A5017274918- Ultrasound and Hyperthermia Applications
- Photoacoustic and Ultrasonic Imaging
- Ultrasound Imaging and Elastography
- Ultrasound and Cavitation Phenomena
- Advanced MRI Techniques and Applications
- Nanoplatforms for cancer theranostics
- Advanced Radiotherapy Techniques
- Atomic and Subatomic Physics Research
- Angiogenesis and VEGF in Cancer
- Medical Imaging Techniques and Applications
- Functional Brain Connectivity Studies
- Optical Imaging and Spectroscopy Techniques
- Radiopharmaceutical Chemistry and Applications
- Neurological disorders and treatments
- Electronic Packaging and Soldering Technologies
- Infrared Thermography in Medicine
- Medical Image Segmentation Techniques
- Nanoparticle-Based Drug Delivery
- Peripheral Artery Disease Management
- Microfluidic and Bio-sensing Technologies
- Thermal Regulation in Medicine
- Neural dynamics and brain function
- Vagus Nerve Stimulation Research
- Cardiovascular and Diving-Related Complications
- Optical Coherence Tomography Applications
Vanderbilt University
2016-2025
Vanderbilt University Medical Center
2017-2025
University of Mississippi Medical Center
2022
University of North Carolina at Chapel Hill
2020-2022
North Carolina State University
2022
Korea Advanced Institute of Science and Technology
2022
Illinois Institute of Technology
2022
Tohoku University
2022
Shanghai Jiao Tong University
2022
Institute of Electrical and Electronics Engineers
2022
We present the first study of effects monolayer shell physicochemical properties on destruction lipid-coated microbubbles during insonification with single, one-cycle pulses at 2.25 MHz and low-duty cycles. Shell cohesiveness was changed by varying phospholipid emulsifier composition, microstructure controlled postproduction processing. Individual initial resting diameters between 1 10 /spl mu/m were isolated recorded pulsing brightfield fluorescence video microscopy. Microbubble occurred...
Many thousands of contrast ultrasound studies have been conducted in clinics around the world. In addition, microbubbles employed these examinations are being widely investigated to deliver drugs and genes. Here, for first time, oscillation small vessels is directly observed shown be substantially different than that predicted by previous models imaged within large fluid volumes. Using pulsed with a center frequency 1MHz peak rarefactional pressure 0.8 or 2.0MPa, microbubble expansion was...
Purpose: To characterize the effect of low-frequency contrast material–enhanced ultrasound on vascular endothelium and to determine parameters techniques required deliver a therapeutic agent by using chorioallantoic membrane (CAM) model. Materials Methods: All in vivo animal procedures were conducted with institutional Animal Care Use Committee approval. Extravasation 8.5-nm-diameter fluorescein isothiocyanate–labeled dextran was evaluated vasculature chick CAM Intravital microscopy...
Focused ultrasound (FUS) has gained recognition as a technique for non-invasive neuromodulation with high spatial precision and the ability to both excite inhibit neural activity. Here we demonstrate that MRI-guided FUS is capable of exciting precise targets within areas 3a/3b in monkey brain, causing downstream activations off-target somatosensory associated brain regions which are simultaneously detected by functional MRI. The similarity between natural tactile stimulation-and FUS- evoked...
Transcranial focused ultrasound (FUS) stimulation under MRI guidance, coupled with functional (fMRI) monitoring of effects, offers a precise, noninvasive technology to dissect brain circuits and modulate altered networks in neurological psychiatric disorders. Here we show that at moderate intensities modulated neural activity bi-directionally. Concurrent sonication somatosensory areas 3a/3b 250 kHz FUS suppressed the fMRI signals produced there by peripheral tactile stimulation, while same...
We report on a novel application of the layer-by-layer (LbL) assembly technique to attach multiple layers DNA and poly-l-lysine (PLL) onto preformed lipid-coated microbubbles increase loading capacity. first measured effects cationic lipid fraction salt concentration microbubble stability. Microbubble production stability were robust up 40 mol % in 10 mM NaCl. adsorption was heterogeneous over shell occurred primarily condensed phase domains. The amount adsorbed DNA, subsequently PLL,...
Abstract Ultrasound is gaining traction as a neuromodulation method due to its ability remotely and non-invasively modulate neuronal activity with millimeter precision. However, there little consensus about optimal ultrasound parameters required elicit how specific drive mechanisms that underlie neuromodulation. We address these questions in this work by performing study determine effective transgenic mouse brain slice model enables calcium imaging quantitative readout of for report (1)...
Transcranial ultrasonic stimulation (TUS) is an emerging technology for non-invasive brain stimulation. Currently, there are no established guidelines the safe application of neuromodulation in humans beyond those used diagnostic ultrasound. Therefore, a series meetings, International Consortium Ultrasonic Stimulation Safety and Standards (ITRUSST) has expert consensus on considerations biophysical safety TUS. As with ultrasound, two main risks associated TUS: mechanical thermal bioeffects....
Low-power multipulse contrast ultrasound imaging provides a promising tool to quantify angiogenesis noninvasively when used with agents targeted vascular markers expressed by the angiogenic endothelium. Targeted agents, diameter on order of micrometers, cannot extravasate and therefore are solely receptors The aim this study was evaluate potential low-power sequence, Cadence(TM) pulse sequencing (CPS), combined angiogenesis.Targeted microbubbles were prepared conjugating echistatin via...
Microbubble contrast agents are widely used in ultrasound imaging and therapy, typically with transmission center frequencies the MHz range. Currently, an frequency near 250 kHz is proposed for clinical trials which combined microbubble applied to open blood brain barrier, since at this low focusing through human skull a predetermined location can be performed reduced distortion attenuation compared higher frequencies. However, vibrational response has not yet been carefully evaluated (an...
Transcranial ultrasound stimulation (TUS) has been shown to be a safe and effective technique for non-invasive superficial deep brain stimulation. Safe efficient translation humans requires estimating the acoustic attenuation of human skull. Nevertheless, there are no international guidelines impact skull bone. A tissue independent, arbitrary derating was developed by U.S. Food Drug Administration take into account absorption (0.3 dB/cm-MHz) diagnostic ultrasound. However, case transcranial...
Transcranial-focused ultrasound (tFUS) procedures such as neuromodulation and blood-brain barrier (BBB) opening require precise focus placement within the brain. MRI is currently most reliable tool for localization but can be prohibitive requiring recurrent therapies. We designed, fabricated, characterized a patient-specific, 3-D-printed, stereotactic frame repeated tFUS therapy. The compact, with minimal footprint, removed re-secured between treatments while maintaining sub-mm accuracy,...
Pain engages multiple brain networks, with the thalamus serving as a critical subcortical hub. This study aims to explore effects of low-intensity transcranial focused ultrasound-induced suppression on organization thalamocortical nociceptive networks. We employed MR-guided ultrasound, potential non-invasive therapy, real-time ultrasound beam localization feedback and fMRI monitoring. first functionally identified target at thalamic ventroposterior lateral nucleus by mapping whole-brain...
Abstract Non‐surgical and safe prostate cancer (PCa) therapies are in demand. Soluble tumor necrosis factor (TNF‐α) related apoptosis inducing ligand (TRAIL), a cancer‐specific drug, shows preclinical efficacy but has short circulation half‐life. This research shown that physiological fluid shear stress activates mechanosensitive ion channels (MSCs), such as Piezo1, enhancing TRAIL‐mediated cells. Herein, noninvasive, focal ultrasound (FUS) is implemented to augment the pro‐apoptotic effects...
Ultrasound contrast agents are often used to measure flow rate in the microvasculature; however, oscillation of these capillary-sized tubes has not been directly observed. Here, oscillations microbubbles examined microvessel phantoms with diameters similar those capillaries. High-speed camera images demonstrate effects ultrasonic pressure and tube diameter length on microbubble expansion fragmentation occurrence. Microbubble displacement due radiation force is also demonstrated a phantom microvessel.
Insonified microbubbles were observed in vessels within a gel with Young’s modulus similar to that of tissue, demonstrating shape instabilities, liquid jets, and the formation small tunnels. In this study, tunnel formulation occurred direction propagating ultrasound wave, where radiation pressure directed contact bubble gel, facilitating activity jets. Combinations ultrasonic parameters microbubble concentrations are relevant for diagnostic imaging drug delivery lead applied resulting was quantified.
Mild hyperthermia is increasingly important for the activation of temperature-sensitive drug delivery vehicles. Noninvasive ultrasound thermometry based on a 2-D speckle tracking algorithm was examined in this study. Here, commercial scanner, customized co-linear array transducer, and controlling PC system were used to generate mild hyperthermia. Because transducer capable both therapy imaging at widely separated frequencies, RF image frames acquired during therapeutic insonation then...
Our goal was to develop strategies quantify the accumulation of model therapeutics in small brain metastases using multimodal imaging, order enhance potential for successful treatment. Human melanoma cells were injected into left cardiac ventricle immunodeficient mice. Bioluminescent, MR and PET imaging applied evaluate limits detection contrast agent extravasation metastases. A pharmacokinetic estimate vascular permeability. Bioluminescent after injecting d-luciferin (molecular weight (MW)...
Transcranial focused ultrasound (FUS) is a non-invasive technique for therapy and study of brain neural activation. Here we report on the design characterization new MR-guided FUS transducer neuromodulation in non-human primates at 650 kHz. The array randomized with 128 elements 6.6 mm diameter, radius curvature 7.2 cm, opening diameter 10.3 cm (focal ratio 0.7), 46% coverage. Simulations were used to optimize geometry respect focus size, grating lobes, directivity. Focus size lobes during...