keyword
MENU ▼
Read by QxMD icon Read
search

Ultrasound phantom

keyword
https://www.readbyqxmd.com/read/28732948/real-time-monitoring-of-controllable-cavitation-erosion-in-a-vessel-phantom-with-passive-acoustic-mapping
#1
Shukuan Lu, Aiwei Shi, Bowen Jing, Xuan Du, Mingxi Wan
Cavitation erosion in blood vessel plays an important role in ultrasound thrombolysis, drug delivery, and other clinical applications. The controllable superficial vessel erosion based on ultrasonic standing wave (USW) has been used to effectively prevent vessel ruptures and haemorrhages, and optical method is used to observe the experiments. But optical method can only work in transparent media. Compared with standard B-mode imaging, passive acoustic mapping (PAM) can monitor erosion in real time and has better sensitivity of cavitation detection...
November 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28728780/detecting-regional-stiffness-changes-in-aortic-aneurysmal-geometries-using-pressure-normalized-strain
#2
Doran S Mix, Ling Yang, Camille C Johnson, Nathan Couper, Ben Zarras, Isaac Arabadjis, Lauren E Trakimas, Michael C Stoner, Steven W Day, Michael S Richards
Transabdominal ultrasound elasticity imaging could improve the assessment of rupture risk for abdominal aortic aneurysms by providing information on the mechanical properties and stress or strain states of vessel walls. We implemented a non-rigid image registration method to visualize the pressure-normalized strain within vascular tissues and adapted it to measure total strain over an entire cardiac cycle. We validated the algorithm's performance with both simulated ultrasound images with known principal strains and anatomically accurate heterogeneous polyvinyl alcohol cryogel vessel phantoms...
July 17, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28727616/iterative-reconstruction-may-improve-diagnosis-of-gout-an-ex-vivo-bio-phantom-dual-energy-computed-tomography-study
#3
Torsten Diekhoff, Maximilian Kotlyarov, Jürgen Mews, Bernd Hamm, Kay-Geert Armin Hermann
OBJECTIVES: We hypothesize that, compared with filtered back projection (FBP), iterative reconstruction (IR) increases the detected volume of uric acid, which serves as a measure of the sensitivity of the method, and therefore allows examinations with lower radiation exposure. Thus, the aim of our study was to evaluate the role of IR in dual-energy computed tomography (DECT) for gout assessment and volumetry in an ex vivo gout model using an epoxy phantom and a biophantom. MATERIALS AND METHODS: We prepared specimens with different concentrations of monosodium uric acid in ultrasound gel (30%-50%) and inserted them into an epoxy-based phantom and a porcine foreleg...
July 19, 2017: Investigative Radiology
https://www.readbyqxmd.com/read/28718774/effects-of-microchannel-confinement-on-acoustic-vaporisation-of-ultrasound-phase-change-contrast-agents
#4
Shengtao Lin, Ge Zhang, Chee Hau Leow, Meng-Xing Tang
The sub-micron phase change contrast agent (PCCA) composed of a perfluorocarbon liquid core can be activated into gaseous state and form stable echogenic microbubbles for contrast-enhanced ultrasound imaging. It has shown great promises in imaging microvasculature, tumour microenvironment, and cancer cells. Although PCCAs have been extensively studied for different diagnostic and therapeutic applications, the effect of biologically geometrical confinement on the acoustic vaporisation of PCCAs is still not clear...
July 18, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28718001/a-new-device-for-fiducial-registration-of-image-guided-navigation-system-for-liver-rfa
#5
Nobutaka Doba, Hiroyuki Fukuda, Kazushi Numata, Yoshiteru Hao, Kouji Hara, Akito Nozaki, Masaaki Kondo, Makoto Chuma, Katsuaki Tanaka, Shigeo Takebayashi, Norihiro Koizumi, Akira Kobayashi, Junichi Tokuda, Shin Maeda
PURPOSE: Radiofrequency ablation for liver tumors (liver RFA) is widely performed under ultrasound guidance. However, discriminating between the tumor and the needle is often difficult because of cavitation caused by RFA-induced coagulation. An unclear ultrasound image can lead to complications and tumor residue. Therefore, image-guided navigation systems based on fiducial registration have been developed. Fiducial points are usually set on a patient's skin. But the use of internal fiducial points can improve the accuracy of navigation...
July 17, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28715339/development-of-a-low-cost-medical-ultrasound-scanner-using-a-monostatic-synthetic-aperture
#6
Thomas L A van den Heuvel, David J Graham, Kristopher J Smith, Chris L de Korte, Jeffrey A Neasham
OBJECTIVE: In this paper, we present the design of low-cost medical ultrasound scanners aimed at the detection of maternal mortality risk factors in developing countries. METHOD: Modern ultrasound scanners typically employ a high element count transducer array with multichannel transmit and receive electronics. To minimize hardware costs, we employ a single piezoelectric element, mechanically swept across the target scene, and a highly cost-engineered single channel acquisition circuit...
July 17, 2017: IEEE Transactions on Biomedical Circuits and Systems
https://www.readbyqxmd.com/read/28714565/mri-compatible-breast-rib-phantom-for-evaluating-ultrasonic-thermal-exposures
#7
Georgios Menikou, Marinos Yiannakou, Christos Yiallouras, Cleanthis Ioannides, Christakis Damianou
INTRODUCTION: The target of this study was the development of a magnetic resonance imaging (MRI) compatible breast phantom for focused ultrasound which includes plastic (ABS) ribs. The objective of the current study was the evaluation of a focused ultrasound procedure using the proposed phantom that eliminates rib heating. MATERIAL AND METHODS: The proposed phantom was evaluated using two different focused ultrasound exposures. The surrounding breast tissue was mimicked using an agar-silica-evaporation milk gel (2% w/v - 2% w/v - 40% v/v)...
July 17, 2017: International Journal of Medical Robotics + Computer Assisted Surgery: MRCAS
https://www.readbyqxmd.com/read/28711187/development-of-an-in-vitro-diaphragm-motion-reproduction-system
#8
Ai-Ho Liao, Ho-Chiao Chuang, Ming-Chih Shih, Hsiao-Yu Hsu, Der-Chi Tien, Chia-Chun Kuo, Shiu-Chen Jeng, Jeng-Fong Chiou
This study developed an in vitro diaphragm motion reproduction system (IVDMRS) based on noninvasive and real-time ultrasound imaging to track the internal displacement of the human diaphragm and diaphragm phantoms with a respiration simulation system (RSS). An ultrasound image tracking algorithm (UITA) was used to retrieve the displacement data of the tracking target and reproduce the diaphragm motion in real time using a red laser to irradiate the diaphragm phantom in vitro. This study also recorded the respiration patterns in 10 volunteers...
July 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28708733/an-assembled-prototype-multimaterial-three-dimensional-printed-model-of-the-neck-for-computed-tomography-and-ultrasound-guided-interventional-procedures
#9
Ramin Javan, Alexander L Cho
A low-cost, semirealistic, multimaterial prototype phantom of the neck was developed for computed tomography- and ultrasound-guided interventions, using three-dimensional (3D) printing with a variety of materials as well as through molding techniques. This dual-modality phantom can be used by trainees for practicing procedures and can also serve as a prototype for developing more complex and realistic 3D-printed models, particularly with the continued development and advancement in multimaterial 3D printing technologies...
July 13, 2017: Journal of Computer Assisted Tomography
https://www.readbyqxmd.com/read/28706440/reliability-of-an-integrated-ultrasound-and-stereophotogrammetric-system-for-lower-limb-anatomical-characterisation
#10
Frederick Greatrex, Erica Montefiori, Thomas Grupp, Josef Kozak, Claudia Mazzà
BACKGROUND: Lower extremity analysis for preoperative total knee and hip arthroplasty routines can increase surgery success rate and hence reduce associated costs. Current tools are limited by being invasive, limited to supine analysis, or too expensive. This study aimed to propose and validate a device, OrthoPilot®, based on the combined use of a stereophotogrammetric and ultrasound system which can in vivo and noninvasively measure varus/valgus, flexion/extension, femur and tibia torsion, and femur and tibia lengths...
2017: Applied Bionics and Biomechanics
https://www.readbyqxmd.com/read/28702635/the-mechanism-of-nanoparticle-mediated-enhanced-energy-transfer-during-high-intensity-focused-ultrasound-sonication
#11
Chandan Bera, Surendra B Devarakonda, Vishal Kumar, Ashok K Ganguli, Rupak K Banerjee
In this combined experimental and theoretical research, magnetic nano-particle (mNP) mediated energy transfer due to high intensity-focused ultrasound (HIFU) sonication has been evaluated. HIFU sonications have been performed on phantoms containing three different volume percentages (0%, 0.0047%, and 0.047%) of mNPs embedded in a tissue mimicking material (TMM). A theoretical model has been developed to calculate the temperature rise in the phantoms during HIFU sonication. It is observed from theoretical calculation that the phonon layer at the interface of the mNPs and TMM dominates the attenuation for higher (0...
July 12, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28700131/high-intensity-focused-ultrasound-hifu-and-phase-sensitive-optical-coherence-tomography-phs-oct-for-high-resolution-surface-acoustic-wave-saw-elastography
#12
Kanheng Zhou, Nhan Le, Zhihong Huang, Chunhui Li
Elastography has the ability of quantitatively evaluating the mechanical properties of soft tissue, thus is helpful for diagnosis and treatment monitoring for many diseases, e.g. skin diseases. Surface acoustic waves (SAWs) have been proven to be a non-invasive, non-destructive method for accurate characterization of tissue elastic properties. Current surface acoustic wave elastography using high energy laser pulse or mechanical shaker still have some problems. In order to improve SAW elastography in medical application, a new technique was proposed in this paper, which combines high intensity focused ultrasound (HIFU) as a SAWs impulse inducer and PhS-OCT as a SAWs detector...
July 12, 2017: Journal of Biophotonics
https://www.readbyqxmd.com/read/28693905/a-temporal-and-spatial-analysis-approach-to-automated-segmentation-of-microbubble-signals-in-contrast-enhanced-ultrasound-images-application-to-quantification-of-active-vascular-density-in-human-lower-limbs
#13
Wing Keung Cheung, Katherine J Williams, Kirsten Christensen-Jeffries, Brahman Dharmarajah, Robert J Eckersley, Alun H Davies, Meng-Xing Tang
Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents has shown great promise in visualising and quantifying active vascular density. Most existing approaches for vascular density quantification using CEUS are calculated based on image intensity and are susceptible to confounding factors and imaging artefact. Poor reproducibility is a key challenge to clinical translation. In this study, a new automated temporal and spatial signal analysis approach is developed for reproducible microbubble segmentation and quantification of contrast enhancement in human lower limbs...
July 7, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28692957/passive-wearable-skin-patch-sensor-measures-limb-hemodynamics-based-on-electromagnetic-resonance
#14
Kim Cluff, Ryan A Becker, Balakumar Jayakumar, Kiyun Han, Ernie Condon, Kenneth Dudley, George Szatkowski, Iraklis I Pipinos, Ryan Z Amick, Jeremy Patterson
OBJECTIVE: The objectives of this study were to design and develop an open circuit electromagnetic resonant skin patch sensor, characterize the fluid volume and resonant frequency relationship and investigate the sensor's ability to measure limb hemodynamics and pulse volume waveform features. METHODS: The skin patch was designed from an open circuit electromagnetic resonant sensor comprised of a single baseline trace of copper configured into a square planar spiral which had a self-resonating response when excited by an external radio frequency (RF) sweep...
July 4, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28692857/modelling-and-extraction-of-pulsatile-radial-distension-and-compression-motion-for-automatic-vessel-segmentation-from-video
#15
Alborz Amir-Khalili, Ghassan Hamarneh, Rafeef Abugharbieh
Identification of vascular structures from medical images is integral to many clinical procedures. Most vessel segmentation techniques ignore the characteristic pulsatile motion of vessels in their formulation. In a recent effort to automatically segment vessels that are hidden under fat, we motivated the use of the magnitude of local pulsatile motion extracted from surgical endoscopic video. In this article we propose a new approach that leverages the local orientation, in addition to magnitude of motion, and demonstrate that the extended computation and utilization of motion vectors can improve the segmentation of vascular structures...
June 29, 2017: Medical Image Analysis
https://www.readbyqxmd.com/read/28692762/nanoscale-ultrasound-switchable-fret-based-liposomes-for-near-infrared-fluorescence-imaging-in-optically-turbid-media
#16
Qimei Zhang, Stephen P Morgan, Melissa L Mather
A new approach for fluorescence imaging in optically turbid media centered on the use of nanoscale ultrasound-switchable FRET-based liposome contrast agents is reported. Liposomes containing lipophilic carbocyanine dyes as FRET pairs with emission wavelengths located in the near-infrared window are prepared. The efficacy of FRET and self-quenching for liposomes with a range of fluorophore concentrations is first calculated from measurement of the liposome emission spectra. Exposure of the liposomes to ultrasound results in changes in the detected fluorescent signal, the nature of which depends on the fluorophores used, detection wavelength, and the fluorophore concentration...
July 10, 2017: Small
https://www.readbyqxmd.com/read/28688115/a-monte-carlo-study-of-the-effect-of-an-ultrasound-transducer-on-surface-dose-during-intrafraction-motion-imaging-for-external-beam-radiation-therapy
#17
Michael Martyn, Tuathan O'Shea, Emma Harris, Jeffrey Bamber, Stephen Gilroy, Mark J Foley
PURPOSE: To estimate changes in surface dose due to the presence of the Clarity Autoscan(™) ultrasound (US) probe during prostate radiotherapy using Monte Carlo (MC) methods. METHODS: MC models of the Autoscan US probe were developed using the BEAMnrc/DOSXYZnrc code based on kV and MV CT images. CT datasets were converted to voxelized mass density phantoms using a CT number-to-mass density calibration. The dosimetric effect of the probe, in the contact region (an 8 mm x 12 mm single layer of voxels), was investigated using a phantom set-up mimicking two scenarios (i) a transperineal imaging configuration (radiation beam perpendicular to the central US axial direction), and (ii) a transabdominal imaging configuration (radiation beam parallel to the central US axial direction)...
July 8, 2017: Medical Physics
https://www.readbyqxmd.com/read/28680156/miniature-probe-for-mapping-mechanical-properties-of-vascular-lesions-using-acoustic-radiation-force-optical-coherence-elastography
#18
Yueqiao Qu, Teng Ma, Youmin He, Mingyue Yu, Jiang Zhu, Yusi Miao, Cuixia Dai, Pranav Patel, K Kirk Shung, Qifa Zhou, Zhongping Chen
Cardiovascular diseases are the leading cause of fatalities in the United States. Atherosclerotic plaques are one of the primary complications that can lead to strokes and heart attacks if left untreated. It is essential to diagnose the disease early and distinguish vulnerable plaques from harmless ones. Many methods focus on the structural or molecular properties of plaques. Mechanical properties have been shown to change drastically when abnormalities develop in arterial tissue. We report the development of an acoustic radiation force optical coherence elastography (ARF-OCE) system that uses an integrated miniature ultrasound and optical coherence tomography (OCT) probe to map the relative elasticity of vascular tissues...
July 5, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28670990/compressed-sensing-for-elastography-in-portable-ultrasound
#19
Bonghun Shin, Soo Jeon, Jeongwon Ryu, Hyock Ju Kwon
Portable ultrasound is recently emerging as a new medical imaging modality featuring high portability, easy connectivity, and real-time on-site diagnostic ability. However, it does not yet provide ultrasound elastography function that enables the diagnosis of malignant lesions using elastic properties. This is mainly due to the limitations of hardware performance and wireless data transfer speed for processing the large amount of data for elastography. Therefore, data transfer reduction is one of the feasible solutions to overcome these limitations...
June 1, 2017: Ultrasonic Imaging
https://www.readbyqxmd.com/read/28669429/hybrid-photoacoustic-ultrasound-tomograph-for-real-time-finger-imaging
#20
Milan Oeri, Wolfgang Bost, Nicolas Sénégond, Steffen Tretbar, Marc Fournelle
We report a target-enclosing, hybrid tomograph with a total of 768 elements based on capacitive micromachined ultrasound transducer technology and providing fast, high-resolution 2-D/3-D photoacoustic and ultrasound tomography tailored to finger imaging. A freely programmable ultrasound beamforming platform sampling data at 80 MHz was developed to realize plane wave transmission under multiple angles. A multiplexing unit enables the connection and control of a large number of elements. Fast image reconstruction is provided by GPU processing...
June 29, 2017: Ultrasound in Medicine & Biology
keyword
keyword
117225
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"