88 results on '"Patel, Raihaan"'
Search Results
52. Larger Amygdala Volume Mediates the Association Between Prenatal Maternal Stress and Higher Levels of Externalizing Behaviors: Sex Specific Effects in Project Ice Storm
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Jones, Sherri Lee, primary, Dufoix, Romane, additional, Laplante, David P., additional, Elgbeili, Guillaume, additional, Patel, Raihaan, additional, Chakravarty, M. Mallar, additional, King, Suzanne, additional, and Pruessner, Jens C., additional
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- 2019
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53. Clinical, imaging genetics and deformation based morphometry study of longitudinal changes after surgery for intractable aggressive behaviour
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Gouveia, Flavia V., primary, Germann, Jürgen, additional, de Morais, Rosa M. C. B., additional, Fonoff, Erich T., additional, Hamani, Clement, additional, Alho, Eduardo Joaquim, additional, Brentani, Helena, additional, Martins, Ana Paula, additional, Devenyi, Gabriel, additional, Patel, Raihaan, additional, Steele, Christopher J., additional, Gramer, Robert, additional, Chakravarty, M. Mallar, additional, and Martinez, Raquel C. R., additional
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- 2019
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54. Longitudinally Mapping Childhood Socioeconomic Status Associations with Cortical and Subcortical Morphology
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McDermott, Cassidy L., primary, Seidlitz, Jakob, additional, Nadig, Ajay, additional, Liu, Siyuan, additional, Clasen, Liv S., additional, Blumenthal, Jonathan D., additional, Reardon, Paul Kirkpatrick, additional, Lalonde, François, additional, Greenstein, Deanna, additional, Patel, Raihaan, additional, Chakravarty, M. Mallar, additional, Lerch, Jason P., additional, and Raznahan, Armin, additional
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- 2018
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55. Heritability estimates of cortical anatomy:The influence and reliability of different estimation strategies
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Patel, Sejal, Patel, Raihaan, Park, Min Tae M., Masellis, Mario, Knight, Jo, Chakravarty, M. Mallar, Patel, Sejal, Patel, Raihaan, Park, Min Tae M., Masellis, Mario, Knight, Jo, and Chakravarty, M. Mallar
- Abstract
Twin study designs have been previously used to investigate the heritability of neuroanatomical measures, such as regional cortical volumes. Volume can be fractionated into surface area and cortical thickness, where both measures are considered to have independent genetic and environmental bases. Region of interest (ROI) and vertex-wise approaches have been used to calculate heritability of cortical thickness and surface area in twin studies. In our study, we estimate heritability using the Human Connectome Project magnetic resonance imaging dataset composed of healthy young twin and non-twin siblings (mean age of 29, sample size of 757). Both ROI and vertex-wise methods were used to compare regional heritability of cortical thickness and surface area. Heritability estimates were controlled for age, sex, and total ipsilateral surface area or mean cortical thickness. In both approaches, heritability estimates of cortical thickness and surface area were lower when accounting for average ipsilateral cortical thickness and total surface area respectively. When comparing both approaches at a regional level, the vertex-wise approach showed higher surface area and lower cortical thickness heritability estimates compared to the ROI approach. The calcarine fissure had the highest surface area heritability estimate (ROI: 44%, vertex-wise: 50%) and posterior cingulate gyrus had the highest cortical thickness heritability (ROI: 50%, vertex-wise 40%). We also observed that limitations in image processing and variability in spatial averaging errors based on regional size may make obtaining true estimates of cortical thickness and surface area challenging in smaller regions. It is important to identify which approach is best suited to estimate heritability based on the research hypothesis and the size of the regions being investigated.
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- 2018
56. MR‐based age‐related effects on the striatum, globus pallidus, and thalamus in healthy individuals across the adult lifespan.
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Tullo, Stephanie, Patel, Raihaan, Devenyi, Gabriel A., Salaciak, Alyssa, Bedford, Saashi A., Farzin, Sarah, Wlodarski, Nancy, Tardif, Christine L., Breitner, John C. S., and Chakravarty, M. Mallar
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GLOBUS pallidus , *THALAMUS , *MIDDLE age , *MAGNETIC resonance imaging , *CORPUS striatum - Abstract
While numerous studies have used magnetic resonance imaging (MRI) to elucidate normative age‐related trajectories in subcortical structures across the human lifespan, there exists substantial heterogeneity among different studies. Here, we investigated the normative relationships between age and morphology (i.e., volume and shape), and microstructure (using the T1‐weighted/T2‐weighted [T1w/T2w] signal ratio as a putative index of myelin and microstructure) of the striatum, globus pallidus, and thalamus across the adult lifespan using a dataset carefully quality controlled, yielding a final sample of 178 for the morphological analyses, and 162 for the T1w/T2w analyses from an initial dataset of 253 healthy subjects, aged 18–83. In accordance with previous cross‐sectional studies of adults, we observed age‐related volume decrease that followed a quadratic relationship between age and bilateral striatal and thalamic volumes, and a linear relationship in the globus pallidus. Our shape indices consistently demonstrated age‐related posterior and medial areal contraction bilaterally across all three structures. Beyond morphology, we observed a quadratic inverted U‐shaped relationship between T1w/T2w signal ratio and age, with a peak value occurring in middle age (at around 50 years old). After permutation testing, the Akaike information criterion determined age relationships remained significant for the bilateral globus pallidus and thalamus, for both the volumetric and T1w/T2w analyses. Our findings serve to strengthen and expand upon previous volumetric analyses by providing a normative baseline of morphology and microstructure of these structures to which future studies investigating patients with various disorders can be compared. [ABSTRACT FROM AUTHOR]
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- 2019
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57. Warping an atlas derived from serial histology to 5 high-resolution MRIs
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Tullo, Stephanie, primary, Devenyi, Gabriel A., additional, Patel, Raihaan, additional, Park, Min Tae M., additional, Collins, D. Louis, additional, and Chakravarty, M. Mallar, additional
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- 2018
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58. F6. Is it Possible to Elicit Progressive Functioning Decline Without Having Beta-Amyloid Pathology? Clinical Trajectories of Mild Cognitive Impairment With Suspected Non-Alzheimer's Pathology
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Chung, Jun Ku, primary, Plitman, Eric, additional, Nakajima, Shinichiro, additional, Caravaggio, Fernando, additional, Shinagawa, Shunichiro, additional, Iwata, Yusuke, additional, Gerretsen, Philip, additional, Kim, Julia, additional, Takeuchi, Hiroyoshi, additional, Patel, Raihaan, additional, Chakravarty, Mallar, additional, Strafella, Antonio, additional, and Graff-Guerrero, Ariel, additional
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- 2018
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59. F178. NEUROANATOMICAL PROFILES OF TREATMENT-RESISTANCE IN PATIENTS WITH SCHIZOPHRENIA
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Plitman, Eric, primary, Iwata, Yusuke, additional, Nakajima, Shinichiro, additional, Chung, Jun Ku, additional, Patel, Raihaan, additional, Caravaggio, Fernando, additional, Kim, Julia, additional, De Luca, Vincenzo, additional, Chavez, Sofia, additional, Remington, Gary, additional, Mallar Chakravarty, M, additional, Gerretsen, Philip, additional, and Graff-Guerrero, Ariel, additional
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- 2018
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60. Healthy versus Entorhinal Cortical Atrophy Identification in Asymptomatic APOE4 Carriers at Risk for Alzheimer’s Disease
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Konishi, Kyoko, primary, Joober, Ridha, additional, Poirier, Judes, additional, MacDonald, Kathleen, additional, Chakravarty, Mallar, additional, Patel, Raihaan, additional, Breitner, John, additional, and Bohbot, Véronique D., additional
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- 2018
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61. Normative Brain Size Variation and the Remodeling of Brain Shape in Humans
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Reardon, P. K., primary, Vandekar, Simon N., additional, Liu, Siyuan, additional, Patel, Raihaan, additional, Park, Min Tae M., additional, Alexander-Bloch, Aaron, additional, Seidlitz, Jakob, additional, Clasen, Liv S., additional, Blumenthal, Jonathan D., additional, Giedd, Jay N., additional, Gur, Ruben C., additional, Gur, Raquel E., additional, Lerch, Jason P., additional, Chakravarty, M. Mallar, additional, Satterthwaite, Theodore D., additional, Shinohara, Russel T., additional, and Raznahan, Armin, additional
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- 2017
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62. Association of monoamine oxidase-A genetic variants and amygdala morphology in violent offenders with antisocial personality disorder and high psychopathic traits
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Kolla, Nathan J., primary, Patel, Raihaan, additional, Meyer, Jeffrey H., additional, and Chakravarty, M. Mallar, additional
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- 2017
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63. The relationship between subcortical brain volume and striatal dopamine D2/3receptor availability in healthy humans assessed with [11C]-raclopride and [11C]-(+)-PHNO PET
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Caravaggio, Fernando, primary, Ku Chung, Jun, additional, Plitman, Eric, additional, Boileau, Isabelle, additional, Gerretsen, Philip, additional, Kim, Julia, additional, Iwata, Yusuke, additional, Patel, Raihaan, additional, Chakravarty, M. Mallar, additional, Remington, Gary, additional, and Graff-Guerrero, Ariel, additional
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- 2017
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64. Structural and Clinical Trajectories of Mild Cognitive Impairment with Suspected Non-Amyloid Pathology: A 2-Year Longitudinal Study
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Chung, Jun Ku, primary, Plitman, Eric, additional, Nakajima, Shinichiro, additional, Shinagawa, Shunichiro, additional, Iwata, Yusuke, additional, Gerretsen, Philip, additional, Caravaggio, Fernando, additional, Kim, Julia, additional, Patel, Raihaan, additional, Chakravarty, Mallar M., additional, and Graff-Guerrero, Ariel, additional
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- 2017
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65. Large-scale analyses of the relationship between sex, age and intelligence quotient heterogeneity and cortical morphometry in autism spectrum disorder
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Bedford, Saashi A., Park, Min Tae M., Devenyi, Gabriel A., Tullo, Stephanie, Germann, Jurgen, Patel, Raihaan, Anagnostou, Evdokia, Baron-Cohen, Simon, Bullmore, Edward T., Chura, Lindsay R., Craig, Michael C., Ecker, Christine, Floris, Dorothea L., Holt, Rosemary J., Lenroot, Rhoshel, Lerch, Jason P., Lombardo, Michael V., Murphy, Declan G. M., Raznahan, Armin, Ruigrok, Amber N. V., Smith, Elizabeth, Spencer, Michael D., Suckling, John, Taylor, Margot J., Thurm, Audrey, Lai, Meng-Chuan, and Chakravarty, M. Mallar
- Abstract
Significant heterogeneity across aetiologies, neurobiology and clinical phenotypes have been observed in individuals with autism spectrum disorder (ASD). Neuroimaging-based neuroanatomical studies of ASD have often reported inconsistent findings which may, in part, be attributable to an insufficient understanding of the relationship between factors influencing clinical heterogeneity and their relationship to brain anatomy. To this end, we performed a large-scale examination of cortical morphometry in ASD, with a specific focus on the impact of three potential sources of heterogeneity: sex, age and full-scale intelligence (FIQ). To examine these potentially subtle relationships, we amassed a large multi-site dataset that was carefully quality controlled (yielding a final sample of 1327 from the initial dataset of 3145 magnetic resonance images; 491 individuals with ASD). Using a meta-analytic technique to account for inter-site differences, we identified greater cortical thickness in individuals with ASD relative to controls, in regions previously implicated in ASD, including the superior temporal gyrus and inferior frontal sulcus. Greater cortical thickness was observed in sex specific regions; further, cortical thickness differences were observed to be greater in younger individuals and in those with lower FIQ, and to be related to overall clinical severity. This work serves as an important step towards parsing factors that influence neuroanatomical heterogeneity in ASD and is a potential step towards establishing individual-specific biomarkers.
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- 2020
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66. Longitudinally Mapping Childhood Socioeconomic Status Associations with Cortical and Subcortical Morphology.
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McDermott, Cassidy L., Seidlitz, Jakob, Nadig, Ajay, Siyuan Liu, Clasen, Liv S., Blumenthal, Jonathan D., Reardon, Paul Kirkpatrick, Lalonde, François, Greenstein, Deanna, Patel, Raihaan, Chakravarty, M. Mallar, Lerch, Jason P., and Raznahan, Armin
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SOCIAL status ,MORPHOLOGY ,CHILDREN ,SEXUAL selection - Abstract
Childhood socioeconomic status (SES) impacts cognitive development and mental health, but its association with human structural brain development is not yet well characterized. Here, we analyzed 1243 longitudinally acquired structural MRI scans from 623 youth (299 female/324 male) to investigate the relation between SES and cortical and subcortical morphology between ages 5 and 25 years. We found positive associations between SES and total volumes of the brain, cortical sheet, and four separate subcortical structures. These associations were stable between ages 5 and 25. Surface-based shape analysis revealed that higher SES is associated with areal expansion of lateral prefrontal, anterior cingulate, lateral temporal, and superior parietal cortices and ventrolateral thalamic, and medial amygdalo-hippocampal subregions. Meta-analyses of functional imaging data indicate that cortical correlates of SES are centered on brain systems subserving sensorimotor functions, language, memory, and emotional processing. We further show that anatomical variation within a subset of these cortical regions partially mediates the positive association between SES and IQ. Finally, we identify neuroanatomical correlates of SES that exist above and beyond accompanying variation in IQ. Although SES is clearly a complex construct that likely relates to development through diverse, nondeterministic processes, our findings elucidate potential neuroanatomical mediators of the association between SES and cognitive outcomes. [ABSTRACT FROM AUTHOR]
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- 2019
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67. The effect of crack cocaine addiction and age on the microstructure and morphology of the human striatum and thalamus using shape analysis and fast diffusion kurtosis imaging
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Garza-Villarreal, Eduardo A, primary, Mallar Chakravarty, M, additional, Hansen, Brian, additional, Eskildsen, Simon F, additional, Devenyi, Gabriel A., additional, Castillo-Padilla, Diana, additional, Balducci, Thania, additional, Reyes-Zamorano, Ernesto, additional, Jespersen, Sune N, additional, Perez-Palacios, Pamela, additional, Patel, Raihaan, additional, and Gonzalez-Olvera, Jorge J, additional
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- 2016
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68. F4-04-02: Interpreting Disease Heterogeneity in Alzheimer's and Parkinson's Disease
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Chakravarty, Mallar, primary, Amaral, Robert S.C., additional, Bhagwat, Nikhil, additional, Patel, Raihaan, additional, Garza-Villarreal, Eduardo, additional, Devenyi, Gabriel, additional, and Tae M Park, Min, additional
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- 2016
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69. Glutamatergic Metabolites, Volume and Cortical Thickness in Antipsychotic-Naive Patients with First-Episode Psychosis: Implications for Excitotoxicity
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Plitman, Eric, primary, Patel, Raihaan, additional, Chung, Jun Ku, additional, Pipitone, Jon, additional, Chavez, Sofia, additional, Reyes-Madrigal, Francisco, additional, Gómez-Cruz, Gladys, additional, León-Ortiz, Pablo, additional, Chakravarty, M Mallar, additional, de la Fuente-Sandoval, Camilo, additional, and Graff-Guerrero, Ariel, additional
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- 2016
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70. Healthy versus Entorhinal Cortical Atrophy Identification in Asymptomatic APOE4 Carriers at Risk for Alzheimer's Disease.
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Kyoko Konishi, Joober, Ridha, Poirier, Judes, MacDonald, Kathleen, Chakravarty, Mallar, Patel, Raihaan, Breitner, John, Bohbot, Véronique D., and Konishi, Kyoko
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ALZHEIMER'S disease diagnosis ,EARLY diagnosis ,APOLIPOPROTEIN E gene ,GRAY matter (Nerve tissue) ,ATROPHY ,MAGNETIC resonance imaging of the brain ,ENTORHINAL cortex ,ALLELES ,ALZHEIMER'S disease ,APOLIPOPROTEINS ,COMPARATIVE studies ,HIPPOCAMPUS (Brain) ,MAGNETIC resonance imaging ,RESEARCH methodology ,MEDICAL cooperation ,MEMORY ,RESEARCH ,RESEARCH funding ,TEMPORAL lobe ,EVALUATION research ,CASE-control method ,GENETIC carriers - Abstract
Early detection of Alzheimer's disease (AD) has been challenging as current biomarkers are invasive and costly. Strong predictors of future AD diagnosis include lower volume of the hippocampus and entorhinal cortex, as well as the ɛ4 allele of the Apolipoprotein E gene (APOE) gene. Therefore, studying functions that are critically mediated by the hippocampus and entorhinal cortex, such as spatial memory, in APOE ɛ4 allele carriers, may be key to the identification of individuals at risk of AD, prior to the manifestation of cognitive impairments. Using a virtual navigation task developed in-house, specifically designed to assess spatial versus non-spatial strategies, the current study is the first to differentiate functional and structural differences within APOE ɛ4 allele carriers. APOE ɛ4 allele carriers that predominantly use non-spatial strategies have decreased fMRI activity in the hippocampus and increased atrophy in the hippocampus, entorhinal cortex, and fimbria compared to APOE ɛ4 allele carriers who use spatial strategies. In contrast, APOE ɛ4 allele carriers who use spatial strategies have grey matter levels comparable to non-APOE ɛ4 allele carriers. Furthermore, in a leave-one-out analysis, grey matter in the entorhinal cortex could predict navigational strategy with 92% accuracy. [ABSTRACT FROM AUTHOR]
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- 2018
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71. The relationship between subcortical brain volume and striatal dopamine D2/3 receptor availability in healthy humans assessed with [11C]-raclopride and [11C]-(+)-PHNO PET.
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Caravaggio, Fernando, Ku Chung, Jun, Plitman, Eric, Boileau, Isabelle, Gerretsen, Philip, Kim, Julia, Iwata, Yusuke, Patel, Raihaan, Chakravarty, M. Mallar, Remington, Gary, and Graff ‐ Guerrero, Ariel
- Abstract
Background Abnormalities in dopamine (DA) and brain morphology are observed in several neuropsychiatric disorders. However, it is not fully understood how these abnormalities may relate to one another. For such in vivo findings to be used as biomarkers for neuropsychiatric disease, it must be understood how variability in DA relates to brain structure under healthy conditions. We explored how the availability of striatal DA D
2/3 receptors (D2/3 R) is related to the volume of subcortical brain structures in a sample of healthy humans. Differences in D2/3 R availability measured with an antagonist radiotracer ([11 C]-raclopride) versus an agonist radiotracer ([11 C]-(+)-PHNO) were examined. Methods Data from 62 subjects scanned with [11 C]-raclopride (mean age = 38.98 ± 14.45; 23 female) and 68 subjects scanned with [11 C]-(+)-PHNO (mean age = 38.54 ± 14.59; 25 female) were used. Subcortical volumes were extracted from T1-weighted images using the Multiple Automatically Generated Templates (MAGeT-Brain) algorithm. Partial correlations were used controlling for age, gender, and total brain volume. Results For [11 C]-(+)-PHNO, ventral caudate volumes were positively correlated with BPND in the dorsal caudate and globus pallidus (GP). Ventral striatum (VS) volumes were positively correlated with BPND in the VS. With [11 C]-raclopride, BPND in the VS was negatively correlated with subiculum volume of the hippocampus. Moreover, BPND in the GP was negatively correlated with the volume of the lateral posterior nucleus of the thalamus. Conclusion Findings are purely exploratory and presented corrected and uncorrected for multiple comparisons. We hope they will help inform the interpretation of future PET studies where concurrent changes in D2/3 R and brain morphology are observed. Hum Brain Mapp 38:5519-5534, 2017. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]- Published
- 2017
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72. Poster Number: NR 7 - Structural and Clinical Trajectories of Mild Cognitive Impairment with Suspected Non-Amyloid Pathology: A 2-Year Longitudinal Study
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Chung, Jun Ku, Plitman, Eric, Nakajima, Shinichiro, Shinagawa, Shunichiro, Iwata, Yusuke, Gerretsen, Philip, Caravaggio, Fernando, Kim, Julia, Patel, Raihaan, Chakravarty, Mallar M., and Graff-Guerrero, Ariel
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- 2017
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73. The Effects of Cortical Hypometabolism and Hippocampal Atrophy on Clinical Trajectories in Mild Cognitive Impairment with Suspected Non-Alzheimer's Pathology: A Brief Report.
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Chung, Jun Ku, Plitman, Eric, Nakajima, Shinichiro, Caravaggio, Fernando, Shinagawa, Shunichiro, Iwata, Yusuke, Gerretsen, Philip, Kim, Julia, Takeuchi, Hiroyoshi, Patel, Raihaan, Chakravarty, M Mallar, Strafella, Antonio, Graff-Guerrero, Ariel, and Alzheimer’s Disease Neuroimaging Initiative
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The clinical and structural trajectories of suspected non-Alzheimer' pathology (SNAP) remain elusive due to its heterogeneous etiology. Baseline and longitudinal clinical (global cognition, daily functioning, symptoms of dementia, and learning memory) and hippocampal volume trajectories over two years were compared between patients with amnestic mild cognitive impairment (aMCI) with SNAP with reduced hippocampal volumes (SNAP+HIPPO) and aMCI patients with SNAP without reduced hippocampal volumes. SNAP+HIPPO showed overall worse baseline cognitive functions. Longitudinally, SNAP+HIPPO showed faster deterioration of clinical symptoms of dementia. Having both hippocampal atrophy and cortical hypometabolism without amyloid pathology may exacerbate symptoms of dementia in aMCI. [ABSTRACT FROM AUTHOR]
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- 2017
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74. Your algorithm might think the hippocampus grows in Alzheimer's disease: Caveats of longitudinal automated hippocampal volumetry.
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Sankar, Tejas, Park, Min Tae M., Jawa, Tasha, Patel, Raihaan, Bhagwat, Nikhil, Voineskos, Aristotle N., Lozano, Andres M., and Chakravarty, M. Mallar
- Abstract
Hippocampal atrophy rate-measured using automated techniques applied to structural MRI scans-is considered a sensitive marker of disease progression in Alzheimer's disease, frequently used as an outcome measure in clinical trials. Using publicly accessible data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we examined 1-year hippocampal atrophy rates generated by each of five automated or semiautomated hippocampal segmentation algorithms in patients with Alzheimer's disease, subjects with mild cognitive impairment, or elderly controls. We analyzed MRI data from 398 and 62 subjects available at baseline and at 1 year at MRI field strengths of 1.5 T and 3 T, respectively. We observed a high rate of hippocampal segmentation failures across all algorithms and diagnostic categories, with only 50.8% of subjects at 1.5 T and 58.1% of subjects at 3 T passing stringent segmentation quality control. We also found that all algorithms identified several subjects (between 2.94% and 48.68%) across all diagnostic categories showing increases in hippocampal volume over 1 year. For any given algorithm, hippocampal 'growth' could not entirely be explained by excluding patients with flawed hippocampal segmentations, scan-rescan variability, or MRI field strength. Furthermore, different algorithms did not uniformly identify the same subjects as hippocampal 'growers,' and showed very poor concordance in estimates of magnitude of hippocampal volume change over time (intraclass correlation coefficient 0.319 at 1.5 T and 0.149 at 3 T). This precluded a meaningful analysis of whether hippocampal 'growth' represents a true biological phenomenon. Taken together, our findings suggest that longitudinal hippocampal volume change should be interpreted with considerable caution as a biomarker. Hum Brain Mapp 38:2875-2896, 2017. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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75. Hippocampal and Clinical Trajectories of Mild Cognitive Impairment with Suspected Non-Alzheimer's Disease Pathology.
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Jun Ku Chung, Eric Plitman, Shinichiro Nakajima, Fernando Caravaggio, Yusuke Iwata, Gerretsen, Philip, Kim, Julia, Hiroyoshi Takeuchi, Shunichiro Shinagawa, Patel, Raihaan, Chakravarty, M. Mallar, Graff-Guerrero, Ariel, Chung, Jun Ku, Plitman, Eric, Nakajima, Shinichiro, Caravaggio, Fernando, Iwata, Yusuke, Takeuchi, Hiroyoshi, Shinagawa, Shunichiro, and Alzheimer’s Disease Neuroimaging Initiative
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MILD cognitive impairment ,NEURODEGENERATION ,AMYLOID ,HIPPOCAMPUS (Brain) ,PATHOLOGY ,PROTEIN metabolism ,ALZHEIMER'S disease ,ANTHROPOMETRY ,APOLIPOPROTEINS ,COGNITION ,LONGITUDINAL method ,MAGNETIC resonance imaging ,POSITRON emission tomography ,ACTIVITIES of daily living ,DISEASE progression - Abstract
Suspected non-Alzheimer's disease pathology (SNAP) characterizes individuals showing neurodegeneration (e.g., hypometabolism) without amyloid-β (Aβ). Findings from previous studies regarding clinical and structural trajectories of SNAP are inconsistent. Using data from the Alzheimer's Disease Neuroimaging Initiative, patients with amnestic mild cognitive impairment (MCI) were categorized into four groups: amyloid positive with hypometabolism (Aβ+ND+), amyloid only (Aβ+ND-), neither amyloid nor hypometabolism (Aβ-ND-), and SNAP (Aβ-ND+). Aβ+ND+(n = 33), Aβ+ND-(n = 32), and Aβ-ND-(n = 36) were matched to SNAP for age, gender, apolipoprotein E4 (apoE4) genotype, and scores on the Montreal Cognitive Assessment. Elderly controls (n = 40) were also matched to SNAP for age, gender, and apoE4 genotype. Longitudinal changes were compared across groups in terms of hippocampal volume, clinical symptoms, daily functioning, and cognitive functioning over a 2-year period. At baseline, no difference in cognition and functioning was observed between SNAP and Aβ+groups. SNAP showed worse clinical symptoms and impaired functioning at baseline compared to Aβ-ND-and controls. Two years of follow-up showed no differences in hippocampal volume changes between SNAP and any of the comparison groups. SNAP showed worse functional deterioration in comparison to Aβ-ND-and controls. However, Aβ+ND+ showed more severe changes in clinical symptoms in comparison to SNAP. Thus, patients with MCI and SNAP showed 1) more severe functional deterioration compared to Aβ-ND-and controls, 2) no differences with Aβ+ND-, and 3) less cognitive deterioration than Aβ+ND+. Future studies should investigate what causes SNAP, which is different from typical AD pathology and biomarker cascades. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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76. Depressive Symptoms and Small Hippocampal Volume Accelerate the Progression to Dementia from Mild Cognitive Impairment.
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Jun Ku Chung, Plitman, Eric, Shinichiro Nakajima, Mallar Chakravarty, M., Caravaggio, Fernando, Hiroyoshi Takeuchi, Gerretsen, Philip, Yusuke Iwata, Patel, Raihaan, Mulsant, Benoit H., Graff-Guerrero, Ariel, Chung, Jun Ku, Nakajima, Shinichiro, Chakravarty, M Mallar, Takeuchi, Hiroyoshi, and Iwata, Yusuke
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HIPPOCAMPUS diseases ,MILD cognitive impairment ,DIAGNOSIS of dementia ,DIAGNOSIS methods ,LONGITUDINAL method ,DEPRESSION in adolescence ,DIAGNOSIS ,COGNITION disorders ,DEMENTIA ,MENTAL depression ,HIPPOCAMPUS (Brain) ,DIGITAL image processing ,MAGNETIC resonance imaging ,RESEARCH funding ,DISEASE progression ,GERIATRIC Depression Scale - Abstract
Previous studies have highlighted that decreased hippocampal volume, an early neural correlate of dementia, is commonly observed in patients with mild cognitive impairment (MCI). However, it is unclear whether neurodegenerative and resultant clinical trajectories are accelerated in MCI patients with concomitant depressive symptoms, leading to a faster conversion to dementia stages than those who are not depressed. No longitudinal study has investigated whether depressed amnestic MCI (DEP+aMCI) patients show an earlier onset of progression to dementia than non-depressed amnestic MCI (DEP-aMCI) patients and whether progressive hippocampal volume reductions are related in the conversion process. Using data from Alzheimer's Disease Neuroimaging Initiative, we examined 2-year follow-up data from 38 DEP+aMCI patients and 38 matched DEP-aMCI patients and compared their ages of conversion from aMCI to AD and trajectories of progressive hippocampal volume changes. DEP+ and DEP- patients were defined as having baseline Geriatric Depression Scale scores of 5 or above and 0, respectively. DEP+ converters showed earlier ages of conversion to dementia (p = 0.009) and greater left hippocampal volume loss than both DEP- converters and DEP+ non-converters over the 2-year period (p = 0.003, p = 0.001, respectively). These findings could not be explained by changes in total brain volume, differences in their clinical symptoms of dementia, daily functioning, or apolipoprotein E4 genotypes. No difference in conversion rate to dementia or progressive hippocampal volume change was found between DEP+ patients and DEP-patients, which suggested depressive symptoms themselves may not lead to progression of dementia from MCI. In conclusion, there is a synergistic effect of depressive symptoms and smaller left hippocampal volume in MCI patients that accelerates conversion to dementia. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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77. Development and validation of a dementia risk score in the UK Biobank and Whitehall II cohorts
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Anatu¨rk, Melis, Patel, Raihaan, Ebmeier, Klaus P., Georgiopoulos, Georgios, Newby, Danielle, Topiwala, Anya, de Lange, Ann-Marie G, Cole, James H, Jansen, Michelle G, Singh-Manoux, Archana, Kivima¨ki, Mika, and Suri, Sana
- Abstract
BackgroundCurrent dementia risk scores have had limited success in consistently identifying at-risk individuals across different ages and geographical locations.ObjectiveWe aimed to develop and validate a novel dementia risk score for a midlife UK population, using two cohorts: the UK Biobank, and UK Whitehall II study.MethodsWe divided the UK Biobank cohort into a training (n=176 611, 80%) and test sample (n=44 151, 20%) and used the Whitehall II cohort (n=2934) for external validation. We used the Cox LASSO regression to select the strongest predictors of incident dementia from 28 candidate predictors and then developed the risk score using competing risk regression.FindingsOur risk score, termed the UK Biobank Dementia Risk Score (UKBDRS), consisted of age, education, parental history of dementia, material deprivation, a history of diabetes, stroke, depression, hypertension, high cholesterol, household occupancy, and sex. The score had a strong discrimination accuracy in the UK Biobank test sample (area under the curve (AUC) 0.8, 95% CI 0.78 to 0.82) and in the Whitehall cohort (AUC 0.77, 95% CI 0.72 to 0.81). The UKBDRS also significantly outperformed three other widely used dementia risk scores originally developed in cohorts in Australia (the Australian National University Alzheimer’s Disease Risk Index), Finland (the Cardiovascular Risk Factors, Ageing, and Dementia score), and the UK (Dementia Risk Score).Clinical implicationsOur risk score represents an easy-to-use tool to identify individuals at risk for dementia in the UK. Further research is required to determine the validity of this score in other populations.
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- 2023
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78. INVESTIGATING STRUCTURAL CONNECTIVITY CORRELATES OF VERBAL MEMORY DEFICITS AMONG FIRST-EPISODE PSYCHOSIS PATIENTS.
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Henri-Bellemare, Charlie, Patel, Raihaan, Lavigne, Katie, Chakravarty, M. Mallar, and Lepage, Martin
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CONFERENCES & conventions ,MAGNETIC resonance imaging ,MEMORY ,MEMORY disorders ,PSYCHOSES ,DISEASE risk factors - Abstract
Background: Verbal memory is one of the most affected cognitive domains in patients with schizophrenia and related psychoses. Several studies have found associations between cognitive abilities and white matter fractional anisotropy (FA) in schizophrenia; however, only a few tractography studies have investigated FA relative to verbal memory in patients with a first episode of psychosis (FEP) compared with healthy controls (HC). Although white matter tractography differences have been well established between chronic patients and HC, the direction of findings from FEP studies has been inconsistent. Thus, the present study aims to examine wholebrain white matter differences and its association with verbal memory in individuals with a FEP relative to HC using tractography. Methods: Diffusion-weighted images were acquired on a 1.5T scanner for patients (n=65) and controls (n=54) at baseline. The Wechsler Memory Scale was used as a measure of verbal memory. Pre-processing was performed on a subject-by-subject basis using MRtrix. Diffusion tractography was generated using a probabilistic anatomically-constrained tractography algorithm, which constrains the reconstruction to specific biological priors. Furthermore, the spherical-deconvolution informed filtering of tractograms (SIFT) tool will be used to ensure the tractogram is biologically meaningful. This results in subject-specific connectomes defining the mean FA between two regions of interest that were defined using the Desikan- Killiany atlas. A linear model was used to test for main effect of group and main effect of verbal memory on white matter tract FA, covarying for age and sex. For both sets of analyses, results were corrected for multiple comparisons using false discovery rate (FDR). Results: A significant main effect of group on whole-brain average FA was observed, with patients displaying lower average FA compared to healthy controls (Patients=0.291, controls=0.300, p<0.05). Whole-brain white matter tract FA analysis revealed that there are widespread differences between controls and individuals with a FEP. Group most strongly predicted white matter tract FA differences between left caudal anterior cingulate and left lateral orbitofrontal (patients mean FA=0.302, controls mean FA=0.342), left hippocampus and right isthmus cingulate (patient mean FA= 0.217 controls mean FA= 0.318), and finally left lingual and left rostral anterior cingulate (patients mean FA=0.162, controls mean FA= 0.249. However, none survived correction for multiple comparisons. Further, there was no significant association between verbal memory and white matter tract FA in FEP or HC. Discussion: Findings from this study suggest there are some significant differences in whole-brain average FA between individuals experiencing a FEP and healthy controls. However, when analyzing whole-brain tract FA, none of the connections survived corrections for multiple comparisons. These findings might be limited by the scanner resolution included in this study, which may not capture more subtle differences. Nonetheless, these results are consistent with a cross-sectional study comparing healthy individuals to chronic and first-episode patients suggesting that modest differences are present early in the disease and increase as the disease progresses. We suggest that future studies analyze white matter tract using a longitudinal design to identify disease progression. [ABSTRACT FROM AUTHOR]
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- 2020
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79. Greater cortical thickness in individuals with ASD
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Bedford, Saashi A., Park, Min Tae M., Devenyi, Gabriel A., Tullo, Stephanie, Germann, Jurgen, Patel, Raihaan, Anagnostou, Evdokia, Baron-Cohen, Simon, Bullmore, Edward T., Chura, Lindsay R., Craig, Michael C., Ecker, Christine, Floris, Dorothea L., Holt, Rosemary J., Lenroot, Rhoshel, Lerch, Jason P., Lombardo, Michael V., Murphy, Declan G. M., Raznahan, Armin, Ruigrok, Amber N. V., Smith, Elizabeth, Spencer, Michael D., Suckling, John, Taylor, Margot J., Thurm, Audrey, Lai, Meng-Chuan, and Chakravarty, M. Mallar
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- 2020
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80. A Multi-Modal MRI Analysis of Cortical Structure in Relation to Gender Dysphoria, Sexual Orientation, and Age in Adolescents
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Skorska, Malvina N, Chavez, Sofia, Devenyi, Gabriel A, Patel, Raihaan, Thurston, Lindsey T, Lai, Meng-Chuan, Zucker, Kenneth J, Chakravarty, M Mallar, Lobaugh, Nancy J, and VanderLaan, Doug P
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T1 relaxometry ,brain tissue microstructure ,sexual orientation ,partial least squares ,adolescence ,brain development ,cortical surface area ,gender dysphoria ,cortical thickness ,10. No inequality ,structural MRI - Abstract
Gender dysphoria (GD) is characterized by distress due to an incongruence between experienced gender and sex assigned at birth. Sex-differentiated brain regions are hypothesized to reflect the experienced gender in GD and may play a role in sexual orientation development. Magnetic resonance brain images were acquired from 16 GD adolescents assigned female at birth (AFAB) not receiving hormone therapy, 17 cisgender girls, and 14 cisgender boys (ages 12-17 years) to examine three morphological and microstructural gray matter features in 76 brain regions: surface area (SA), cortical thickness (CT), and T1 relaxation time. Sexual orientation was represented by degree of androphilia-gynephilia and sexual attraction strength. Multivariate analyses found that cisgender boys had larger SA than cisgender girls and GD AFAB. Shorter T1, reflecting denser, macromolecule-rich tissue, correlated with older age and stronger gynephilia in cisgender boys and GD AFAB, and with stronger attractions in cisgender boys. Thus, cortical morphometry (mainly SA) was related to sex assigned at birth, but not experienced gender. Effects of experienced gender were found as similarities in correlation patterns in GD AFAB and cisgender boys in age and sexual orientation (mainly T1), indicating the need to consider developmental trajectories and sexual orientation in brain studies of GD.
81. Multivariate analysis of morphometric and quantitative magnetic resonance imaging metrics in aging and Alzheimer’s disease
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Bussy, Aurelie, primary, Patel, Raihaan, additional, Salaciak, Alyssa, additional, Farzin, Sarah, additional, Tullo, Stephanie, additional, Pelleieux, Sandra, additional, Villeneuve, Sylvia, additional, Poirier, Judes, additional, Breitner, John, additional, Devenyi, Gabriel, additional, Tardif, Christine, additional, and Chakravarty, M. Mallar, additional
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82. INTERPRETING DISEASE HETEROGENEITY IN ALZHEIMER’S AND PARKINSON’S DISEASE.
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Chakravarty, Mallar, Amaral, Robert S.C., Bhagwat, Nikhil, Patel, Raihaan, Garza-Villarreal, Eduardo, Devenyi, Gabriel, and Tae M Park, Min
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- 2016
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83. Characterizing Subcortical Structural Heterogeneity in Autism.
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MacDonald DN, Bedford SA, Olafson E, Park MTM, Devenyi GA, Tullo S, Patel R, Anagnostou E, Baron-Cohen S, Bullmore ET, Chura LR, Craig MC, Ecker C, Floris DL, Holt RJ, Lenroot R, Lerch JP, Lombardo MV, Murphy DGM, Raznahan A, Ruigrok ANV, Smith E, Shinohara RT, Spencer MD, Suckling J, Taylor MJ, Thurm A, Lai MC, and Chakravarty MM
- Abstract
Autism presents with significant phenotypic and neuroanatomical heterogeneity, and neuroimaging studies of the thalamus, globus pallidus and striatum in autism have produced inconsistent and contradictory results. These structures are critical mediators of functions known to be atypical in autism, including sensory gating and motor function. We examined both volumetric and fine-grained localized shape differences in autism using a large ( n =3145, 1045-1318 after strict quality control), cross-sectional dataset of T1-weighted structural MRI scans from 32 sites, including both males and females (assigned-at-birth). We investigated three potentially important sources of neuroanatomical heterogeneity: sex, age, and intelligence quotient (IQ), using a meta-analytic technique after strict quality control to minimize non-biological sources of variation. We observed no volumetric differences in the thalamus, globus pallidus, or striatum in autism. Rather, we identified a variety of localized shape differences in all three structures. Including age, but not sex or IQ, in the statistical model improved the fit for both the pallidum and striatum, but not for the thalamus. Age-centered shape analysis indicated a variety of age-dependent regional differences. Overall, our findings help confirm that the neurodevelopment of the striatum, globus pallidus and thalamus are atypical in autism, in a subtle location-dependent manner that is not reflected in overall structure volumes, and that is highly non-uniform across the lifespan., Competing Interests: Conflict of Interest EO is an employee of Genentech, Inc. DGMM has served on advisory Boards to Roche and Servier. He also receives a stipend for editorial work from Springer. M-CL serves as an editor of the journal Autism and has received editorial honorarium from SAGE Publications.
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- 2023
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84. Cerebellar and subcortical atrophy contribute to psychiatric symptoms in frontotemporal dementia.
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Bussy A, Levy JP, Best T, Patel R, Cupo L, Van Langenhove T, Nielsen JE, Pijnenburg Y, Waldö ML, Remes AM, Schroeter ML, Santana I, Pasquier F, Otto M, Danek A, Levin J, Le Ber I, Vandenberghe R, Synofzik M, Moreno F, de Mendonça A, Sanchez-Valle R, Laforce R, Langheinrich T, Gerhard A, Graff C, Butler CR, Sorbi S, Jiskoot L, Seelaar H, van Swieten JC, Finger E, Tartaglia MC, Masellis M, Tiraboschi P, Galimberti D, Borroni B, Rowe JB, Bocchetta M, Rohrer JD, Devenyi GA, Chakravarty MM, and Ducharme S
- Subjects
- Humans, C9orf72 Protein genetics, Magnetic Resonance Imaging, Cerebellum, Atrophy, Frontotemporal Dementia genetics
- Abstract
Recent studies have reported early cerebellar and subcortical impact in the disease progression of genetic frontotemporal dementia (FTD) due to microtubule-associated protein tau (MAPT), progranulin (GRN) and chromosome 9 open reading frame 72 (C9orf72). However, the cerebello-subcortical circuitry in FTD has been understudied despite its essential role in cognition and behaviors related to FTD symptomatology. The present study aims to investigate the association between cerebellar and subcortical atrophy, and neuropsychiatric symptoms across genetic mutations. Our study included 983 participants from the Genetic Frontotemporal dementia Initiative including mutation carriers and noncarrier first-degree relatives of known symptomatic carriers. Voxel-wise analysis of the thalamus, striatum, globus pallidus, amygdala, and the cerebellum was performed, and partial least squares analyses (PLS) were used to link morphometry and behavior. In presymptomatic C9orf72 expansion carriers, thalamic atrophy was found compared to noncarriers, suggesting the importance of this structure in FTD prodromes. PLS analyses demonstrated that the cerebello-subcortical circuitry is related to neuropsychiatric symptoms, with significant overlap in brain/behavior patterns, but also specificity for each genetic mutation group. The largest differences were in the cerebellar atrophy (larger extent in C9orf72 expansion group) and more prominent amygdalar volume reduction in the MAPT group. Brain scores in the C9orf72 expansion carriers and MAPT carriers demonstrated covariation patterns concordant with atrophy patterns detectable up to 20 years before expected symptom onset. Overall, these results demonstrated the important role of the subcortical structures in genetic FTD symptom expression, particularly the cerebellum in C9orf72 and the amygdala in MAPT carriers., (© 2023 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)
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- 2023
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85. Deep grey matter injury in multiple sclerosis: a NAIMS consensus statement.
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Ontaneda D, Raza PC, Mahajan KR, Arnold DL, Dwyer MG, Gauthier SA, Greve DN, Harrison DM, Henry RG, Li DKB, Mainero C, Moore W, Narayanan S, Oh J, Patel R, Pelletier D, Rauscher A, Rooney WD, Sicotte NL, Tam R, Reich DS, and Azevedo CJ
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- Humans, Brain pathology, Gray Matter pathology, Multiple Sclerosis pathology
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Although multiple sclerosis has traditionally been considered a white matter disease, extensive research documents the presence and importance of grey matter injury including cortical and deep regions. The deep grey matter exhibits a broad range of pathology and is uniquely suited to study the mechanisms and clinical relevance of tissue injury in multiple sclerosis using magnetic resonance techniques. Deep grey matter injury has been associated with clinical and cognitive disability. Recently, MRI characterization of deep grey matter properties, such as thalamic volume, have been tested as potential clinical trial end points associated with neurodegenerative aspects of multiple sclerosis. Given this emerging area of interest and its potential clinical trial relevance, the North American Imaging in Multiple Sclerosis (NAIMS) Cooperative held a workshop and reached consensus on imaging topics related to deep grey matter. Herein, we review current knowledge regarding deep grey matter injury in multiple sclerosis from an imaging perspective, including insights from histopathology, image acquisition and post-processing for deep grey matter. We discuss the clinical relevance of deep grey matter injury and specific regions of interest within the deep grey matter. We highlight unanswered questions and propose future directions, with the aim of focusing research priorities towards better methods, analysis, and interpretation of results., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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86. The relationship between subcortical brain volume and striatal dopamine D 2/3 receptor availability in healthy humans assessed with [ 11 C]-raclopride and [ 11 C]-(+)-PHNO PET.
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Caravaggio F, Ku Chung J, Plitman E, Boileau I, Gerretsen P, Kim J, Iwata Y, Patel R, Chakravarty MM, Remington G, and Graff-Guerrero A
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- Adult, Corpus Striatum anatomy & histology, Corpus Striatum diagnostic imaging, Female, Hippocampus anatomy & histology, Humans, Magnetic Resonance Imaging, Male, Organ Size, Oxazines, Positron-Emission Tomography, Raclopride, Radiopharmaceuticals, Thalamus anatomy & histology, Corpus Striatum metabolism, Hippocampus diagnostic imaging, Receptors, Dopamine D2 metabolism, Receptors, Dopamine D3 metabolism, Thalamus diagnostic imaging
- Abstract
Background: Abnormalities in dopamine (DA) and brain morphology are observed in several neuropsychiatric disorders. However, it is not fully understood how these abnormalities may relate to one another. For such in vivo findings to be used as biomarkers for neuropsychiatric disease, it must be understood how variability in DA relates to brain structure under healthy conditions. We explored how the availability of striatal DA D
2/3 receptors (D2/3 R) is related to the volume of subcortical brain structures in a sample of healthy humans. Differences in D2/3 R availability measured with an antagonist radiotracer ([11 C]-raclopride) versus an agonist radiotracer ([11 C]-(+)-PHNO) were examined., Methods: Data from 62 subjects scanned with [11 C]-raclopride (mean age = 38.98 ± 14.45; 23 female) and 68 subjects scanned with [11 C]-(+)-PHNO (mean age = 38.54 ± 14.59; 25 female) were used. Subcortical volumes were extracted from T1-weighted images using the Multiple Automatically Generated Templates (MAGeT-Brain) algorithm. Partial correlations were used controlling for age, gender, and total brain volume., Results: For [11 C]-(+)-PHNO, ventral caudate volumes were positively correlated with BPND in the dorsal caudate and globus pallidus (GP). Ventral striatum (VS) volumes were positively correlated with BPND in the VS. With [11 C]-raclopride, BPND in the VS was negatively correlated with subiculum volume of the hippocampus. Moreover, BPND in the GP was negatively correlated with the volume of the lateral posterior nucleus of the thalamus., Conclusion: Findings are purely exploratory and presented corrected and uncorrected for multiple comparisons. We hope they will help inform the interpretation of future PET studies where concurrent changes in D2/3 R and brain morphology are observed. Hum Brain Mapp 38:5519-5534, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)- Published
- 2017
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87. Hippocampal and Clinical Trajectories of Mild Cognitive Impairment with Suspected Non-Alzheimer's Disease Pathology.
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Chung JK, Plitman E, Nakajima S, Caravaggio F, Iwata Y, Gerretsen P, Kim J, Takeuchi H, Shinagawa S, Patel R, Chakravarty MM, and Graff-Guerrero A
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- Activities of Daily Living, Aged, Alzheimer Disease genetics, Alzheimer Disease metabolism, Amyloid metabolism, Apolipoprotein E4 genetics, Biomarkers cerebrospinal fluid, Cognition, Cognitive Dysfunction genetics, Cognitive Dysfunction metabolism, Disease Progression, Female, Follow-Up Studies, Hippocampus metabolism, Humans, Longitudinal Studies, Magnetic Resonance Imaging, Male, Organ Size, Positron-Emission Tomography, Alzheimer Disease diagnostic imaging, Cognitive Dysfunction diagnostic imaging, Hippocampus diagnostic imaging
- Abstract
Suspected non-Alzheimer's disease pathology (SNAP) characterizes individuals showing neurodegeneration (e.g., hypometabolism) without amyloid-β (Aβ). Findings from previous studies regarding clinical and structural trajectories of SNAP are inconsistent. Using data from the Alzheimer's Disease Neuroimaging Initiative, patients with amnestic mild cognitive impairment (MCI) were categorized into four groups: amyloid positive with hypometabolism (Aβ+ND+), amyloid only (Aβ+ND-), neither amyloid nor hypometabolism (Aβ-ND-), and SNAP (Aβ-ND+). Aβ+ND+(n = 33), Aβ+ND-(n = 32), and Aβ-ND-(n = 36) were matched to SNAP for age, gender, apolipoprotein E4 (apoE4) genotype, and scores on the Montreal Cognitive Assessment. Elderly controls (n = 40) were also matched to SNAP for age, gender, and apoE4 genotype. Longitudinal changes were compared across groups in terms of hippocampal volume, clinical symptoms, daily functioning, and cognitive functioning over a 2-year period. At baseline, no difference in cognition and functioning was observed between SNAP and Aβ+groups. SNAP showed worse clinical symptoms and impaired functioning at baseline compared to Aβ-ND-and controls. Two years of follow-up showed no differences in hippocampal volume changes between SNAP and any of the comparison groups. SNAP showed worse functional deterioration in comparison to Aβ-ND-and controls. However, Aβ+ND+ showed more severe changes in clinical symptoms in comparison to SNAP. Thus, patients with MCI and SNAP showed 1) more severe functional deterioration compared to Aβ-ND-and controls, 2) no differences with Aβ+ND-, and 3) less cognitive deterioration than Aβ+ND+. Future studies should investigate what causes SNAP, which is different from typical AD pathology and biomarker cascades.
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- 2017
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88. Depressive Symptoms and Small Hippocampal Volume Accelerate the Progression to Dementia from Mild Cognitive Impairment.
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Chung JK, Plitman E, Nakajima S, Chakravarty MM, Caravaggio F, Takeuchi H, Gerretsen P, Iwata Y, Patel R, Mulsant BH, and Graff-Guerrero A
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- Aged, Aged, 80 and over, Dementia pathology, Disease Progression, Female, Humans, Image Processing, Computer-Assisted, Longitudinal Studies, Magnetic Resonance Imaging, Male, Middle Aged, Psychiatric Status Rating Scales, Cognitive Dysfunction complications, Cognitive Dysfunction pathology, Depression etiology, Hippocampus pathology
- Abstract
Previous studies have highlighted that decreased hippocampal volume, an early neural correlate of dementia, is commonly observed in patients with mild cognitive impairment (MCI). However, it is unclear whether neurodegenerative and resultant clinical trajectories are accelerated in MCI patients with concomitant depressive symptoms, leading to a faster conversion to dementia stages than those who are not depressed. No longitudinal study has investigated whether depressed amnestic MCI (DEP+aMCI) patients show an earlier onset of progression to dementia than non-depressed amnestic MCI (DEP-aMCI) patients and whether progressive hippocampal volume reductions are related in the conversion process. Using data from Alzheimer's Disease Neuroimaging Initiative, we examined 2-year follow-up data from 38 DEP+aMCI patients and 38 matched DEP-aMCI patients and compared their ages of conversion from aMCI to AD and trajectories of progressive hippocampal volume changes. DEP+ and DEP- patients were defined as having baseline Geriatric Depression Scale scores of 5 or above and 0, respectively. DEP+ converters showed earlier ages of conversion to dementia (p = 0.009) and greater left hippocampal volume loss than both DEP- converters and DEP+ non-converters over the 2-year period (p = 0.003, p = 0.001, respectively). These findings could not be explained by changes in total brain volume, differences in their clinical symptoms of dementia, daily functioning, or apolipoprotein E4 genotypes. No difference in conversion rate to dementia or progressive hippocampal volume change was found between DEP+ patients and DEP-patients, which suggested depressive symptoms themselves may not lead to progression of dementia from MCI. In conclusion, there is a synergistic effect of depressive symptoms and smaller left hippocampal volume in MCI patients that accelerates conversion to dementia.
- Published
- 2016
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