keyword
MENU ▼
Read by QxMD icon Read
search

Ultrasound phantom

keyword
https://www.readbyqxmd.com/read/28545859/cardiac-shear-wave-elastography-using-a-clinical-ultrasound-system
#1
Mihai Strachinaru, Johan G Bosch, Bas M van Dalen, Lennart van Gils, Antonius F W van der Steen, Nico de Jong, Marcel L Geleijnse, Hendrik J Vos
The propagation velocity of shear waves relates to tissue stiffness. We prove that a regular clinical cardiac ultrasound system can determine shear wave velocity with a conventional unmodified tissue Doppler imaging (TDI) application. The investigation was performed on five tissue phantoms with different stiffness using a research platform capable of inducing and tracking shear waves and a clinical cardiac system (Philips iE33, achieving frame rates of 400-700 Hz in TDI by tuning the normal system settings)...
May 22, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28543374/ultrasound-phantom-using-sodium-alginate-as-a-gelling-agent
#2
Minoru Aoyagi, Tomomi Hiraguri
For medical workers, ultrasound phantoms for human soft tissue are used not only for accuracy management of ultrasound diagnosis but also to aid ultrasound-guided needle and blind catheter insertion training without risk to real patients. For the phantoms, ultrasound characteristics and a texture are required to mimic the human soft tissue. The proposed phantom was composed of sodium alginate, calcium sulfate dihydrate, trisodium phosphate 12-hydrate, glycerol, and water. The propagation speed, attenuation coefficient, acoustic impedance, and texture of the proposed phantom were almost the same as those of human soft tissue...
May 23, 2017: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/28542716/improving-needle-tip-identification-during-ultrasound-guided-procedures-in-anaesthetic-practice
#3
REVIEW
H J Scholten, A Pourtaherian, N Mihajlovic, H H M Korsten, R A Bouwman
Ultrasound guidance is becoming standard practice for needle-based interventions in anaesthetic practice, such as vascular access and peripheral nerve blocks. However, difficulties in aligning the needle and the transducer can lead to incorrect identification of the needle tip, possibly damaging structures not visible on the ultrasound screen. Additional techniques specifically developed to aid alignment of needle and probe or identification of the needle tip are now available. In this scoping review, advantages and limitations of the following categories of those solutions are presented: needle guides; alterations to needle or needle tip; three- and four-dimensional ultrasound; magnetism, electromagnetic or GPS systems; optical tracking; augmented (virtual) reality; robotic assistance; and automated (computerised) needle detection...
May 22, 2017: Anaesthesia
https://www.readbyqxmd.com/read/28541897/capacitive-micro-machined-ultrasound-transducers-for-interstitial-high-intensity-ultrasound-therapies
#4
W Apoutou N'Djin, Bjoern Gerold, Jeremy Vion, Michael Canney, An Nguyen-Dinh, Alexandre Carpentier, Jean-Yves Chapelon
Capacitive Micro-machined Ultrasound Transducers (CMUTs) exhibit several potential advantages over conventional piezo technologies for use in therapeutic ultrasound devices, including: ease of miniaturization and integration with electronics, broad bandwidth (>several MHz), and compatibility with magnetic resonance imaging (MRI). In this work, the electro-acoustic performance of CMUTs designed for interstitial high intensity contact ultrasound (HICU) applications was evaluated and the feasibility of generating ultrasound-induced heating and thermal destruction of biological tissues was studied...
May 24, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28541199/3d-nonlinear-acoustic-inverse-scattering-algorithm-and-quantitative-results
#5
James Wiskin, David Borup, Elaine Iuanow, John Klock, Mark Lenox
We describe a novel 3D ultrasound technology, the Quantitative Transmission Ultrasound (QT Ultrasound®) system and algorithm to image a pendent breast in a water bath. Quantitative accuracy is verified using phantoms. Morphological accuracy is verified using cadaveric breast and in vivo images, and spatial resolution is estimated. This paper generalizes an earlier 2D algorithm to a full 3D inversion algorithm and shows the importance of such a 3D algorithm for artifact suppression as compared with the 2D algorithm...
May 23, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28541198/combined-pulse-echo-ultrasound-and-multispectral-optoacoustic-tomography-with-a-multi-segment-detector-array
#6
Elena Mercep, X Luis Dean Ben, Daniel Razansky
The high complementarity of ultrasonography and optoacoustic tomography has prompted the development of combined approaches that utilize the same transducer array for detecting both optoacoustic and pulse-echo ultrasound responses from tissues. Yet, due to the fundamentally different physical contrast and image formation mechanisms, the development of detection technology optimally suited for image acquisition in both modalities remains a major challenge. Herein, we introduce a multi-segment detector array approach incorporating array segments of linear and concave geometry to optimally support both ultrasound and optoacoustic image acquisition...
May 18, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28534769/a-systematic-investigation-of-lateral-estimation-using-various-interpolation-approaches-in-conventional-ultrasound-imaging
#7
Zhi Liu, Chengwu Huang, Jianwen Luo
Accurate lateral displacement and strain estimat- ion is critical for some applications of elasticity imaging. Typically, motion estimation in the lateral direction is challenging because of low sampling frequency and lack of phase information in conventional ultrasound imaging. Several approaches have been proposed to improve the performance of lateral estimation, such as lateral interpolation on the RF signals (Interp_RF), lateral interpolation on the cross-correlation function (Interp_CCF) and lateral interpolation on both the RF signals and cross-correlation function (Interp_Both)...
May 17, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28530205/phantom-experiments-using-soft-prior-regularization-eit-for-breast-cancer-imaging
#8
Ethan K Murphy, Aditya Mahara, Xiaotian Wu, Ryan J Halter
OBJECTIVE: A soft-prior regularization (SR) electrical impedance tomography (EIT) technique for breast cancer imaging is described, which shows an ability to accurately reconstruct tumor/inclusion conductivity values within a dense breast model investigated using a cylindrical and a breast-shaped tank. APPROACH: The SR-EIT method relies on knowing the spatial location of a suspicious lesion initially detected from a second imaging modality. Standard approaches (using Laplace smoothing and total variation regularization) without prior structural information are unable to accurately reconstruct or detect the tumors...
June 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28523284/enhanced-axial-and-lateral-resolution-using-stabilized-pulses
#9
Shujie Chen, Kevin J Parker
Ultrasound B-scan imaging systems operate under some well-known resolution limits. To improve resolution, the concept of stable pulses, having bounded inverse filters, was previously utilized for the lateral deconvolution. This framework has been extended to the axial direction, enabling a two-dimensional deconvolution. The modeling of the two-way response in the axial direction is discussed, and the deconvolution is performed in the in-phase quadrature data domain. Stable inverse filters are generated and applied for the deconvolution of the image data from Field II simulation, a tissue-mimicking phantom, and in vivo imaging of a carotid artery, where resolution enhancement is observed...
April 2017: Journal of Medical Imaging
https://www.readbyqxmd.com/read/28516051/evaluation-of-mr-thermometry-with-proton-resonance-frequency-method-at-7t
#10
Ping Wang
Quantitative and non-invasive temperature mapping using magnetic resonance imaging (MRI) provides a unique way to measure temperature evolution inside biological tissues. The method is widely used in thermal ablation procedures with magnetic fields at or below 3T. In this paper, the sensitivity of the MRI thermometry at 7T was studied using a proton resonance frequency (PRF)-based technique. We first used an agarose gel phantom with MR-compatible thermometry to calibrate the temperature coefficient, and then this temperature coefficient was employed to measure the internal temperature in both ex vivo (beef muscle) and in vivo (rat) experiments using focused ultrasound heating...
April 2017: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/28504935/efficient-three-dimensional-model-based-reconstruction-scheme-for-arbitrary-optoacoustic-acquisition-geometries
#11
Lu Ding, X Luis Dean Ben, Daniel Razansky
Optimal optoacoustic tomographic sampling is often hindered by the frequency-dependent directivity of ultrasound sensors, which can only be accounted for with an accurate three-dimensional (3D) model. Herein, we introduce a 3D modelbased reconstruction method applicable to optoacoustic imaging systems employing detection elements with arbitrary size and shape. The computational complexity and memory requirements are mitigated by introducing an efficient graphics processing unit (GPU)-based implementation of the iterative inversion...
May 12, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28504278/high-frequency-linear-rheology-of-hydrogels-probed-by-ultrasound-driven-microbubble-dynamics
#12
Akaki Jamburidze, Marco De Corato, Axel Huerre, Angelo Pommella, Valeria Garbin
Ultrasound-driven microbubble dynamics are central to biomedical applications, from diagnostic imaging to drug delivery and therapy. In therapeutic applications, the bubbles are typically embedded in tissue, and their dynamics are strongly affected by the viscoelastic properties of the soft solid medium. While the behaviour of bubbles in Newtonian fluids is well characterised, a fundamental understanding of the effect on ultrasound-driven bubble dynamics of a soft viscoelastic medium is still being developed...
May 15, 2017: Soft Matter
https://www.readbyqxmd.com/read/28494102/non-invasive-carotid-artery-elastography-using-multi-element-synthetic-aperture-imaging-phantom-and-in-vivo-evaluation
#13
Rohit Nayak, Giovanni Schifitto, Marvin M Doyley
PURPOSE: Vascular elastography can visualize the strain distribution in the carotid artery, which could be useful in assessing the propensity of advanced plaques to rupture. In our previous studies, we demonstrated that sparse synthetic aperture (SA) imaging can produce high quality vascular strain elastograms. However, the low output power of SA imaging may hamper its clinical utility. In this study, we hypothesize that multi-element defocused emissions can overcome this limitation and improve the quality of the vascular strain elastograms...
May 11, 2017: Medical Physics
https://www.readbyqxmd.com/read/28489536/dual-frequency-piezoelectric-endoscopic-transducer-for-imaging-vascular-invasion-in-pancreatic-cancer
#14
Brooks D Lindsey, Jinwook Kim, Paul A Dayton, Xiaoning Jiang
Cancers of the pancreas have the poorest prognosis among all cancers, as many tumors are not detected until surgery is no longer a viable option. Surgical viability is typically determined via endoscopic ultrasound imaging. However, many patients who may be eligible for resection are not offered surgery due to diagnostic challenges in determining vascular or lymphatic invasion. In this article, we describe the development of a dual-frequency piezoelectric transducer for rotational endoscopic imaging designed to transmit at 4 MHz and receive at 20 MHz in order to image microbubble-specific superharmonic signals...
May 8, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28475050/development-of-a-mechanical-scanning-device-with-high-frequency-ultrasound-transducer-for-ultrasonic-capsule-endoscopy
#15
Xingying Wang, Vipin Seetohul, Ruimin Chen, Ming Qian, Congzhi Wang, Zhihong Huang, Qifa Zhou, Hairong Zheng, Sandy Cochran, Weibao Qiu
Wireless capsule endoscopy has opened a new era by enabling remote diagnostic assessment of the gastrointestinal (GI) tract in a painless procedure. Video capsule endoscopy (VCE) is currently commercially available worldwide. However, it is limited to visualization of superficial tissue. Ultrasound (US) imaging is a complementary solution as it is capable of acquiring transmural information from the tissue wall. This paper presents a mechanical scanning device incorporating a high-frequency transducer specifically as a proof of concept for ultrasound capsule endoscopy (USCE), providing information that may usefully assist future research...
May 2, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28471755/a-finite-element-model-to-study-the-effect-of-tissue-anisotropy-on-ex-vivo-arterial-shear-wave-elastography-measurements
#16
Darya Alexandrovna Shcherbakova, Nic Debusschere, Annette Caenen, Francesco Iannaccone, Mathieu Pernot, Abigail Swillens, Patrick Segers
Shear wave elastography (SWE) is an ultrasound (US) diagnostic method for measuring the stiffness of soft tissues based on generated shear waves (SWs). SWE has been applied to bulk tissues, but in arteries it is still under investigation. Previously performed studies in arteries or arterial phantoms demonstrated the potential of SWE to measure arterial wall stiffness - a relevant marker in prediction of cardiovascular diseases. This study is focused on numerical modelling of SWs in ex vivo equine aortic tissue, yet based on experimental SWE measurements with the tissue dynamically loaded while rotating the US probe to investigate the sensitivity of SWE to the anisotropic structure...
May 4, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28469205/real-time-intravascular-photoacoustic-ultrasound-imaging-of-lipid-laden-plaque-in-human-coronary-artery-at-16-frames-per-second
#17
Jie Hui, Yingchun Cao, Yi Zhang, Ayeeshik Kole, Pu Wang, Guangli Yu, Gregory Eakins, Michael Sturek, Weibiao Chen, Ji-Xin Cheng
Intravascular photoacoustic-ultrasound (IVPA-US) imaging is an emerging hybrid modality for the detection of lipid-laden plaques, as it provides simultaneous morphological and lipid-specific chemical information of an artery wall. Real-time imaging and display at video-rate speed are critical for clinical utility of the IVPA-US imaging technology. Here, we demonstrate a portable IVPA-US system capable of imaging at up to 25 frames per second in real-time display mode. This unprecedented imaging speed was achieved by concurrent innovations in excitation laser source, rotary joint assembly, 1 mm IVPA-US catheter size, differentiated A-line strategy, and real-time image processing and display algorithms...
May 3, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28462719/intraoperative-localisation-of-impalpable-breast-lesions-utilising-the-rollis-technique-following-peritumoral-99mtc-colloid-sentinel-node-lymphoscintigraphy
#18
Te-Jui Hung, John Burrage, Anita Bourke, Donna Taylor
BACKGROUND: Ultrasound or stereotactic guided hook-wire localisation has been the standard-of-care for the pre-surgical localisation of impalpable breast lesions, which account for approximately a third of all breast cancer. Radioguided occult lesion localisation using I-125 seeds (ROLLIS) is a relatively new technique for guiding surgical excision of impalpable breast lesions, and is a promising alternative to the traditional hook-wire method. When combined with Tc-99m labelled colloid for sentinel node mapping in clinically indicated cases, there has been uncertainty regarding whether the downscatter of Tc-99m into the I-125 energy spectrum could adversely affect the intra-operative detection of the I-125 seed, especially pertaining to a peritumoral injection...
April 27, 2017: Current Radiopharmaceuticals
https://www.readbyqxmd.com/read/28459681/multi-access-in-vivo-biotelemetry-using-sonomicrometry-and-m-scan-ultrasound-imaging
#19
Sri Harsha Kondapalli, Yarub Alazzawi, Marcin Malinowski, Tomasz Timek, Shantanu Chakrabartty
OBJECTIVE: In this paper we investigate the use of commercial off-the-shelf (COTS) diagnostic ultrasound readers to achieve multi-access wireless in-vivo telemetry with millimetersized sonomicrometry crystal transducers. METHODS: The sonomicrometry crystals generate ultrasonic pulses that supersede the echoes generated at the tissue interfaces in response to Mscan interrogation pulses. The traces of these synthetic pulses are captured on an M-scan image and the transmitted data is decoded using image deconvolution and de-blurring algorithms...
April 25, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28458062/experimental-performance-assessment-of-the-sub-band-minimum-variance-beamformer-for-ultrasound-imaging
#20
Konstantinos Diamantis, Alan Greenaway, Tom Anderson, Jørgen Arendt Jensen, Vassilis Sboros
Recent progress in adaptive beamforming techniques for medical ultrasound has shown that current resolution limits can be surpassed. One method of obtaining improved lateral resolution is the Minimum Variance (MV) beamformer. The frequency domain implementation of this method effectively divides the broadband ultrasound signals into sub-bands (MVS) to conform with the narrow-band assumption of the original MV theory. This approach is investigated here using experimental Synthetic Aperture (SA) data from wire and cyst phantoms...
April 21, 2017: Ultrasonics
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"