Julio E. Villalón‐Reina
A5070275145- Advanced Neuroimaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Functional Brain Connectivity Studies
- MRI in cancer diagnosis
- Fetal and Pediatric Neurological Disorders
- Congenital heart defects research
- Coronary Artery Anomalies
- Bone and Joint Diseases
- Traumatic Brain Injury Research
- Alzheimer's disease research and treatments
- Brain Tumor Detection and Classification
- Traumatic Brain Injury and Neurovascular Disturbances
- Congenital Heart Disease Studies
- Dementia and Cognitive Impairment Research
- Genetics and Neurodevelopmental Disorders
- Parkinson's Disease Mechanisms and Treatments
- NMR spectroscopy and applications
- Radiomics and Machine Learning in Medical Imaging
- Tensor decomposition and applications
- Neurological disorders and treatments
- Genetic Associations and Epidemiology
- Otolaryngology and Infectious Diseases
- Neural dynamics and brain function
- Health, Environment, Cognitive Aging
- Genomic variations and chromosomal abnormalities
Imaging Center
2013-2025
Southern California University for Professional Studies
2013-2025
University of Southern California
2016-2025
University of California, Los Angeles
2013-2021
Illinois Institute of Technology
2020
SUNY Upstate Medical University
2019
Marina Del Rey Hospital
2018
Fuller Theological Seminary
2017
LAC+USC Medical Center
2017
UCLA Medical Center
2017
Abstract Tractography based on non-invasive diffusion imaging is central to the study of human brain connectivity. To date, approach has not been systematically validated in ground truth studies. Based a simulated data set with tracts, we organized an open international tractography challenge, which resulted 96 distinct submissions from 20 research groups. Here, report encouraging finding that most state-of-the-art algorithms produce tractograms containing 90% bundles (to at least some...
The Alzheimer's Disease Neuroimaging Initiative (ADNI) recently added diffusion tensor imaging (DTI), among several other new modalities, in an effort to identify sensitive biomarkers of disease (AD). While anatomical MRI is the main structural neuroimaging method used most AD studies and clinical trials, DTI microscopic white matter (WM) changes not detectable with standard MRI, offering additional markers neurodegeneration. Prior report lower fractional anisotropy (FA), increased mean,...
Abstract The 22q11.2 deletion (22q11DS) is a common chromosomal microdeletion and potent risk factor for psychotic illness. Prior studies reported widespread cortical changes in 22q11DS, but were generally underpowered to characterize neuroanatomic abnormalities associated with psychosis and/or effects of variability size. To address these issues, we developed the ENIGMA (Enhancing Neuro Imaging Genetics Through Meta-Analysis) Working Group, representing largest analysis brain structural...
Abstract The ENIGMA‐DTI (diffusion tensor imaging) workgroup supports analyses that examine the effects of psychiatric, neurological, and developmental disorders on white matter pathways human brain, as well normal variation its genetic associations. seven ENIGMA disorder‐oriented working groups used workflow to derive patterns deficits using coherent coordinated model disease across cohorts worldwide. This yielded largest studies detailing in schizophrenia spectrum disorder (SSD), bipolar...
Objective: 22q11.2 deletion syndrome (22q11DS) is among the strongest known genetic risk factors for schizophrenia. Previous studies have reported variable alterations in subcortical brain structures 22q11DS. To better characterize 22q11DS, including modulating effects of clinical and heterogeneity, authors studied a large multicenter neuroimaging cohort from ENIGMA Deletion Syndrome Working Group. Methods: Subcortical were measured using harmonized protocols gross volume shape morphometry...
A comprehensive characterization of the brain's white matter is critical for improving our understanding healthy and diseased aging. Here we used diffusion-weighted magnetic resonance imaging (dMRI) to estimate age sex effects on microstructure in a cross-sectional sample 15,628 adults aged 45-80 years old (47.6% male, 52.4% female). Microstructure was assessed using following four models: conventional single-shell model, diffusion tensor (DTI); more advanced distribution function (TDF); an...
Abstract Age-related white matter (WM) microstructure maturation and decline occur throughout the human lifespan, complementing process of gray development degeneration. Here, we create normative lifespan reference curves for global regional WM by harmonizing diffusion MRI (dMRI)-derived data from ten public datasets (N = 40,898 subjects; age: 3–95 years; 47.6% male). We tested three harmonization methods on tensor imaging (DTI) based fractional anisotropy (FA), a metric microstructure,...
Traumatic brain injury (TBI) is the leading cause of death and disability in children can lead to a wide range impairments. Brain imaging methods such as DTI (diffusion tensor imaging) are uniquely sensitive white matter (WM) damage that common TBI. However, higher-level analyses using tractography complicated by decreased FA (fractional anisotropy) characteristic TBI, which result premature tract endings. We used newly developed autoMATE (automated multi-atlas extraction) method identify...
Abstract 22q11.2 deletion syndrome (22q11DS)—a neurodevelopmental condition caused by a hemizygous on chromosome 22—is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples variable methods led to contradictory results. Here we present the largest study ever conducted dMRI-derived measures WM 22q11DS (334...
Abstract Fiber tractography based on non-invasive diffusion imaging is at the heart of connectivity studies human brain. To date, approach has not been systematically validated in ground truth studies. Based a simulated brain dataset with white matter tracts, we organized an open international challenge, which resulted 96 distinct submissions from 20 research groups. While most state-of-the-art algorithms reconstructed 90% bundles to least some extent, average they produced four times more...
Age-related white matter (WM) microstructure maturation and decline occur throughout the human lifespan with a unique trajectory in brain, complementing process of gray development degeneration. Normative modeling can establish reference curves for typical WM microstructural aging patterns by pooling data from many independent studies that span different age ranges. Here, we create such harmonizing diffusion MRI (dMRI)-derived ten public datasets (N = 40,898 subjects; age: 3-95 years; 47.6%...
22q11.2 Microdeletion Syndrome (22q11DS) is a highly penetrant genetic mutation associated with significantly increased risk for psychosis. Aberrant neurodevelopment may lead to inappropriate neural circuit formation and cerebral dysconnectivity in 22q11DS, which contribute symptom development. Here we examined: (1) differences between 22q11DS participants typically developing controls diffusion tensor imaging (DTI) measures within white matter tracts; (2) whether there an altered...
The progression of Parkinson's disease (PD) is associated with microstructural alterations in neural pathways, contributing to both motor and cognitive decline. However, conflicting findings have emerged due the use heterogeneous methods small studies. Here we performed a large diffusion MRI study PD, integrating data from 17 cohorts worldwide, identify stage-specific profiles white matter differences. Diffusion-weighted 1654 participants diagnosed PD (age: 20–89 years; 33% female) 885...
Introduction: Diffusion MRI is sensitive to the microstructural properties of brain tissues and shows great promise in detecting effects degenerative diseases. However, many approaches analyze single measures averaged over regions interest, without considering underlying fiber geometry. Methods: Here, we propose a novel Macrostructure-Informed Normative Tractometry (MINT) framework, investigate how white matter microstructure macrostructure are jointly altered mild cognitive impairment (MCI)...
22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It associated with a significant impact on brain structure, including prominent reductions gray matter volume (GMV), and neuropsychiatric manifestations, cognitive impairment psychosis. unclear whether GMV alterations 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 22q11DS: 51% females, mean age [SD] 18.2 [9.2]; 313 typically developing [TD] controls: 46% 18.0...
Purpose In diffusion MRI (dMRI), fractional anisotropy derived from the single‐tensor model (FA DTI ) is most widely used metric to characterize white matter (WM) microarchitecture, despite known limitations in regions with crossing fibers. Due time constraints when scanning patients clinical settings, high angular resolution imaging acquisition protocols, often overcome these limitations, are still rare population studies. However, tensor distribution function (TDF) may be multiple...
Traumatic brain injury (TBI) can cause widespread and prolonged degeneration. TBI affect cognitive function integrity for many years after injury, often with lasting effects in children, whose brains are still immature. Although varies how it affects different individuals, image analysis methods such as tensor-based morphometry (TBM) reveal common areas of atrophy on magnetic resonance imaging (MRI), secondary the initial which will differ between subjects. Here we studied 36 pediatric...
To examine longitudinal trajectories of white matter organization in pediatric moderate/severe traumatic brain injury (msTBI) over a 12-month period.We studied 21 children (16 M/5 F) with msTBI, assessed 2-5 months postinjury and again 13-19 postinjury, as well 20 well-matched healthy control children. We corpus callosum function through interhemispheric transfer time (IHTT), measured using event-related potentials, related this to diffusion-weighted MRI measures (WM) microstructure. At the...
Diffusion tensor imaging (DTI) is a key neuroimaging modality for assessing brain tissue microstructure, yet high-quality acquisitions are costly, time-intensive, and prone to artifacts. To address data scarcity privacy concerns - augment the available training deep learning methods synthetic DTI generation has gained interest. Specifically, denoising diffusion probabilistic models (DDPMs) have emerged as promising approach due their superior fidelity, diversity, controllability, stability...
People differ in their cognitive functioning.This variability has been exhaustively examined at the behavioral, neural and genetic level to uncover mechanisms by which some individuals are more cognitively efficient than others.Studies investigating underpinnings of interindividual differences cognition aim establish a reliable nexus between functional/structural properties given brain network higher order performance.However, these studies have produced inconsistent results, might be partly...