3 recherche sur le mot-clé 'Tract-based spatial statistics'

Age-related differences in white matter diffusion measures in autism spectrum condition / Abigail THOMPSON in Molecular Autism, 11 (2020)  

Public ISBD [article]  inMolecular Autism > 11 (2020) . - 36 p. Titre : Age-related differences in white matter diffusion measures in autism spectrum condition Type de document : Texte imprimé et/ou numérique Auteurs : Abigail THOMPSON, Auteur ; Asal SHAHIDIANI, Auteur ; Anne FRITZ, Auteur ; Jonathan O'MUIRCHEARTAIGH, Auteur ; Lindsay WALKER, Auteur ; Vera D'ALMEIDA, Auteur ; Clodagh M. MURPHY, Auteur ; Eileen DALY, Auteur ; Declan MURPHY, Auteur ; Steve WILLIAMS, Auteur ; Sean DEONI, Auteur ; Christine ECKER, Auteur Article en page(s) : 36 p. Langues : Anglais (eng) Mots-clés : Autism  Connectivity  Diffusion weighted imaging  Tract-based spatial statistics Index. décimale : PER Périodiques Résumé : BACKGROUND: Autism spectrum condition (ASC) is accompanied by developmental differences in brain anatomy and connectivity. White matter differences in ASC have been widely studied with diffusion imaging but results are heterogeneous and vary across the age range of study participants and varying methodological approaches. To characterize the neurodevelopmental trajectory of white matter maturation, it is necessary to examine a broad age range of individuals on the autism spectrum and typically developing controls, and investigate age × group interactions. METHODS: Here, we employed a spatially unbiased tract-based spatial statistics (TBSS) approach to examine age-related differences in white matter connectivity in a sample of 41 individuals with ASC, and 41 matched controls between 7-17 years of age. RESULTS: We found significant age-related differences between the ASC and control group in widespread brain regions. This included age-related differences in the uncinate fasciculus, corticospinal tract, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, anterior thalamic radiation, superior longitudinal fasciculus and forceps major. Measures of fractional anisotropy (FA) were significantly positively associated with age in both groups. However, this relationship was significantly stronger in the ASC group relative to controls. Measures of radial diffusivity (RD) were significantly negatively associated with age in both groups, but this relationship was significantly stronger in the ASC group relative to controls. LIMITATIONS: The generalisability of our findings is limited by the restriction of the sample to right-handed males with an IQ > 70. Furthermore, a longitudinal design would be required to fully investigate maturational processes across this age group. CONCLUSIONS: Taken together, our findings suggest that autistic males have an altered trajectory of white matter maturation relative to controls. Future longitudinal analyses are required to further characterize the extent and time course of these differences. En ligne : http://dx.doi.org/10.1186/s13229-020-00325-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=427 [article] Age-related differences in white matter diffusion measures in autism spectrum condition [Texte imprimé et/ou numérique] / Abigail THOMPSON, Auteur ; Asal SHAHIDIANI, Auteur ; Anne FRITZ, Auteur ; Jonathan O'MUIRCHEARTAIGH, Auteur ; Lindsay WALKER, Auteur ; Vera D'ALMEIDA, Auteur ; Clodagh M. MURPHY, Auteur ; Eileen DALY, Auteur ; Declan MURPHY, Auteur ; Steve WILLIAMS, Auteur ; Sean DEONI, Auteur ; Christine ECKER, Auteur . - 36 p. Langues : Anglais (eng) in Molecular Autism > 11 (2020) . - 36 p. Mots-clés : Autism  Connectivity  Diffusion weighted imaging  Tract-based spatial statistics Index. décimale : PER Périodiques Résumé : BACKGROUND: Autism spectrum condition (ASC) is accompanied by developmental differences in brain anatomy and connectivity. White matter differences in ASC have been widely studied with diffusion imaging but results are heterogeneous and vary across the age range of study participants and varying methodological approaches. To characterize the neurodevelopmental trajectory of white matter maturation, it is necessary to examine a broad age range of individuals on the autism spectrum and typically developing controls, and investigate age × group interactions. METHODS: Here, we employed a spatially unbiased tract-based spatial statistics (TBSS) approach to examine age-related differences in white matter connectivity in a sample of 41 individuals with ASC, and 41 matched controls between 7-17 years of age. RESULTS: We found significant age-related differences between the ASC and control group in widespread brain regions. This included age-related differences in the uncinate fasciculus, corticospinal tract, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, anterior thalamic radiation, superior longitudinal fasciculus and forceps major. Measures of fractional anisotropy (FA) were significantly positively associated with age in both groups. However, this relationship was significantly stronger in the ASC group relative to controls. Measures of radial diffusivity (RD) were significantly negatively associated with age in both groups, but this relationship was significantly stronger in the ASC group relative to controls. LIMITATIONS: The generalisability of our findings is limited by the restriction of the sample to right-handed males with an IQ > 70. Furthermore, a longitudinal design would be required to fully investigate maturational processes across this age group. CONCLUSIONS: Taken together, our findings suggest that autistic males have an altered trajectory of white matter maturation relative to controls. Future longitudinal analyses are required to further characterize the extent and time course of these differences. En ligne : http://dx.doi.org/10.1186/s13229-020-00325-6 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=427

Neurite orientation dispersion and density imaging reveals white matter microstructural alterations in adults with autism / C. ANDICA in Molecular Autism, 12 (2021)  

Public ISBD [article]  inMolecular Autism > 12 (2021) . - 48 p. Titre : Neurite orientation dispersion and density imaging reveals white matter microstructural alterations in adults with autism Type de document : Texte imprimé et/ou numérique Auteurs : C. ANDICA, Auteur ; K. KAMAGATA, Auteur ; E. KIRINO, Auteur ; W. UCHIDA, Auteur ; R. IRIE, Auteur ; S. MURATA, Auteur ; S. AOKI, Auteur Article en page(s) : 48 p. Langues : Anglais (eng) Mots-clés : Autism  Diffusion tensor imaging  Linear discriminant analysis  Neurite orientation dispersion and density imaging  Neuroinflammation  Neuronal loss  Region-of-interest  Tract-based spatial statistics  White matter microstructure Index. décimale : PER Périodiques Résumé : BACKGROUND: Evidences suggesting the association between behavioral anomalies in autism and white matter (WM) microstructural alterations are increasing. Diffusion tensor imaging (DTI) is widely used to infer tissue microstructure. However, due to its lack of specificity, the underlying pathology of reported differences in DTI measures in autism remains poorly understood. Herein, we applied neurite orientation dispersion and density imaging (NODDI) to quantify and define more specific causes of WM microstructural changes associated with autism in adults. METHODS: NODDI (neurite density index [NDI], orientation dispersion index, and isotropic volume fraction [ISOVF]) and DTI (fractional anisotropy [FA], mean diffusivity [MD], axial diffusivity, and radial diffusivity [RD]) measures were compared between autism (N?=?26; 19 males and 7 females; 32.93?±?9.24 years old) and age- and sex-matched typically developing (TD; N?=?25; 17 males and 8 females; 34.43?±?9.02 years old) groups using tract-based spatial statistics and region-of-interest analyses. Linear discriminant analysis using leave-one-out cross-validation (LDA-LOOCV) was also performed to assess the discriminative power of diffusion measures in autism and TD. RESULTS: Significantly lower NDI and higher ISOVF, suggestive of decreased neurite density and increased extracellular free-water, respectively, were demonstrated in the autism group compared with the TD group, mainly in commissural and long-range association tracts, but with distinct predominant sides. Consistent with previous reports, the autism group showed lower FA and higher MD and RD when compared with TD group. Notably, LDA-LOOCV suggests that NDI and ISOVF have relatively higher accuracy (82%) and specificity (NDI, 84%; ISOVF, 88%) compared with that of FA, MD, and RD (accuracy, 67-73%; specificity, 68-80%). LIMITATIONS: The absence of histopathological confirmation limit the interpretation of our findings. CONCLUSIONS: Our results suggest that NODDI measures might be useful as imaging biomarkers to diagnose autism in adults and assess its behavioral characteristics. Furthermore, NODDI allows interpretation of previous findings on changes in WM diffusion tensor metrics in individuals with autism. En ligne : http://dx.doi.org/10.1186/s13229-021-00456-4 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=459 [article] Neurite orientation dispersion and density imaging reveals white matter microstructural alterations in adults with autism [Texte imprimé et/ou numérique] / C. ANDICA, Auteur ; K. KAMAGATA, Auteur ; E. KIRINO, Auteur ; W. UCHIDA, Auteur ; R. IRIE, Auteur ; S. MURATA, Auteur ; S. AOKI, Auteur . - 48 p. Langues : Anglais (eng) in Molecular Autism > 12 (2021) . - 48 p. Mots-clés : Autism  Diffusion tensor imaging  Linear discriminant analysis  Neurite orientation dispersion and density imaging  Neuroinflammation  Neuronal loss  Region-of-interest  Tract-based spatial statistics  White matter microstructure Index. décimale : PER Périodiques Résumé : BACKGROUND: Evidences suggesting the association between behavioral anomalies in autism and white matter (WM) microstructural alterations are increasing. Diffusion tensor imaging (DTI) is widely used to infer tissue microstructure. However, due to its lack of specificity, the underlying pathology of reported differences in DTI measures in autism remains poorly understood. Herein, we applied neurite orientation dispersion and density imaging (NODDI) to quantify and define more specific causes of WM microstructural changes associated with autism in adults. METHODS: NODDI (neurite density index [NDI], orientation dispersion index, and isotropic volume fraction [ISOVF]) and DTI (fractional anisotropy [FA], mean diffusivity [MD], axial diffusivity, and radial diffusivity [RD]) measures were compared between autism (N?=?26; 19 males and 7 females; 32.93?±?9.24 years old) and age- and sex-matched typically developing (TD; N?=?25; 17 males and 8 females; 34.43?±?9.02 years old) groups using tract-based spatial statistics and region-of-interest analyses. Linear discriminant analysis using leave-one-out cross-validation (LDA-LOOCV) was also performed to assess the discriminative power of diffusion measures in autism and TD. RESULTS: Significantly lower NDI and higher ISOVF, suggestive of decreased neurite density and increased extracellular free-water, respectively, were demonstrated in the autism group compared with the TD group, mainly in commissural and long-range association tracts, but with distinct predominant sides. Consistent with previous reports, the autism group showed lower FA and higher MD and RD when compared with TD group. Notably, LDA-LOOCV suggests that NDI and ISOVF have relatively higher accuracy (82%) and specificity (NDI, 84%; ISOVF, 88%) compared with that of FA, MD, and RD (accuracy, 67-73%; specificity, 68-80%). LIMITATIONS: The absence of histopathological confirmation limit the interpretation of our findings. CONCLUSIONS: Our results suggest that NODDI measures might be useful as imaging biomarkers to diagnose autism in adults and assess its behavioral characteristics. Furthermore, NODDI allows interpretation of previous findings on changes in WM diffusion tensor metrics in individuals with autism. En ligne : http://dx.doi.org/10.1186/s13229-021-00456-4 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=459

White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder / Miriam COOPER in Journal of Autism and Developmental Disorders, 44-11 (November 2014)  

Public ISBD [article]  inJournal of Autism and Developmental Disorders > 44-11 (November 2014) . - p.2742-2754 Titre : White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder Type de document : Texte imprimé et/ou numérique Auteurs : Miriam COOPER, Auteur ; Anita THAPAR, Auteur ; Derek K. JONES, Auteur Article en page(s) : p.2742-2754 Langues : Anglais (eng) Mots-clés : Diffusion MRI  ADHD  ASD  White matter  Tract-based spatial statistics  RESTORE Index. décimale : PER Périodiques Résumé : Traits of autism spectrum disorder (ASD) in children with attention-deficit/hyperactivity disorder (ADHD) have previously been found to index clinical severity. This study examined the association of ASD traits with diffusion parameters in adolescent males with ADHD (n = 17), and also compared WM microstructure relative to controls (n = 17). Significant associations (p 0.05, corrected) were found between fractional anisotropy/radial diffusivity and ASD trait severity (positive and negative correlations respectively), mostly in the right posterior limb of the internal capsule/corticospinal tract, right cerebellar peduncle and the midbrain. No case–control differences were found for the diffusion parameters investigated. This is the first report of a WM microstructural signature of autistic traits in ADHD. Thus, even in the absence of full disorder, ASD traits may index a distinctive underlying neurobiology in ADHD. En ligne : http://dx.doi.org/10.1007/s10803-014-2131-9 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=241 [article] White Matter Microstructure Predicts Autistic Traits in Attention-Deficit/Hyperactivity Disorder [Texte imprimé et/ou numérique] / Miriam COOPER, Auteur ; Anita THAPAR, Auteur ; Derek K. JONES, Auteur . - p.2742-2754. Langues : Anglais (eng) in Journal of Autism and Developmental Disorders > 44-11 (November 2014) . - p.2742-2754 Mots-clés : Diffusion MRI  ADHD  ASD  White matter  Tract-based spatial statistics  RESTORE Index. décimale : PER Périodiques Résumé : Traits of autism spectrum disorder (ASD) in children with attention-deficit/hyperactivity disorder (ADHD) have previously been found to index clinical severity. This study examined the association of ASD traits with diffusion parameters in adolescent males with ADHD (n = 17), and also compared WM microstructure relative to controls (n = 17). Significant associations (p 0.05, corrected) were found between fractional anisotropy/radial diffusivity and ASD trait severity (positive and negative correlations respectively), mostly in the right posterior limb of the internal capsule/corticospinal tract, right cerebellar peduncle and the midbrain. No case–control differences were found for the diffusion parameters investigated. This is the first report of a WM microstructural signature of autistic traits in ADHD. Thus, even in the absence of full disorder, ASD traits may index a distinctive underlying neurobiology in ADHD. En ligne : http://dx.doi.org/10.1007/s10803-014-2131-9 Permalink : https://www.cra-rhone-alpes.org/cid/opac_css/index.php?lvl=notice_display&id=241