalities in MDD patients in correlation to either current depression severity or chronicity of the disease.

Predicting brain atrophy and cognitive aging trajectories with baseline subjective cognitive concerns in cognitively normal older adults

Subjective cognitive concerns (SCC) are common even in cognitively normal older adults who lack objectively-detectable deficits on standard neuropsychological evaluation. The clinical relevance of these concerns, particularly considering the nature of concerns (e.g., memory versus non-memory), remains unclear. Thus, we examined whether baseline memory and non-memory SCC relate to longitudinal change in brain volume and neuropsychological test performance in 476 functionally-intact, objectively unimpaired older adults (Mage = 72y, 56 % female, follow-up time = 1 – 9 years). Mixed-effects models revealed that both higher baseline memory and non-memory SCC predicted greater atrophy in total gray matter and dorsolateral prefrontal cortex atrophy over time, while only memory SCC predicted steeper medial temporal lobe atrophy. Regarding neuropsychological performance, higher non-memory SCC predicted decline in processing speed performance, while memory SCC did not predict neuropsychological trajectories. SCC are a risk factor for more adverse brain and cognitive aging trajectories, even in functionally-intact, seemingly cognitively normal older adults.

Factors associated with cognitive impairment before intracerebral haemorrhage: community-based neuropathological study.

Little is known about whether clinical, radiological or neuropathological features are associated with cognitive impairment before intracerebral haemorrhage. We conducted a community-based cohort study of 125 adults with intracerebral haemorrhage (lobar n = 71, non-lobar n = 54) with consent to brain autopsy. We compared small vessel disease biomarkers on diagnostic CT head and neuropathological findings including neurofibrillary tangles and amyloid plaques in adults without cognitive impairment versus cognitive impairment without dementia versus dementia before intracerebral haemorrhage, stratified by lobar and non-lobar intracerebral haemorrhage. In non-lobar intracerebral haemorrhage, severe cortical atrophy was less common in those without cognitive impairment (8/36, 22%) and cognitive impairment without dementia (0/9, 0%) versus dementia (5/9, 56%); P = 0.008. Irrespective of intracerebral haemorrhage location, adults without cognitive impairment had milder neurofibrillary tangle pathology measured by median Braak stage (lobar intracerebral haemorrhage: no cognitive impairment 2 [interquartile range, 2-3] versus cognitive impairment without dementia 4 [2-6] versus dementia 5.5 [4-6]; P = 0.004; non-lobar intracerebral haemorrhage: no cognitive impairment 2 [1-2] versus cognitive impairment without dementia 2 [1-2] versus dementia 5 [3-6]; P < 0.001). Irrespective of intracerebral haemorrhage location, adults without cognitive impairment had milder amyloid plaque pathology measured by median Thal stage (lobar intracerebral haemorrhage: no cognitive impairment 2 [1-2] versus cognitive impairment without dementia 2 [2-3] versus dementia 2.5 [2-3.5]; P = 0.033; non-lobar intracerebral haemorrhage: no cognitive impairment 1 [0-1] versus cognitive impairment without dementia 0 [0-2] versus dementia 3 [2-3]; P = 0.002). Our findings suggest that irrespective of intracerebral haemorrhage location, adults with cognitive impairment before an intracerebral haemorrhage have more Alzheimer's disease neuropathologic change.

Association of outer retinal and choroidal alterations with neuroimaging and clinical features in posterior cortical atrophy

BackgroundPosterior cortical atrophy (PCA) is a rare condition characterized by early-onset and progressive visual impairment. Individuals with PCA have relatively early-onset and progressive dementia, posing certain needs for early detection. Hence, this study aimed to investigate the association of alterations in outer retinal and choroidal structure and microvasculature with PCA neuroimaging and clinical features and the possible effects of apolipoprotein E(APOE) ε4 allele on outer retinal and choroidal alterations in participants with PCA, to detect potential ocular biomarkers for PCA screening.MethodsThis cross-sectional study included PCA and age- and sex-matched healthy control participants from June 2022 to December 2023. All participants with PCA completed a comprehensive neurological evaluation. All participants were recorded baseline information and underwent an ophthalmic evaluation. Quantitative analyses were performed using swept-source optical coherence tomography (SS-OCT) and angiography (SS-OCTA). Adaptive optics scanning laser ophthalmoscopy (AO-SLO) was performed in some patients. In participants with PCA, the influence of APOE ε4 on outer retinal and choroidal alterations and the correlation of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA were investigated.ResultsA total of 28 participants (53 eyes) with PCA and 56 healthy control participants (112 eyes) were included in the current study. Compared with healthy control participants, participants with PCA had significantly reduced outer retinal thickness (ORT) (p < 0.001), choriocapillaris vessel density (VD) (p = 0.007), choroidal vascular index (CVI) (p = 0.005) and choroidal vascular volume (CVV) (p = 0.003). In participants with PCA, APOE ε4 carriers showed thinner ORT (p = 0.009), and increased choriocapillaris VD (p = 0.004) and CVI (p = 0.004). The PCA neuroimaging features were positively associated with the ORT, CVI and CVV. Furthermore, differential correlations were observed of PCA clinical features with the CRT, CVV and CVI.ConclusionsOur findings highlighted the association of outer retinal and choroidal alterations with PCA neuroimaging and clinical features in participants with PCA. Noninvasive SS-OCT and SS-OCTA can provide potential biomarkers for the diagnosis and management of PCA, improving awareness of PCA syndrome among ophthalmologists, neurologists, and primary care providers.

Brain MRI in patients with V30M hereditary transthyretin amyloidosis

Background Central nervous system dysfunction is common in longstanding hereditary transthyretin amyloidosis (ATTRv) caused by the V30M (p.V50M) mutation. Neuropathology studies show leptomeningeal amyloid deposition and cerebral amyloid angiopathy (CAA). Brain MRI is widely used in the assessment of Aβ associated CAA but there are no systematic studies with brain MRI in ATTRv amyloidosis. Methods we performed 3 T brain MRIs in 16 patients with longstanding (>14 years) ATTRV30M. We additionally retrospectively reviewed 48 brain MRIs from patients followed at our clinic. CNS symptoms and signs were systematically accessed, and MRIs were blindly reviewed for ischaemic and haemorrhagic lesions. Results in the prospective cohort, we found white matter hyperintensities in 8/16 patients (50%, Fazekas score> =1). There were no relevant microbleeds, large ischaemic or haemorrhagic lesions or superficial siderosis. In the retrospective cohort, microbleeds were found in 5/48 patients (10,4%), two of which with > =20 microbleeds. White matter hyperintensities were found in 20/48 cases (41.7%). White matter lesions, microbleeds and cortical atrophy were not associated with disease duration. Conclusions white matter hyperintensities are common in ATTRV30M, irrespective of disease duration. Haemorrhagic lesions are rare, even in patients with longstanding disease, suggesting the existence of other risk factors.

Spatial and temporal patterns of cortical mean diffusivity in Alzheimer's disease and suspected non-Alzheimer's disease pathophysiology.

The spatial and temporal patterns of cortical mean diffusivity (cMD), as well as its association with Alzheimer's disease (AD) and suspected non-Alzheimer's pathophysiology (SNAP), are not yet fully understood. We compared baseline (n=617) and longitudinal changes (n=421) of cMD, cortical thickness, and gray matter volume and their relations to vascular risk factors, amyloid beta (Aβ), and tau positron emission tomography (PET), and longitudinal cognitive decline in Aβ PET negative and positive older adults. cMD increases were more sensitive to detecting brain structural alterations than cortical thinning and gray matter atrophy. Tau-related cMD increases partially mediated Aβ-related cognitive decline in AD, whereas vascular disease-related increased cMD levels substantially mediated age-related cognitive decline in SNAP. These findings revealed the dynamic changes of microstructural and macrostructural indicators and their associations with AD and SNAP, providing novel insights into understanding upstream and downstream events of cMD in neurodegenerative disease. Cortical mean diffusivity (cMD) was more sensitive to detecting structural changes than macrostructural factors. Tau-related cMD increases partially mediated amyloid beta-related cognitive decline in Alzheimer's disease (AD). White matter hyperintensity-related higher cMD mainly explained the age-related cognitive decline in suspected non-Alzheimer's pathophysiology (SNAP). cMD may assist in tracking earlier neurodegenerative signs in AD and SNAP.

Distinct Patterns of Brain Atrophy in Amnestic Mild Cognitive Impairment and Motoric Cognitive Risk Syndromes.

Motoric cognitive risk (MCR) and amnestic mild cognitive impairment (aMCI) syndromes are each reliable predictors of incident Alzheimer's disease (AD), but MCR may be a stronger predictor of vascular dementia than AD. This study contrasted cortical and hippocampal atrophy patterns in MCR and aMCI. Cross-sectional data from 733 older adults without dementia or disability (M age = 73.6; 45% women) in the multicountry MCR consortium were examined. MCR was defined as presence of slow gait and cognitive concerns. Amnestic MCI was defined as poor episodic memory performance and cognitive concerns. Cortical thickness and hippocampal volumes were quantified from structural MRIs. Multivariate and univariate general linear models were used to examine associations between cortical thickness and hippocampal volume in MCR and aMCI, adjusting for age, sex, education, total intracranial volume, white matter lesions, and study site. The prevalence of MCR and aMCI was 7.64% and 12.96%, respectively. MCR was associated with widespread cortical atrophy, including prefrontal, insular, cingulate, motor, parietal, and temporal atrophy. aMCI was associated with hippocampal atrophy. Distinct patterns of atrophy were associated with MCR and aMCI. A distributed pattern of cortical atrophy - that is more consistent with VaD or mixed dementia- was observed in MCR. A more restricted pattern of atrophy - that is more consistent with AD - was observed in aMCI. The biological underpinnings of MCR and aMCI likely differ and may require tailored interventions.

Cortical atrophy patterns in myelin oligodendrocyte glycoprotein antibody-associated disease.

Global brain volume changes in patients with myelin oligodendrocyte glycoprotein antibody-associated disease compared with healthy controls (HC) could be revealed by magnetic resonance imaging, but specific atrophy patterns of cortical structures and relation to cognitive impairment are not yet comprehensively known. Thus, we aimed to investigate cortical thickness differences in patients with myelin oligodendrocyte glycoprotein antibody-associated disease compared with HC. 3-Tesla brain magnetic resonance imaging was performed in 23 patients with myelin oligodendrocyte glycoprotein antibody-associated disease and 49 HC for voxel-wise group comparisons and neuropsychological testing in patients. Surface-based morphometry with region of interest-based surface analysis and region of interest-based extraction of cortical thickness was performed in patients compared with HC and in patient subgroups with and without cognitive impairment. Comparing patients with myelin oligodendrocyte glycoprotein antibody-associated disease with HC, exploratory surface-based morphometry demonstrated cortical volume reduction in pericalcarine and lingual cortical regions. Region of interest-based surface analysis specified reduced cortical thickness in the adjacent pericalcarine and orbitofrontal regions in myelin oligodendrocyte glycoprotein antibody-associated disease, as well as reduced temporal cortical thickness in patients with cognitive impairment (n = 10). Patients without cognitive impairment (n = 13) showed only circumscribed cortical brain volume loss compared with HC in the pericalcarine region. In conclusion, cortical atrophy in myelin oligodendrocyte glycoprotein antibody-associated disease was characterized by cortical thickness reduction in the adjacent pericalcarine and orbitofrontal regions, with a tendency of temporal thickness reduction in cognitively impaired patients.

Alternative Venous Pathways: A Potential Key Imaging Feature for Early Diagnosis of Sturge-Weber Syndrome Type 1.

Sturge-Weber syndrome is a rare congenital disorder characterized by cortical atrophy and calcifications on late-stage imaging. Understanding the evolution of brain lesions is crucial for effective early interventions, yet the timeline remains unclear. We aimed to evaluate early brain MRI findings and their progression longitudinally on follow up MRI in children diagnosed with Sturge-Weber syndrome. We retrospectively included all children with a confirmed diagnosis of Sturge-Weber syndrome between 2009 and 2023 that had at least 2 available MRIs performed before the age of 2 years. A pediatric radiologist and a pediatric neuroradiologist evaluated all the MRI scans for pial enhancement, choroid plexus enlargement, atrophy, calcifications, a prominent subarachnoid varicose network, trans medullary veins, subependymal veins, and deep extra ventricular veins. Descriptive analysis was used for demographic data and brain lesion prevalence. Cumulative incidence curves were used to show the timeline of emerging lesions. K-means clustering was used to categorize the lesions based on their prevalence at 1, 2, 3, 6, 12, 18, and 24 months after birth. Nine patients met the inclusion criteria. Median ages at the first and last MRIs were 35 days (IQR: 11-123) and 294 days (IQR: 208-465), respectively. The most prevalent lesions at the first MRI were subarachnoid varicose network (88.9%) and trans medullary veins (77.8%), while prevalence of atrophy and calcifications differed most between the first and last MRIs. The results of the elbow method and K-means clustering showed that we can divide Sturge-Weber syndrome lesions into 3 groups based on their timeline of emergence. The first cluster contained subarachnoid varicose network, trans medullary veins, subependymal veins, and choroid plexus enlargement. The second cluster contained deep extra ventricular veins, pial enhancement, accelerated myelination, and atrophy. The last cluster contained calcifications. Our findings suggest that dilated venous channels emerge early as a compensatory mechanism, preceding atrophy and calcification. Additionally, these dilated channels precede the appearance of abnormal contrast enhancement of the pia, often termed leptomeningeal angioma. This underscores the importance of early recognition and monitoring of these initial imaging indicators in clinical practice. ASL = Arterial Spin Labelled; MinIP = Minimum intensity projection; SWS = Sturge-Weber Syndrome.

Neuroimaging Findings in Children with Cerebral Palsy – Risk Assessment for Symptomatic Epilepsy

Neuroimaging plays a key role in the diagnosis of cerebral palsy (CP), as it helps to understand the etiology and pathogenesis of neurological impairment. The aim of the study is to demonstrate the role of neuroimaging in assessing the risk for epilepsy in children with CP with various lesions in CT and MRI with a focus on neuroimaging findings in full-term and premature children and their risk for epilepsy. The study includes 521 children with CP, diagnosed in the Clinic of Child Neurology, UMHATNP “St. Naum” between 2008 and 2018. Two hundred and twenty children underwent MRI of the brain, 464 of the cases had CT, and 127 had both MRI and CT. Various pathological lesions in MRI (brain malformations, lesions in the white or gray matter, lesions in the basal ganglia, cystic lesions, cortical atrophy, ventriculomegaly) were found in all patients with CP and symptomatic epilepsy, while 5.8% of those children with CP without epilepsy had normal MRI. Normal findings were observed in CT in 7.5% of the children with CP and epilepsy, while this result reached 12.1% when children did not have epilepsy. Among the abnormal findings in MRI with the highest relative risk for symptomatic epilepsy were ventriculomegaly RR – 1.296 (95% CI 1.149–1.463), cortical atrophy RR – 1.235 (95% CI 1.082–1.410) and lesions in the gray matter RR – 1.210 (95% CI 1.056–1.387). When comparing the types of the lesions in MRI in full-term and premature children with CP, we observed that white matter lesions predominated in premature children, while grey matter lesions in full-term children, which explains the higher incidence of epilepsy in full-term children. We found a higher incidence of pathological lesions in neuroimaging studies in patients with CP and concomitant epilepsy compared to those without epilepsy, as well as a high relative risk for epilepsy in patients with ventriculomegaly, cortical atrophy, and gray matter lesions.

Disparate and shared transcriptomic signatures associated with cortical atrophy in genetic bvFTD.

Cortical atrophy in behavioral variant frontotemporal degeneration (bvFTD) exhibits spatial heterogeneity across genetic subgroups, potentially driven by distinct biological mechanisms. Using an integrative imaging-transcriptomics approach, we identified disparate and shared transcriptomic signatures associated with cortical thickness in C9orf72 , GRN or MAPT -related bvFTD. Genes associated with cortical thinning in GRN -bvFTD were implicated in neurotransmission, further supported by mapping synaptic density maps to cortical thickness maps. Previously identified genes linked to TDP-43 positive neurons were significantly overlapped with genes associated with C9orf72 -bvFTD and GRN -bvFTD, but not MAPT -bvFTD providing specificity for our associations. C9orf72 -bvFTD and GRN -bvFTD shared genes displaying consistent directionality of correlations with cortical thickness, while MAPT -bvFTD displayed more pronounced differences in transcriptomic signatures with opposing directionality. Overall, we identified disparate and shared genes tied to regional vulnerability with increased biological interpretation including overlap with synaptic density maps and pathologically-specific gene expression, illuminating intricate molecular underpinnings contributing to heterogeneities in bvFTD.

Methods for assessment of rey auditory verbal learning test performance in memory clinic patients and healthy adults - at the cross-roads of learning theory and clinical utility

Background: Knowledge is still lacking regarding the preferred method for evaluation of learning in the Rey Auditory Verbal Learning Test (RAVLT). Validity of different methods was examined by the effect size in differentiating diagnostic stages in memory clinic patients versus healthy adults and the strength of association between RAVLT performance and brain atrophy. Method: The study included individuals with dementia (n = 247), Mild Cognitive Impairment (MCI, n = 709), Subjective Cognitive Impairment (SCI, n = 175) and cognitively unimpaired adults serving as healthy controls (HC, n = 102). All patients went through a comprehensive clinical examination and neuropsychological assessment of cognition including episodic memory gauged with RAVLT and brain imaging of medial temporal atrophy, cortical atrophy, and white matter hyperintensity. Results: The standard method for evaluation of learning in RAVLT (summed score over five trials) together with the late learning method (mean of trials 4 and 5) were the two most powerful methods according to group differentiation (discriminant validity). Both methods also showed considerable association with medial temporal atrophy (construct validity). The initial RAVLT performance represented by results on trial 1 and the constant in regression analysis with the power function provided information regarding attention that was important for the separation of SCI and HC. Conclusions: The most favorable clinical utility was indicated by discriminant and construct validity by total learning (standard method) including both attention- and learning-related parts and late learning of RAVLT performance, while theoretical understanding of mental processes involved in RAVLT performance was provided by the distinction between initial versus the subsequent learning performance.

The relationship between work difficulties and physical disability, cognitive and social cognitive impairment and subcortical gray matter atrophy in persons with multiple sclerosis.

Multiple sclerosis (MS) is commonly associated with work difficulties. This study aimed to examine the relationship between work difficulties and physical disability, cognitive and social cognitive impairment, and subcortical gray matter (scGM) atrophy in pwMS. Thirty-three employees with MS underwent assessments with Multiple Sclerosis Work Difficulties Questionnaire-23 MSWDQ-23. Physical disability was measured using EDSS, Timed 25-Foot Walk (T25FW), 2-Minute Walking Test (2-MWT), the Nine-Hole Peg test (N-HPT), and 12-item Multiple Sclerosis Walking Scale (MSWS-12). Cognitive functions were evaluated with Brief International Cognitive Assessment in MS (BICAMS), social cognition with Facial Emotion Identification (FEI), Reading the Mind in the Eyes Test (RMET), and Empathy Quotient (EQ). Anxiety and depression were assessed using Hospital Anxiety and Depression Scale (HADS). The association between variables was analysed using Spearman's correlation coefficient. GM volumes were calculated from 3T MRI data using Freesurfer, their potential relationship with work difficulties were evaluated through a linear regression model. MSWDQ-23 was strongly correlated with T25FW and MSWS-12 (p < 0.01), moderately correlated with EDSS, 2MWT, HAD, BICAMS, and EQ (p < 0.05). According to the linear regression model the decrease in volumes of total GM and scGM, bilateral Thalamus, bilateral Hippocampus, left Putamen, and right Caudate related with the severity of work difficulties (R²=0.815, p = 0.25). This study provides valuable insights into the multifaceted nature of work difficulties experienced by pwMS. It suggests that not only physical disability but also other factors, such as mood, cognition, empathy, and cortical and subcortical gray matter atrophy may contribute to work difficulties among pwMS.

Prosopagnosia: face blindness and its relationship to neurological disorders

This study examines the neurological and neuropathological conditions, and clinical, imaging, and demographic traits linked to prosopagnosia. Out of 475 potential cases, 327 met criteria for probable or definite prosopagnosia. One patient had Niemann-Pick type C and another had a forkhead box G1 gene mutation; ten patients (80% male) had developmental prosopagnosia. Of 317 with acquired prosopagnosia, 228 had degenerative causes, primarily primary prosopagnosia syndrome, Alzheimer's disease dementia, posterior cortical atrophy, and semantic dementia. Non-degenerative cases often involved ischemic and hemorrhagic infarcts. Transient non-degenerative prosopagnosia, linked to hypoxic encephalopathy and migraines, improved over time. Degenerative prosopagnosia patients often showed temporal lobe involvement on PET scans, while non-degenerative patients had right temporal and occipital lobe lesions on MRI. Pathological findings included Alzheimer's, Lewy body disease, and frontotemporal lobar degeneration. Facial recognition loss spans various neurological illnesses.

Evaluation of Mild Cognitive Impairment through Perientorhinal/Hippocampal Imaging and Comprehensive Neuropsychological and Psychophysical Assessment.

Mild cognitive impairment (MCI) is a significant concern as it is a risk factor for AD progression, and early detection is vital in order to delay dementia onset and enable potential therapeutic interventions. Olfactory impairment is recognized as a predictive biomarker in neurodegenerative processes. The aims of this study were to explore the degree of entorhinal cortical atrophy (ERICA) and the severity of MCI symptoms; to analyze magnetic resonance imaging (MRI) results for the entorhinal cortex, parahippocampal gyrus, peri entorhinal cortex, and the cerebellar tentorium; and to perform a comprehensive neuropsychological and psychophysical assessment. The main results highlighted that in our sample-multidomain amnesic MCI patients with hyposmic symptomatology-we found that ERICA scores were associated with the severity of anxiety symptomatology. One possible hypothesis to explain this observation is that anxiety may contribute to neurodegenerative processes by inducing chronic stress and inflammation. Future research should consider the longitudinal development of neuropsychological scores, anxiety disorders, and brain atrophy to determine their potential predictive value for MCI progression. These findings suggest the importance of psychological factors in MCI progression and the utility of neuropsychological assessment alongside neuroimaging techniques for early detection and follow-up in MCI patients.

In vivo CRISPR base editing for treatment of Huntington's disease.

Huntington's disease (HD) is an inherited and ultimately fatal neurodegenerative disorder caused by an expanded polyglutamine-encoding CAG repeat within exon 1 of the huntingtin (HTT) gene, which produces a mutant protein that destroys striatal and cortical neurons. Importantly, a critical event in the pathogenesis of HD is the proteolytic cleavage of the mutant HTT protein by caspase-6, which generates fragments of the N-terminal domain of the protein that form highly toxic aggregates. Given the role that proteolysis of the mutant HTT protein plays in HD, strategies for preventing this process hold potential for treating the disorder. By screening 141 CRISPR base editor variants targeting splice elements in the HTT gene, we identified platforms capable of producing HTT protein isoforms resistant to caspase-6-mediated proteolysis via editing of the splice acceptor sequence for exon 13. When delivered to the striatum of a rodent HD model, these base editors induced efficient exon skipping and decreased the formation of the N-terminal fragments, which in turn reduced HTT protein aggregation and attenuated striatal and cortical atrophy. Collectively, these results illustrate the potential for CRISPR base editing to decrease the toxicity of the mutant HTT protein for HD.

A study of the correlation between gray matter atrophy in multiple sclerosis and impairment of cognitive function domains

Objective: To quantify cerebral cortical and deep gray matter atrophy in patients with multiple sclerosis (MS) and explore its correlation with impairment in domains of cognitive function. Methods: Twenty patients with MS and 16 healthy controls (HC) matched for age, sex, and education level were included. Using FreeSurfer software, based on 3D-MRI technology, the differences in cortical thickness and deep gray matter volume between the two groups were comparatively analyzed. A neuropsychological scale that included six domains of cognitive function was scored on both study groups to analyze the correlation between cortical thickness and volume of deep gray matter in MS patients with impairment in cognitive function domains. Results: Impairment in domains of cognitive function: cognitive impairment was present in 60% MS patients in this study, mainly manifesting as impairment of verbal memory, verbal fluency, visuospatial memory, and information processing speed function (all P<0.05). Of these, the majority had impaired visuospatial memory function (55.0%), and the least number of patients had impaired information processing speed (15.0%). Changes in cortical thickness: compared with the HC group, the MS group showed that cortical atrophy was mainly concentrated in the frontoparietal region, including significant thinning of cortical thickness in the left inferior parietal gyrus, right superior frontal gyrus, and the right superior parietal gyrus (all P<0.05). Among them, atrophy of the left inferior parietal gyrus was significantly positively correlated with the impairment of verbal memory, verbal fluency, and information processing speed (all P<0.05). There was a significant positive correlation between the right superior frontal gyrus atrophy and verbal memory, verbal fluency, and visuospatial memory impairment (all P<0.05). Changes in deep gray matter volume: compared with the HC group, deep gray matter volume in the MS group decreased significantly in the bilateral thalamus, bilateral putamen, bilateral pallidum (all P<0.01), and right nucleus accumbens (P<0.05). Among them, left thalamus atrophy was significantly positively correlated with visuospatial memory impairment (r=0.45, P=0.046), and left putamen atrophy was both significantly positively correlated with visuospatial memory (r=0.45, P=0.047) and information processing speed impairment (r=0.50, P=0.026). Conclusions: Early structural brain changes in MS are dominated by gray matter atrophy. Deep gray matter is more prominent than cortical atrophy.

Early cortical atrophy in REM sleep behavior disorder

IntroductionThe presence of cortical atrophy (focal or diffuse) prior to the development of symptoms of cognitive impairment could predict the earliest cases of neurodegenerative disease in patients with CRSD. We reviewed the usefulness of cranial CT and MRI as early markers of cortical atrophy in patients with RSBD at our center. Patients and methodsRetrospective observational descriptive analysis of patients diagnosed with RSBD from October 2012 to October 2022. All with cranial CT or MRI, evaluated by a neuroradiologist. Results54 patients were included, 21 women (38.88%), 33 men (61.12%), mean age at diagnosis of TCSR: 69.04 ± 12.625. Of the 54 patients, 44 (81.48%) had imaging tests consistent with their age, and 10 had atrophy greater than expected for their age. Of the 54 patients, 21 (38.88%) with a diagnosis of neurodegenerative disease, 33 (61.12%) persist as idiopathic, almost all with more than 5 years of evolution (range of 1 to 10 years of evolution without diagnosis). Of the 10 (18.52%) patients with greater atrophy, all were diagnosed with neurodegenerative disease (8 in 1 year, 2 in 8 years). ConclusionsAlmost half of our series have developed a neurodegenerative disease in the first 10 years of evolution. The majority of them presented global cortical atrophy measured by the GCA scale in the first year of diagnosis, without other neurological symptoms. Patients who did not show cortical atrophy at diagnosis have not yet developed the neurodegenerative disease in 10 years of evolution. In our experience, the absence of cortical atrophy on cranial MRI or CT (measured by scales such as GCA) at the diagnosis of CRST seems to predict slower progression cases. These data should be corroborated with larger series.

Visual Cortical Thickness Increases with Prolonged Artificial Vision Restoration.

The Argus II retinal prosthesis restores visual perception to late blind patients. It has been shown that structural changes occur in the brain due to late-onset blindness, including cortical thinning in visual regions of the brain. Following vision restoration, it is not yet known whether these visual regions are reinvigorated and regain a normal cortical thickness or retain the diminished thickness from blindness. We evaluated the cortical thicknesses of ten Argus II Retinal Prostheses patients, ten blind patients, and thirteen sighted participants. The Argus II patients on average had a thicker left Cuneus Cortex and Lateral Occipital Cortex relative to the blind patients. The duration of the Argus II use (time since implant in active users) significantly partially correlated with thicker visual cortical regions in the left hemisphere. Furthermore, in the two case studies (scanned before and after implantation), the patient with longer device use (44.5 months) had an increase in the cortical thickness of visual regions, whereas the shorter-using patient did not (6.5 months). Finally, a third case, scanned at three time points post-implantation, showed an increase in cortical thickness in the Lateral Occipital Cortex between 43.5 and 57 months, which was maintained even after 3 years of disuse (106 months). Overall, the Argus II patients' cortical thickness was on average significantly rejuvenated in two higher visual regions and, patients using the implant for a longer duration had thicker visual regions. This research raises the possibility of structural plasticity reversing visual cortical atrophy in late-blind patients with prolonged vision restoration.