A5091239458- Medical Imaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Radiomics and Machine Learning in Medical Imaging
- Cardiac Imaging and Diagnostics
- Functional Brain Connectivity Studies
- Cerebrovascular and Carotid Artery Diseases
- Advanced Radiotherapy Techniques
- Advanced X-ray and CT Imaging
- Atherosclerosis and Cardiovascular Diseases
- Cardiovascular Function and Risk Factors
- Attention Deficit Hyperactivity Disorder
- MRI in cancer diagnosis
- Radiation Therapy and Dosimetry
- Medical Imaging and Pathology Studies
- Radiopharmaceutical Chemistry and Applications
- Advanced Neuroimaging Techniques and Applications
- Cardiovascular Health and Disease Prevention
- Cardiac Valve Diseases and Treatments
- Glioma Diagnosis and Treatment
- Cardiovascular Disease and Adiposity
- Adipokines, Inflammation, and Metabolic Diseases
- Atrial Fibrillation Management and Outcomes
- Cardiac Structural Anomalies and Repair
- Multiple Sclerosis Research Studies
- Cancer, Lipids, and Metabolism
Massachusetts General Hospital
2016-2025
Harvard University
2016-2025
Athinoula A. Martinos Center for Biomedical Imaging
2016-2025
Harvard–MIT Division of Health Sciences and Technology
2021-2024
Universidad Carlos III de Madrid
2022-2024
Cognitive Neuroimaging Lab
2022
Massachusetts Institute of Technology
2014-2022
Boston University
2022
Clinical Research Institute
2016
University of Pennsylvania
2015
Although substantial evidence has established that microglia and astrocytes play a key role in the establishment maintenance of persistent pain animal models, glial cells human disorders remains unknown. Here, using novel technology integrated positron emission tomography-magnetic resonance imaging recently developed radioligand (11)C-PBR28, we show increased brain levels translocator protein (TSPO), marker activation, patients with chronic low back pain. As Ala147Thr polymorphism TSPO gene...
The study of patients with semantic dementia, a variant frontotemporal lobar degeneration, has emerged over the last two decades as an important lesion model for studying human memory. Although it is well-known that dementia associated temporal lobe controversy remains whether deficit due to diffuse damage, damage only sub-region or even less severe elsewhere in brain. manner which right and left lobes contribute knowledge also not fully elucidated. In this we used unbiased imaging analyses...
The Ingenuity TF PET–MRI is a newly released whole-body hybrid PET–MR imaging system with Philips time-of-flight GEMINI PET and Achieva 3T X-series MRI system. Compared to PET–CT, modifications the positron emission tomography (PET) gantry were made avoid mutual interference deliver uncompromising performance which equivalent standalone systems. was redesigned introduce magnetic shielding for photomultiplier tubes (PMTs). Stringent electromagnetic noise requirements of MR necessitated...
Accurate γ-photon attenuation correction (AC) is essential for quantitative PET/MRI as there no simple relation between MR image intensity and coefficients. Attenuation maps (μ-maps) can be derived by segmenting images assigning coefficients to the compartments. Ultrashort-echo-time (UTE) sequences have been used separate cortical bone air, Dixon technique has enabled differentiation soft adipose tissues. Unfortunately, sequential application of these time-consuming complicates registration....
To accurately quantify the radioactivity concentration measured by PET, emission data need to be corrected for photon attenuation; however, MRI signal cannot easily converted into attenuation values, making correction (AC) in PET/MRI challenging. In order further improve current vendor-implemented MR-AC methods absolute quantification, a number of prototype have been proposed literature. These can categorized three types: template/atlas-based, segmentation-based, and reconstruction-based....
Evidence from human post mortem, in vivo and animal model studies implicates the neuroimmune system activated microglia pathology of amyotrophic lateral sclerosis. The study aim was to further evaluate neuroinflammation individuals with sclerosis using [11C]-PBR28 positron emission tomography. Ten patients (seven males, three females, 38–68 years) ten age- binding affinity-matched healthy volunteers (six four 33–65 completed a tomography scan. Standardized uptake values were calculated 60 90...
We present an approach for head MR-based attenuation correction (AC) based on the Statistical Parametric Mapping 8 (SPM8) software, which combines segmentation- and atlas-based features to provide a robust technique generate maps (μ maps) from MR data in integrated PET/MR scanners.Coregistered anatomic CT images of 15 glioblastoma subjects were used templates. The these first segmented into 6 tissue classes (gray matter, white cerebrospinal fluid, bone, soft tissue, air), then nonrigidly...
In multiple sclerosis (MS), using simultaneous magnetic resonance-positron emission tomography (MR-PET) imaging with 11 C-PBR28, we quantified expression of the 18kDa translocator protein (TSPO), a marker activated microglia/macrophages, in cortex, cortical lesions, deep gray matter (GM), white (WM) and normal-appearing WM (NAWM) to investigate vivo pathological clinical relevance neuroinflammation.Fifteen secondary-progressive MS (SPMS) patients, 12 relapsing-remitting (RRMS) 14 matched...
Previous data suggest that methylphenidate can have variable effects on different cognitive tasks both within and between individuals. This is thought to be underpinned by inverted U-shaped relationships performance dopaminergic activity in relatively separate fronto-striatal circuits reflected individual differences trait impulsivity. Direct evidence for this currently lacking. In study, we demonstrate the first time therapeutic doses of oral administered young healthy subjects result sized...
Understanding the neural basis of consciousness is fundamental to neuroscience research. Disruptions in cortico-cortical connectivity have been suggested as a primary mechanism unconsciousness. By using novel combination positron emission tomography and functional magnetic resonance imaging, we studied anesthesia-induced unconsciousness recovery α2-agonist dexmedetomidine. During unconsciousness, cerebral metabolic rate glucose blood flow were preferentially decreased thalamus, Default Mode...
Whole-body attenuation correction (AC) is still challenging in combined PET/MR scanners. We describe Dixon-VIBE Deep Learning (DIVIDE), a deep-learning network that allows synthesizing pelvis pseudo-CT maps based only on the standard Dixon volumetric interpolated breath-hold examination (Dixon-VIBE) images currently acquired for AC some commercial <b>Methods:</b> propose between four 2-dimensional (2D) MR (water, fat, in-phase, and out-of-phase) their corresponding 2D CT image. In contrast...
Through the combined use of (18)F-fallypride positron emission tomography and magnetic resonance imaging this study examined neural mechanisms underlying attentional deficits associated with attention deficit/hyperactivity disorder their potential reversal a single therapeutic dose methylphenidate. Sixteen adult patients 16 matched healthy control subjects were scanned tested on computerized sustained task after oral methylphenidate (0.5 mg/kg) placebo administration in within-subject,...
To characterize [11 C]-PBR28 brain uptake using positron emission tomography (PET) in people with amyotrophic lateral sclerosis (ALS) and primary (PLS). We have previously shown increased the precentral gyrus a small group of ALS patients. Herein, we confirm our initial finding, study longitudinal changes, gray versus white matter distribution larger cohort patients PLS.Eighty-five participants including 53 ALS, 11 PLS, 21 healthy controls underwent integrated PET-magnetic resonance imaging....
Background and Purpose— Inflammation is a major risk factor for atherosclerotic plaque rupture clinical events. Previous studies have shown that [ 18 F]fluorodeoxyglucose (FDG) uptake correlates with macrophage content. In this study we examined the reproducibility of 3 methods quantifying FDG in carotid arteries using positron emission tomography (PET). The correlation between 2 simplified parameters (standardized value [SUV], vessel wall-to-blood ratio [VBR]) gold standard technique...
Hypoxia is an important microenvironmental factor influencing atherosclerosis progression by inducing foam-cell formation, metabolic adaptation of infiltrated macrophages, and plaque neovascularization. Therefore, imaging hypoxia could serve as a marker lesions at risk.Advanced aortic was induced in 18 rabbits atherogenic diet double balloon endothelial denudation. Animals underwent (18)F-fluoromisonidazole positron emission tomographic (18)F-fluorodeoxyglucose after 6 to 8 months...
In this cross-sectional study, we aimed to evaluate brain structural abnormalities in relation glial activation the same cohort of participants.Ten individuals with amyotrophic lateral sclerosis (ALS) and 10 matched healthy controls underwent imaging using integrated MR/PET radioligand [11C]-PBR28. Diagnosis history clinical assessments including Upper Motor Neuron Burden Scale (UMNB) were obtained from patients ALS. Diffusion tensor (DTI) analyses tract-based spatial statistics tractography...
Huntington's disease is a devastating neurodegenerative genetic disorder that causes progressive motor dysfunction, emotional disturbances, and cognitive impairment. Unfortunately, there no treatment to cure or slow the progression of disease. Neuroinflammation one hallmark disease, modulation neuroinflammation has been suggested as potential target for therapeutic intervention. The relationship between markers pathology still poorly understood. To improve our understanding in we measured...
Abstract Mechanisms of neuroimmune and mitochondrial dysfunction have been repeatedly implicated in autism spectrum disorder (ASD). To examine these mechanisms ASD individuals, we measured the vivo expression 18 kDa translocator protein (TSPO), an activated glial marker expressed on membranes. Participants underwent scanning a simultaneous magnetic resonance–positron emission tomography (MR–PET) scanner with second-generation TSPO radiotracer [ 11 C]PBR28. By comparing 15 young adult males...
Abstract The social motivation hypothesis of autism posits that spectrum disorder (ASD) is characterized by impaired to seek out experience early in life interferes with the development functioning. This framework suggests mesolimbic dopamine function underlies compromised responses rewards ASD. Although this supported functional magnetic resonance imaging (fMRI) studies, no molecular study has evaluated striatal functioning response Here, we examined during monetary incentive processing ASD...