A5071870380- Ultrasound Imaging and Elastography
- Ultrasonics and Acoustic Wave Propagation
- Electrical and Bioimpedance Tomography
- Photoacoustic and Ultrasonic Imaging
- Thermography and Photoacoustic Techniques
- Optical Imaging and Spectroscopy Techniques
- Acoustic Wave Resonator Technologies
- Microwave Imaging and Scattering Analysis
- Antenna Design and Optimization
- Microwave Engineering and Waveguides
- Cardiovascular Disease and Adiposity
- Piezoelectric Actuators and Control
- Bacterial Infections and Vaccines
- Dysphagia Assessment and Management
- Glioma Diagnosis and Treatment
- Flow Measurement and Analysis
- Advanced MEMS and NEMS Technologies
- Peptidase Inhibition and Analysis
- High Altitude and Hypoxia
- Microwave and Dielectric Measurement Techniques
- Viral-associated cancers and disorders
- Cancer Genomics and Diagnostics
- Diverse Musicological Studies
- RNA regulation and disease
- Microfluidic and Bio-sensing Technologies
Purdue University West Lafayette
2025
Massachusetts General Hospital
2023-2024
Harvard University
2024
Dalhousie University
2014-2021
Greater Baltimore Medical Center
2016
<title>Abstract</title> Hypoxia is a common feature of arterial hypertension that does not consistently elevate blood pressure (BP), but triggers exaggerated increases in muscle sympathetic nerve activity (MSNA) and may disturb transduction baroreflex sensitivity hypertensive individuals. Elevated resting MSNA, enhanced transduction, reduced are all associated with increased variability (BPV), marker target organ damage independent absolute BP levels. We hypothesized hypoxia would elicit...
A novel 3D photoacoustic imaging technique is experimentally demonstrated using a 64×64 element bias-sensitive crossed-electrode relaxor array. This allows for large 2D arrays to receive across all elements while minimal channel counts. Hadamard-bias patterns are applied column electrodes signals measured from row electrodes. Photoacoustic crossed-wire phantom in an intralipid scattering medium. The Hadamard-bias-encoded scheme showed signal-to-noise (SNR) of 25.3 dB, the single-column...
Three-dimensional ultrasound imaging presents technical challenges of addressing large numbers elements in 2D array transducers. Top-Orthogonal to Bottom Electrode (TOBE) transducer arrays can simplify but typical methods with such enable only one-way focusing azimuth and elevation. Here experimental results are reported for the Fast Orthogonal Row-Column Electronic Scanning (FORCES) scheme implemented on a 64 ×64 element bias-sensitive electrostrictive relaxor TOBE array. The FORCES...
This work describes the design, fabrication, and characterization of a 128-element crossed electrode array in miniature endoscopic form factor for real-time 3-D imaging. Crossed arrays address some key challenges surrounding probe fabrication ultrasound imaging by reducing number elements required (2N compared with N2). However, there remain practical packaging high-frequency into an factor. A process has been developed that uses thinly diced strip flex circuit to bring back-side connections...
We have developed a new, fast, and simple 3-D imaging approach referred to as Simultaneous Azimuth Fresnel Elevation (SAFE) compounding using bias-sensitive crossed-electrode array. The principle behind this technique is perform conventional plane-wave with back set of electrodes, while implementing reconfigurable elevation lens an orthogonal front electrodes. While would usually result in unacceptable secondary lobe levels, these lobes can be suppressed by different patterns. azimuthal...
Here we introduce electrostrictive hot-pressed lead magnesium niobate (PMN) with low titanate (PT) doping as a candidate transparent transducer material. We fabricate high-frequency single-element transducers and characterize their optical, electrical, acoustic properties. PMN-PT may offer sensitivity advantages over other materials such lithium owing to its high electromechanical efficiency bias-voltage sensitivity. The transparency of the fabricated was measured ∼67% at 532 nm wavelength...
A reconfigurable Fresnel lens approach for 3D imaging on crossed electrode array is described. can provide a focus comparable to traditional beamforming if the used in one direction, combined with conventional other direction. For example, azimuth pattern applied transmit and dynamic completed receive. second feature our design arises from fact that although create tight lateral focus, inherently long axial pulses result poor resolution. This because phase delays are quantized 0 or 180...
We have developed a new, fast and simple 3D imaging approach referred to as Simultaneous Azimuth Fresnel Elevation (SAFE) compounding. The principle behind this technique is perform conventional plane wave compounding with the bottom set of electrodes, while implementing reconfigurable elevation lens top electrodes. While would usually result in unacceptable secondary lobe levels, these lobes can be suppressed by different patterns. azimuthal elevational planes simultaneously compounded...
Crossed electrode arrays address some of the challenges associated with 3-D ultrasound imaging because significant reduction in number elements ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2{N}$ </tex-math></inline-formula> versus notation="LaTeX">${N}^{{2}}$ ). However, creating a two-way focused image real time is difficult these azimuth and elevation dimensions cannot be beamformed at same time....
We introduce novel bias-sensitive piezoelectric transducer (relaxor) arrays for 3D photoacoustic imaging. A 64×64 element relaxor array using a crossed electrode or Top-Orthogonal to Bottom-Electrode (TOBE) wiring configuration is used receive data from two wires with 17.8 um diameters in an intralipid medium. image was then reconstructed. By biasing column and receiving along row, individual elements can be isolated readout of signals all bias-switching-based multiplexing. demonstrate...
A set of prototype RF delay lines have been developed in order to meet the required bandwidth, accuracy, and range requirements for a previously 64 channel endoscopic phased array prototype. Each line is based on planar PMN-32%PT pulse-echo transducer situated water bath, reflecting off polished brass reflector. The transducers are mounted individual in-house fabricated piezoelectric bimorphs, which 'simply' supported. This creates an electronic time proportional distance between...
3D Ultrasound systems present several technical challenges, particularly the large number of elements in a 2D array, high electrical impedance, and image acquisition time. Crossed electrode arrays address some these issues, especially huge reduction elements. However, creating two-way focused real-time is difficult with because azimuth elevation dimensions cannot be beamformed at same This typically forces one to use synthetic aperture approach which inherently slow requires increased...
This article aims to establish the relationship between pathologic diagnosis and rate of success in cancer next-generation sequencing testing.Clinical results performed for solid tumors were reviewed. The was analyzed context tumor type accompanying variables.Out 683 total specimens, 533 (78.0%) underwent successful sequencing. 91.8% ovarian carcinomas, 87.5% lung non-small cell 82.0% colorectal adenocarcinomas, 78.3% melanomas, 75.9% breast 64.7% pancreatic adenocarcinomas. For specimens...
Crossed electrode arrays address some the challenges associated with 3D ultrasound imaging because of significant reduction in number elements (2N vs. N <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ). However, creating a two-way focused image real-time is difficult these azimuth and elevation dimensions cannot be beamformed at same time. We have developed new approach that uses flexibility bias sensitive substrates to create...
A digital variable sampling high-frequency beamformer implementing real-time grating lobe suppression is described. The system tested using a semi-kerfed 64 element 45 MHz phased array with 1λ pitch. facilitated the sign coherence factor (SCF) and split-aperture transmit beamforming techniques. new technique called "sub-aperture probing" (SAP) described, experimentally validated, compared to previously developed techniques respect suppression. Grating levels were suppressed be 49 60 dB below...
A new technique for 3-D imaging with a row-column array (RCA) configuration has been developed. The requires an electrostrictive piezoelectric the active substrate. While top set of electrodes is connected to RF transmit and receive channels conventional diverging wave (DWI), orthogonal bottom independently controlled variable dc bias channels. By implementing modulated patterns compounded across multiple pulses, fine delay control elements can be achieved simultaneously electrodes. This...
Pancreatic cancer (PDAC) has a poor prognosis and limited treatment options. Focused ultrasound shown potential for improving PDAC outcomes by enhancing drug delivery through acoustic cavitation. In this work, we present the development of an early prototype endoscopic device capable producing high focal pressure with imaging guidance. Ongoing research aim to further improve explore its as potentiator chemotherapeutic PDAC.
This work describes the design, fabrication and characterization of a 128-element crossed electrode array in miniature endoscopic form factor. Crossed arrays address some key challenges surrounding probe for 3D ultrasound imaging by reducing number elements required (2N compared to N <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ). However, there remain practical packaging high-frequency into an A process has been developed that uses...
A new image acquisition scheme is presented that optimized for applications require channel-limited transducers such as IVUS. During acquisition, both the transmit and receive apertures are dynamically phase-encoded with a set of orthogonal (Hadamard) codes. The transducer's excitation data collection handled on single RF channel. Simulations using Field II software package showed an 18 dB improvement in SNR when compared to synthetic aperture technique which multiplexes elements into 30 MHz...