A5016425568- Advanced MRI Techniques and Applications
- Electrical and Bioimpedance Tomography
- Functional Brain Connectivity Studies
- Advanced NMR Techniques and Applications
- Neuroscience and Neuropharmacology Research
- Advanced Neuroimaging Techniques and Applications
- Epilepsy research and treatment
- Atomic and Subatomic Physics Research
- Neural dynamics and brain function
- Neuroscience and Neural Engineering
- Glioma Diagnosis and Treatment
- Nanoparticle-Based Drug Delivery
- NMR spectroscopy and applications
- Nanoplatforms for cancer theranostics
- EEG and Brain-Computer Interfaces
- Neonatal and fetal brain pathology
- Characterization and Applications of Magnetic Nanoparticles
- Drug Transport and Resistance Mechanisms
- Optical Imaging and Spectroscopy Techniques
- Traditional Chinese Medicine Studies
- Infrared Thermography in Medicine
- Electrostatics and Colloid Interactions
- Neurological disorders and treatments
- Fetal and Pediatric Neurological Disorders
- Nuclear Physics and Applications
University of California, Los Angeles
2006-2022
University of California System
2012
University of New Mexico
2000-2010
Brain Mapping Foundation
2006
Huntington Medical Research Institutes
2001-2002
Good Samaritan Hospital
2000
Object. Magnetoencephalography (MEG) and magnetic source (MS) imaging are techniques that have been increasingly used for preoperative localization of epileptic foci areas eloquent cortex. The use MEG examinations must be carefully balanced against the high cost technological investments required to perform these studies, particularly when less expensive alternative methods available. To help elucidate value MEG, authors critically reviewed their experience with whole-head in case management...
We recently demonstrated that ultra-high-speed real-time fMRI using multi-slab echo-volumar imaging (MEVI) significantly increases sensitivity for mapping task-related activation and resting state networks (RSNs) compared to echo-planar (Posse et al. 2012). In the present study we characterize of MEVI RSN connectivity dynamics, comparing independent component analysis (ICA) a novel seed-based (SBCA) combines sliding-window correlation with meta-statistics. This SBCA approach is shown...
The development of nonradioactive and targeted magnetonanoparticles (MNP) capable crossing the blood-brain barrier (BBB) concentrating in epileptogenic tissues acute chronic animal models temporal lobe epilepsy to render these visible on magnetic resonance imaging (MRI).Nonradioactive alpha methyl tryptophan (AMT) was covalently attached MNP composed iron oxide dextran. A rodent model prepared by injecting kainic acid into right hippocampus. AMT-MNP or plain injected tail-vein two animals...
Source localization models assume brain electrical conductivities are isotropic at about 0.33 S/m. These assumptions have not been confirmed ex vivo in humans. This study determined bidirectional from pediatric epilepsy surgery patients. Electrical perpendicular and parallel to the pial surface of neocortex subcortical white matter (n = 15) were measured using 4-electrode technique compared with clinical variables. Mean (+/-SD) 0.10 +/- 0.01 S/m, varied by 243% patient patient. Perpendicular...
The electrical conductivities of freshly excised brain tissues from 24 patients were measured. diffusion-MRI the hydrogen nuclei water molecules regions that subsequently was also Analysis these measurements indicates differences between samples' are primarily due to their densities solvated sodium cations. Concomitantly, sample-to-sample variations diffusion constants relatively small. This finding suggests non-invasive in-vivo tissues' local sodium-cation density can be utilized estimate...
We have developed a new analytical method that uses nuclear magnetic resonance (NMR) imaging data to quantify lung water content and distribution. This generates distribution of density in which the fraction voxels corresponding given is plotted on vertical axis as function horizontal axis, thereby complementing spatial information provided by NMR image. obtained reproducible at comparable volumes normal excised lungs intact living rats. In unperfused rat lungs, varied with degree inflation,...
Abstract A new method for enhancing MRI contrast between gray matter (GM) and white (WM) in epilepsy surgery patients with symptomatic lesions is presented. This uses the radiation damping feedback interaction high‐field to amplify due small differences resonance frequency GM WM corresponding variations tissue susceptibility. High‐resolution damping‐enhanced (RD) images of vitro brain from five were acquired at 14 T compared conventional 1 ‐, proton density (PD)‐weighted images. The RD...
We analyze the transient-dc and frequency-dependent electrical conductivities between blocking electrodes. extend this analysis to measurements of ions’ transport in freshly excised bulk samples human brain tissue whose complex cellular structure produces blockages. The associated ionic charge-carrier density diffusivity are consistent with local values for sodium cations determined non-invasively by MRI (NMR) diffusion-MRI (spin-echo NMR). characteristic separation blockages, about 450...
The purpose of this brief communication is to describe two novel imaging approaches the study epilepsy, being undertaken at UCLA Seizure Disorder Center. One involves structural anatomic surface modeling utilizing statistical parametric mapping (SPM) identify epilepsy-related magnetic resonance (MRI) abnormalities hippocampus and neocortex. other utilizes functionalized magnetonanoparticles (MNPs) conjugated bioactive ligands in order image specific local cerebral function using MRI, rather...
We study the effect of lesions on our four-electrode measurements ionic conductivity (1 cm3) samples human brain excised from patients undergoing pediatric epilepsy surgery. For most (about 94 %) low-frequency rises upon increasing applied frequency. attributed this behavior to long-range (0.4 mm) diffusion solvated sodium cations before encountering impenetrable blockages such as cell membranes, blood vessels and walls. By contrast, some (6 tissue falls with attribute unusual...
Transient and frequency-dependent conductivity measurements on excised brain-tissue lesions from epilepsy patients indicate that sodium cations are the predominant charge carriers. The transient ultimately vanishes as ions encounter blockages. initial final values of correspond to high-frequency low-frequency limits conductivity, respectively. Carrier dynamics determines between these limits. Typically, rises monotonically with increasing frequency. By contrast, when pathology examinations...
Epileptogenic lesions have higher concentrations of sodium than does normal brain tissue. Such are palpably recognized by a surgeon and then excised in order to eliminate epileptic seizures with their associated abnormal electrical behavior. Here, we study the frequency-dependent conductivities lesion-laden tissues from brains epilepsy patients. The low-frequency (<1000 Hz) conductivity biological tissue primarily probes extracellular solvated sodium-cations traveling parallel membranes...