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Ultrasound phantom

William R Walter, Christopher J Burke, Mamadou Diallo, Ronald S Adler
We describe an easily constructed, customizable phantom for magnetic resonance imaging-ultrasound fusion imaging and demonstrate its role as a learning tool to initiate clinical use of this emerging modality. Magnetic resonance imaging-ultrasound fusion can prove unwieldy to integrate into routine practice. We demonstrate real-time fusion with single-sequence magnetic resonance imaging uploaded to the ultrasound console. Phantom training sessions allow radiologists and sonographers to practice fiducial marker selection and improve efficiency with the fusion hardware and software interfaces...
February 15, 2018: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
Ester Bonmati, Yipeng Hu, Barbara Villarini, Rachael Rodell, Paul Martin, Lianghao Han, Ian Donaldson, Hashim U Ahmed, Caroline M Moore, Mark Emberton, Dean C Barratt
PURPOSE: Image-guided systems that fuse magnetic resonance imaging (MRI) with three-dimensional (3D) ultrasound (US) images for performing targeted prostate needle biopsy and minimally-invasive treatments for prostate cancer are of increasing clinical interest. To date, a wide range of different accuracy estimation procedures and error metrics have been reported, which makes comparing the performance of different systems difficult. METHODS: A set of 9 measures are presented to assess the accuracy of MRI-US image registration, needle positioning, needle guidance, and overall system error, with the aim of providing a methodology for estimating the accuracy of instrument placement using a MR/US-guided transperineal approach...
February 14, 2018: Medical Physics
Theresa A Zwaschka, Justin S Ahn, Bryan W Cunitz, Michael R Bailey, Barbrina L Dunmire, Mathew D Sorensen, Jonathan D Harper, Adam D Maxwell
PURPOSE: Burst wave lithotripsy (BWL) is a new technology in development to fragment urinary stones. Ultrasonic propulsion is a separate technology under investigation for displacing stones. We measure the effect of propulsion pulses on stone fragmentation from BWL. MATERIAL/METHODS: Two artificial stone models (crystalline calcite, BegoStone plaster) and human calcium oxalate monohydrate stones measuring 5-8 mm were subjected to ultrasound exposures in a polyvinyl chloride tissue phantom within a water bath...
February 13, 2018: Journal of Endourology
Gary R Ge, Rosa Laimes, Joseph Pinto, Jorge Guerrero, Himelda Chavez, Claudia Salazar, Roberto J Lavarello, Kevin J Parker
The H-scan analysis of ultrasound images is a matched-filter approach derived from analysis of scattering from incident pulses in the form of Gaussian-weighted Hermite polynomial functions. This framework is applied in a preliminary study of thyroid lesions to examine the H-scan outputs for three categories: normal thyroid, benign lesions, and cancerous lesions within a total group size of 46 patients. In addition, phantoms comprised of spherical scatterers are analyzed to establish independent reference values for comparison...
January 2018: Journal of Medical Imaging
Yang Han, Thomas Payen, Shutao Wang, Elisa Konofagou
Harmonic motion imaging (HMI) is a radiation-force-based ultrasound elasticity imaging technique, which is designed for both tissue relative stiffness imaging and reliable high-intensity focused ultrasound treatment monitoring. The objective of this letter is to develop and demonstrate the feasibility of 2-D focused ultrasound (FUS) beam steering for HMI using a 93-element, FUS phased array. HMI with steered FUS beam was acquired in tissue-mimicking phantoms. The HMI displacement was imaged within the steering range of ±1...
February 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Philippe Paquette, Youssef El Khamlichi, Martin Lamontagne, Johanne Higgins, Dany H Gagnon
Background: Quantitative ultrasound imaging is gaining popularity in research and clinical settings to measure the neuromechanical properties of the peripheral nerves such as their capability to glide in response to body segment movement. Increasing evidence suggests that impaired median nerve longitudinal excursion is associated with carpal tunnel syndrome. To date, psychometric properties of longitudinal nerve excursion measurements using quantitative ultrasound imaging have not been extensively investigated...
August 2017: Ultrasound: Journal of the British Medical Ultrasound Society
Tsuicheng D Chiu, David Parsons, Yue Zhang, Brian Hrycushko, Bo Zhao, Rajiv Chopra, Nathan Kim, Ann Spangler, Asal Rahimi, Robert D Timmerman, Steve B Jiang, Weiguo Lu, Xuejun Gu
Accurate dose delivery in Stereotactic partial breast irradiation (S-PBI) is challenging because of the target position uncertainty caused by breast deformation, the target volume changes caused by lumpectomy cavity shrinkage, and target delineation uncertainty on simulation computed tomography (CT) images caused by poor soft tissue contrast. We have developed a volumetric ultrasound tomography (UST) image guidance system for prone position S-PBI. The system is composed of a novel 3D printed rotation water tank, a patient-specific resin breast immobilization cup, and a 1D array ultrasound transducer...
February 6, 2018: Physics in Medicine and Biology
Hyun Joo Shin, Myung-Joon Kim, Choon-Sik Yoon, Kwanseop Lee, Kwan Sik Lee, Jong-Chul Park, Mi-Jung Lee, Haesung Yoon
AIMS: To evaluate the differences between shear wave velocities (SWVs) measured with ultrasound elastography during the continuous motion using liver fibrosis phantoms. MATERIALS AND METHODS: Elasticities were measured with convex and linear transducers of supersonic shear wave imaging (SSI) and acoustic radiation force impulse imaging (ARFI) using liver elasticity phantoms (3.0 and 16.9 kPa) at depths of 2, 3, 4, and 5 cm. Motion velocities were 30 and 60 rpm with the phantoms in an upright position on the Orbital shaker...
February 4, 2018: Medical Ultrasonography
Giulia Matrone, Alessandro Ramalli, Piero Tortoli, Giovanni Magenes
Tissue Harmonic Imaging (THI) mode is currently one of the preferred choices by the clinicians for its ability to provide enhanced ultrasound images, thanks to the use of the second harmonic component of backscattered echoes. This paper aims at investigating whether the combination of THI with Filtered-Delay Multiply And Sum (F-DMAS) beamforming can provide further improvements in image quality. F-DMAS is a new non-linear beamformer, which, similarly to THI, is based on the use of the second harmonics of beamformed signals and is known to increase image contrast resolution and noise rejection...
January 4, 2018: Ultrasonics
Michael D Gray, Erasmia Lyka, Constantin C Coussios
Over the last decade, a variety of noninvasive techniques have been developed to monitor therapeutic ultrasound procedures in support of safety or efficacy assessments. One class of methods employs diagnostic ultrasound arrays to sense acoustic emissions, thereby providing a means to passively detect, localize, and quantify the strength of nonlinear sources, including cavitation. Real array element diffraction patterns may differ substantially from those presumed in existing beamforming algorithms. However, diffraction compensation has received limited treatment in passive and active imaging, and measured diffraction data have yet to be used for array response correction...
February 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Zhiqiang Zhang, Fei Li, Ruimin Chen, Tianfu Zhang, Xiaodong Cao, Shujun Zhang, Thomas R Shrout, Hairong Zheng, K Kirk Shung, Mark S Humayun, Weibao Qiu, Qifa Zhou
A modified Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) polycrystalline ceramic with ultrahigh relative clamped dielectric permittivity ( ) and high piezoelectric properties ( pC/N, ) was used to fabricate high-frequency miniature ultrasound transducers. A 39-MHz high-frequency ultrasound needle transducer with a miniature aperture of 0.4 mm mm was designed and successfully characterized. The fabricated needle transducer had an electromechanical coupling factor of 0.55, large bandwidth of 80% at -6 dB, and low insertion loss of -13 dB...
February 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Stefano Ricci, Alessandro Ramalli, Luca Bassi, Enrico Boni, Piero Tortoli
Quantitative blood velocity measurements, as currently implemented in commercial ultrasound scanners, are based on pulsed-wave (PW) spectral Doppler and are limited to detect the axial component of the velocity in a single sample volume. On the other hand, vector Doppler methods produce angle-independent estimates by, e.g., combining the frequency shifts measured from different directions. Moreover, thanks to the transmission of plane waves, the investigation of a 2-D region is possible with high temporal resolution, but, unfortunately, the clinical use of these methods is hampered by the massive calculation power required for their real-time execution...
February 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Zhishen Sun, Guoqiang Liu, Hui Xia, Stefan Catheline
Lorentz force electrical-impedance tomography (LFEIT) combines ultrasound stimulation and electromagnetic field detection with the goal of creating a high-contrast and high-resolution hybrid imaging modality. To reduce the peak stimulation power to the ultrasound transducer in LFEIT, linearly frequency-modulated (LFM) ultrasound pulse was investigated in this paper. First, the coherency between LFM ultrasound excitation and the resulting local current density was established theoretically. Then, experiments were done using different agar phantoms of conductivity ranging from 0...
February 2018: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
John D Mitchell, Rabia Amir, Mario Montealegre-Gallegos, Feroze Mahmood, Marc Shnider, Azad Mashari, Lu Yeh, Ruma Bose, Vanessa Wong, Philip Hess, Yannis Amador, Jelliffe Jeganathan, Stephanie B Jones, Robina Matyal
While standardized examinations and data from simulators and phantom models can assess knowledge and manual skills for ultrasound, an Objective Structured Clinical Examination (OSCE) could assess workflow understanding. We recruited 8 experts to develop an OSCE to assess workflow understanding in perioperative ultrasound. The experts used a binary grading system to score 19 graduating anesthesia residents at 6 stations. Overall average performance was 86.2%, and 3 stations had an acceptable internal reliability (Kuder-Richardson formula 20 coefficient >0...
January 29, 2018: Anesthesia and Analgesia
Gianluca Rigatelli, Marco Zuin, Fabio Dell'Avvocata, Dobrin Vassilev, Ramesh Daggubati, Thach Nguyen, Minh Trí Nhân Nguyễn, Nicolas Foin
OBJECTIVES: We assess the mid-term outcomes of ultrathin biodegradable polymer double stenting using a very minimal crushing (Nano-Crush) technique in large complex coronary bifurcation. BACKGROUND: Complex bifurcations have been suggested to be better approached by a planned double stent technique. METHODS: Two hundred and five consecutive patients (107 males and 98 females) referred for large complex coronary bifurcation percutaneous coronary interventions were enrolled...
January 25, 2018: Catheterization and Cardiovascular Interventions
Max Siekmann, Thomas Lothes, Ralph König, Christian Rainer Wirtz, Jan Coburger
PURPOSE: Currently, intraoperative ultrasound in brain tumor surgery is a rapidly propagating option in imaging technology. We examined the accuracy and resolution limits of different ultrasound probes and the influence of 3D-reconstruction in a phantom and compared these results to MRI in an intraoperative setting (iMRI). METHODS: An agarose gel phantom with predefined gel targets was examined with iMRI, a sector (SUS) and a linear (LUS) array probe with two-dimensional images...
January 24, 2018: International Journal of Computer Assisted Radiology and Surgery
Aiguo Han, Michael P Andre, Lisa Deiranieh, Elise Housman, John W Erdman, Rohit Loomba, Claude B Sirlin, William D O'Brien
OBJECTIVES: To assess the repeatability and reproducibility of the ultrasonic attenuation coefficient (AC) and backscatter coefficient (BSC) measured in the livers of adults with known or suspected nonalcoholic fatty liver disease (NAFLD). METHODS: The Institutional Review Board approved this Health Insurance Portability and Accountability Act-compliant prospective study; informed consent was obtained. Forty-one research participants with known or suspected NAFLD were recruited and underwent same-day ultrasound examinations of the right liver lobe with a clinical scanner by a clinical sonographer...
January 23, 2018: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
Kathyayini Sivasubramanian, Vijitha Periyasamy, Rhonnie Austria Dienzo, Manojit Pramanik
Urinary bladder imaging is critical to diagnose urinary tract disorders, and bladder cancer. There is a great need for safe, non-invasive, and sensitive imaging technique which enables bladder imaging. Photoacoustic imaging is a rapidly growing imaging technique for various biological applications. It can be combined with clinical ultrasound imaging system for hand-held, dual modal ultrasound-photoacoustic real-time imaging. Structural (bladder wall) and functional (accretion of nanoparticles) bladder imaging is shown here with combined ultrasound and photoacoustic imaging in rats...
January 17, 2018: Journal of Biophotonics
Zaiyang Long, Donald J Tradup, Scott F Stekel, Krzysztof R Gorny, Nicholas J Hangiandreou
We evaluated a commercially available software package that uses B-mode images to semi-automatically measure quantitative metrics of ultrasound image quality, such as contrast response, depth of penetration (DOP), and spatial resolution (lateral, axial, and elevational). Since measurement of elevational resolution is not a part of the software package, we achieved it by acquiring phantom images with transducers tilted at 45 degrees relative to the phantom. Each measurement was assessed in terms of measurement stability, sensitivity, repeatability, and semi-automated measurement success rate...
January 16, 2018: Journal of Applied Clinical Medical Physics
Amy S Yu, Mohammad Najafi, Dimitre H Hristov, Tiffany Phillips
PURPOSE: The aim of this study is to evaluate the tracking accuracy of a commercial ultrasound system under relevant treatment conditions and demonstrate its clinical utility for detecting significant treatment deviations arising from inadvertent intrafractional target motion. METHODS: A multimodality male pelvic phantom was used to simulate prostate image-guided radiotherapy with the system under evaluation. Target motion was simulated by placing the phantom on a motion platform...
December 2017: Technology in Cancer Research & Treatment
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