A5007518409- Advanced MRI Techniques and Applications
- MRI in cancer diagnosis
- Radiomics and Machine Learning in Medical Imaging
- Advanced Neuroimaging Techniques and Applications
- Advanced NMR Techniques and Applications
- Lanthanide and Transition Metal Complexes
- Renal cell carcinoma treatment
- Cerebrovascular and Carotid Artery Diseases
- Breast Cancer Treatment Studies
- AI in cancer detection
- Electron Spin Resonance Studies
- Cardiovascular Health and Disease Prevention
- Cardiac Imaging and Diagnostics
- Glioma Diagnosis and Treatment
- Functional Brain Connectivity Studies
- Mitochondrial Function and Pathology
- Renal and Vascular Pathologies
- Metabolomics and Mass Spectrometry Studies
- Acute Ischemic Stroke Management
- Atomic and Subatomic Physics Research
- Prostate Cancer Diagnosis and Treatment
- RNA regulation and disease
- Diabetes Treatment and Management
- Diabetes Management and Research
- Chronic Kidney Disease and Diabetes
The University of Texas Southwestern Medical Center
2012-2025
Southwestern Medical Center
2020-2023
VA North Texas Health Care System
2016
Advanced Imaging Research (United States)
2012-2014
Purpose Proton magnetic resonance spectroscopy (MRS) of the brain can detect 2-hydroxyglutarate (2HG), oncometabolite produced in neoplasms harboring a mutation gene coding for isocitrate dehydrogenase ( IDH). We conducted prospective longitudinal imaging study to determine whether quantitative assessment 2HG by MRS could serve as noninvasive clinical biomarker IDH-mutated gliomas. Patients and Methods was performed 136 patients using point-resolved at 3 T parallel with standard assessment....
2‐Hydroxyglutarate (2HG) is produced in gliomas with mutations of isocitrate dehydrogenase (IDH) 1 and 2. The H resonances the J ‐coupled spins 2HG are extensively overlapped signals from other metabolites. Here, we report a comparative study at 3 T utility point‐resolved spectroscopy sequence standard short TE (35 ms) long (97 ms), which had been theoretically designed for detection 2.25‐ppm resonance. performance methods evaluated using data phantoms, seven healthy volunteers 22 subjects...
Purpose To evaluate the relationship between pulse wave velocity (PWV) from aortic arch and subsequent cerebral microvascular disease independent of other baseline cardiovascular risk factors among participants in multiethnic Dallas Heart Study. Materials Methods Each subject gave written consent to participate this HIPAA-compliant, institutional review board–approved prospective study. Aortic PWV was measured with phase-contrast magnetic resonance (MR) imaging a population sample (n = 1270)...
The natural history of white matter hyperintensity (WMH) progression resulting from normal aging versus comorbid vascular insults remains unclear. Therefore we investigated age-related differences in WMH volumes among a group with hypertension, abnormal body mass index, and diabetes mellitus to drawn the same population lacking any these comorbidities.WMH were acquired using 3T MRI for 2011 Dallas Heart Study participants. slope age regression was compared between comorbidity groups<50 ≥50...
The mechanisms of action incretin mimetics in patients with long-standing type 2 diabetes (T2D) and high insulin requirements have not been studied.To evaluate changes β-cell function, glucagon secretion, fat distribution after addition liraglutide to high-dose insulin.A single-center, randomized, double-blind, placebo-controlled trial.University Texas Southwestern Parkland Memorial Hospital clinics.Seventy-one (median, 17 years) T2D requiring treatment (>1.5 U/kg/d; average, 2.2 ± 0.9...
Asymmetry of the hippocampus is regarded as an important clinical finding, but limited data on hippocampal asymmetry are available for general population. Here we present from Dallas Heart Study determined by automated methods and its relationship to age, sex, ethnicity.3D magnetization-prepared rapid acquisition gradient echo MR imaging was performed in 2082 DHS-2 participants. The images were analyzed using 2 standard brain-segmentation programs, FSL-FIRST FreeSurfer. Individuals with...
On-premises artificial intelligence was accurate in ruling out obstructive coronary artery disease at CT angiography and achieved substantial to near-perfect agreement with human experts based on Coronary Artery Disease Reporting Data System 2.0 categories for stenosis severity plaque burden.
The (1)H resonances of γ-aminobutyric acid (GABA) in the human brain vivo are extensively overlapped with neighboring abundant other metabolites and remain indiscernible short-TE MRS at 7 T. Here we report that GABA resonance 2.28 ppm can be fully resolved by means echo time optimization a point-resolved spectroscopy (PRESS) scheme. Following numerical simulations phantom validation, subecho times PRESS were optimized (TE, TE2) = (31, 61) ms for detection GABA, glutamate (Glu), glutamine...
Purpose To compare the effectiveness of prospective, retrospective, and combined (prospective + retrospective) EPI distortion correction methods in bilateral breast diffusion‐weighted imaging (DWI) scans. Methods Five healthy female subjects underwent an axial DWI exam with without prospective B 0 inhomogeneity using slice‐by‐slice linear shimming. In each case, additional b=0 scan was performed polarity phase‐encoding gradient reversed, to generate estimated map; this map or a separately...
Understanding the relationships between age-related changes in brain structure and cognitive function has been limited by inconsistent methods for assessing imaging, small sample sizes, racially/ethnically homogeneous cohorts with biased selection based on risk factors. These limitations have prevented generalizability of results from morphology studies.To determine association 3.0-T structural magnetic resonance (MR) imaging measurements multiracial/multiethnic, population-based Dallas...
Purpose To develop a custom deep convolutional neural network (CNN) for noninvasive prediction of breast cancer nodal metastasis. Materials and Methods This retrospective study included patients with newly diagnosed primary invasive known pathologic (pN) clinical (cN) status who underwent dynamic contrast-enhanced (DCE) MRI at the authors' institution between July 2013 2016. Clinicopathologic data (age, estrogen receptor human epidermal growth factor 2 status, Ki-67 index, tumor grade) cN pN...
Objective: Breast cancer clinical stage and nodal status are the most clinically significant drivers of patient management, in combination with other pathological biomarkers, such as estrogen receptor (ER), progesterone or human epidermal growth factor 2 (HER2) tumor grade.Accurate prediction parameters can help avoid unnecessary intervention, including surgery.The objective was to investigate role magnetic resonance imaging (MRI) radiomics for yielding virtual prognostic biomarkers (ER,...
To develop and validate an algorithm to automatically quantify white matter hyperintensity (WMH) volume.Images acquired as part of the Dallas Heart Study, a multiethnic, population-based study cardiovascular health, were used algorithm. 3D magnetization prepared rapid acquisition gradient echo (MP-RAGE) 2D fluid-attenuated inversion recovery (FLAIR) images from 2082 participants. Images 161 participants (7.7% cohort) set intensity threshold maximize agreement between qualitative rating made...
Abstract The concentration of glycine (Gly) was measured in gray matter (GM) and white (WM) the human brain using single‐voxel localized 1 H MRS at 7 T. A point‐resolved spectroscopy sequence with echo time = 150 ms used for measuring Gly levels various regions frontal occipital lobes 11 healthy volunteers one subject a glioblastoma. spectra were analyzed LCModel basis functions generated from density matrix simulations that included effects volume radio‐frequency gradient pulses. fraction...
Purpose To generate a preclinical model of isocitrate dehydrogenase (IDH) mutant gliomas from glioma patients and design MRS method to test the compatibility 2‐hydroxyglutarate (2HG) production between patients. Methods Five patient‐derived xenograft (PDX) mice were generated two with IDH1 R132H mutation. A PRESS sequence was tailored at 9.4 T, computer simulation phantom analyses, for improving 2HG detection in mice. other metabolites PDX measured using optimized T compared 3 measurements...
Background Diffusion‐weighted imaging (DWI) is commonly used to detect prostate cancer, and a major clinical challenge differentiating aggressive from indolent disease. Purpose To compare 14 site‐specific parametric fitting implementations applied the same dataset of whole‐mount pathologically validated DWI test hypothesis that cancer differentiation varies with different algorithms. Study Type Prospective. Population Thirty‐three patients prospectively imaged prior prostatectomy. Field...
Despite the recent advances of deep learning algorithms in medical imaging, automatic segmentation for kidneys Magnetic Resonance Imaging (MRI) examinations are lacking. Automated MRI can enable several clinical applications and use radiomics machine analysis renal disease. In this work, we propose application a Mask R-CNN coronal T2- weighted single-shot fast spin echo MRI. We morphological operations as post-processing to further improve performance task. With 5-fold cross-validation data,...
<h3>BACKGROUND AND PURPOSE:</h3> Age-related white matter hyperintensities have prognostic implications, but no accepted clinical standard exists for their assessment. We propose a simple objective visual rating system by using 3T brain MR imaging. <h3>MATERIALS METHODS:</h3> imaging from 559 participants was processed an automated method to determine WMH volumes and evaluated with new scale based on the single largest lesion diameter regardless of location. The reproducibility assessed....
Purpose To test whether citrate is elevated in adult patients with gliomas using 1 H magnetic resonance spectroscopy (MRS) at 3T vivo. Methods Thirty‐four were enrolled the study, including six subjects glioblastomas, eight astrocytomas (World Health Organization grade 3, n = 5; 2, 3), and 20 oligodendrogliomas (grade 15). Five healthy volunteers studied for baseline data. Single‐voxel localized spectra collected point‐resolved (PRESS) echo times of 35 97 ms analyzed LCModel software...
Glioblastoma (GBM), the most common primary brain tumor, is resistant to currently available treatments. The development of mouse models human GBM has provided a tool for studying mechanisms involved in tumor initiation and growth as well platform preclinical investigation new drugs. In this study we used 1 H MR spectroscopy neurochemical profile orthotopic (HOT) model GBM. goal was evaluate differences metabolite concentrations HOT mice when compared with normal order determine if MRS could...
Elevated urinary albumin to creatinine ratio (ACR) and white matter hyperintensity (WMH) volume seen on brain MRI are measures of microvascular disease which may have shared susceptibility metabolic vascular insults. We hypothesized that elevated ACR be useful as inexpensive biomarker predict presence cerebral disease. assessed the association between at study entry subsequent WMH volume. evaluated pulse pressure, mean arterial hypertension duration, waist circumference, fasting glucose,...
Abstract Purpose To develop a portable MR perfusion phantom for quality‐controlled assessment and reproducibility of arterial spin labeled (ASL) measurement. Methods A 3D‐printed was developed that mimics the branching vessels, capillaries, chamber containing cellulose sponge representing tissue characteristics. peristaltic pump circulated distilled water through phantom, first evaluated at 300, 400, 500 mL/min. Longitudinal performed using 2D pseudo‐continuous ASL 20 post‐label delays...
Deep learning has been successful in predicting tumor malignancy. Clear cell renal carcinoma (ccRCC) diagnosis may help decision making between active surveillance and definitive intervention. In this study, we investigate the effects of different factors on performance deep classification ccRCC using T2w images. We demonstrate that 15 CNN models varied substantially. The choice models, cropped image size, type inputs greatly altered classification. achieved best AUC value 0.81, which is...