keyword
MENU ▼
Read by QxMD icon Read
search

high frequency ultrasound

keyword
https://www.readbyqxmd.com/read/28643891/direct-comparison-of-high-temporal-resolution-cine-mri-with-doppler-ultrasound-for-assessment-of-diastolic-dysfunction-in-mice
#1
Thomas A Roberts, Anthony N Price, Laurence H Jackson, Valerie Taylor, Anna L David, Mark F Lythgoe, Daniel J Stuckey
Diastolic dysfunction is a sensitive early indicator of heart failure and can provide additional data to conventional measures of systolic function. Transmitral Doppler ultrasound, which measures the one-dimensional flow of blood through the mitral valve, is currently the preferred method for the measurement of diastolic function, but the measurement of the left ventricular volume changes using high-temporal-resolution cinematic magnetic resonance imaging (CINE MRI) is an alternative approach which is emerging as a potentially more robust and user-independent technique...
June 23, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28643383/multiecho-pseudo-golden-angle-stack-of-stars-thermometry-with-high-spatial-and-temporal-resolution-using-k-space-weighted-image-contrast
#2
Bryant T Svedin, Allison Payne, Bradley D Bolster, Dennis L Parker
PURPOSE: Implement and evaluate a 3D MRI method to measure temperature changes with high spatial and temporal resolution and large field of view. METHODS: A multiecho pseudo-golden angle stack-of-stars (SOS) sequence with k-space weighted image contrast (KWIC) reconstruction was implemented to simultaneously measure multiple quantities, including temperature, initial signal magnitude M(0), transverse relaxation time ( T2*), and water/fat images. Respiration artifacts were corrected using self-navigation...
June 22, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28641910/dependence-of-boiling-histotripsy-treatment-efficiency-on-hifu-frequency-and-focal-pressure-levels
#3
Tatiana D Khokhlova, Yasser A Haider, Adam D Maxwell, Wayne Kreider, Michael R Bailey, Vera A Khokhlova
Boiling histotripsy (BH) is a high-intensity focused ultrasound (HIFU)-based method of mechanical tissue fractionation that utilizes millisecond-long bursts of HIFU shock waves to cause boiling at the focus in milliseconds. The subsequent interaction of the incoming shocks with the vapor bubble mechanically lyses surrounding tissue and cells. The acoustic parameter space for BH has been investigated previously and an inverse dependence between the HIFU frequency and the dimensions of a BH lesion has been observed...
June 19, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28641234/improved-boundary-segmentation-of-skin-lesions-in-high-frequency-3d-ultrasound
#4
B Sciolla, P Delachartre, L Cowell, T Dambry, B Guibert
In this article, we propose a segmentation algorithm for skin lesions in 3D high-frequency ultrasound images. The segmentation is done on melanoma and Basal-cell carcinoma tumors, the most common skin cancer types, and could be used for diagnosis and surgical excision planning in a clinical context. Compared with previously proposed algorithms, which tend to underestimate the size of the lesion, we propose two new boundary terms which provide significant improvements of the accuracy. The first is a probabilistic boundary expansion (PBE) term designed to broaden the segmented area at the boundaries, which uses the feature asymmetry criterion...
June 15, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28639746/acute-changes-in-histopathology-and-intravascular-imaging-after-catheter-based-renal-denervation-in-a-porcine-model
#5
Atsushi Sakaoka, Akiyuki Takami, Yuji Onimura, Hitomi Hagiwara, Hisako Terao, Fumiaki Kumagai, Kiyoshi Matsumura
OBJECTIVES: We first aimed to identify the histopathological changes occurring immediately after renal denervation (RDN) with radiofrequency energy, and then to assess the feasibility of determining procedural success using currently available clinical intravascular imaging techniques. BACKGROUND: Catheter-based RDN has been used as an alternative therapy for hypertension. However, no practical endpoint to determine procedural success during treatment has been established...
June 22, 2017: Catheterization and Cardiovascular Interventions
https://www.readbyqxmd.com/read/28638983/treatment-of-benign-thyroid-nodules-by-high-intensity-focused-ultrasound-hifu-at-different-acoustic-powers-a-study-on-in-silico-phantom
#6
Fabiano Bini, Pierpaolo Trimboli, Franco Marinozzi, Luca Giovanella
BACKGROUND: The non-surgical therapies of benign thyroid nodules are gaining momentum due to the possibility to reduce the nodule's volume and avoid surgery. As the last technique introduced, high intensity focused ultrasound allows the thermal tissue treatment by directing energy inside the targeted nodule with no invasive instruments. In the present study we applied the Food and Drug Administration high intensity focused ultrasound simulator to in-silico phantom to evaluate the effects obtained by different acoustic powers...
June 21, 2017: Endocrine
https://www.readbyqxmd.com/read/28636919/monitoring-quantitative-ultrasound-parameter-changes-in-a-cell-pellet-model-of-cell-starvation
#7
Lauren A Wirtzfeld, Elizabeth S L Berndl, Gregory J Czarnota, Michael C Kolios
Although it has previously been shown that the spectral analysis of ultrasound backscatter data is sensitive to the cellular changes caused by apoptosis, the sensitivity of spectral analysis to oncosis or ischemic cell death had not previously been studied. Whereas many anticancer treatments induce apoptosis, others induce cell starvation, or oncosis. HT-29 colon adenocarcinoma cells were formed into pellets and covered in phosphate-buffered saline at room temperature for 56 h. The pellets were imaged every 8 h with high-frequency (55 MHz) ultrasound and the raw radio-frequency data processed...
June 20, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28634789/detection-and-grading-of-prostate-cancer-using-temporal-enhanced-ultrasound-combining-deep-neural-networks-and-tissue-mimicking-simulations
#8
Shekoofeh Azizi, Sharareh Bayat, Pingkun Yan, Amir Tahmasebi, Guy Nir, Jin Tae Kwak, Sheng Xu, Storey Wilson, Kenneth A Iczkowski, M Scott Lucia, Larry Goldenberg, Septimiu E Salcudean, Peter A Pinto, Bradford Wood, Purang Abolmaesumi, Parvin Mousavi
PURPOSE  : Temporal Enhanced Ultrasound (TeUS) has been proposed as a new paradigm for tissue characterization based on a sequence of ultrasound radio frequency (RF) data. We previously used TeUS to successfully address the problem of prostate cancer detection in the fusion biopsies. METHODS  : In this paper, we use TeUS to address the problem of grading prostate cancer in a clinical study of 197 biopsy cores from 132 patients. Our method involves capturing high-level latent features of TeUS with a deep learning approach followed by distribution learning to cluster aggressive cancer in a biopsy core...
June 20, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28633824/ultrasound-assisted-extraction-of-polysaccharides-from-rhododendron-aganniphum-antioxidant-activity-and-rheological-properties
#9
Xiao Guo, Xiaofei Shang, Xuzheng Zhou, Baotang Zhao, Jiyu Zhang
In this study, we aimed to optimize the extraction of polysaccharides from the leaves of Rhododendron aganniphum and investigate its rheological properties and antioxidant activity. After optimizing the operating parameters using a Box-Behnken design (BBD), the results showed that the optimal ultrasound-assisted extraction conditions were as follows: extraction temperature, 55°C; liquid-solid ratio, 25:1; extraction time, 2.2h; and ultrasound treatment power, 200W. The optimized experimental yield of polysaccharides by ultrasound-assisted extraction (PUAE) was 9...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28633815/ultrasound-assisted-selective-catalytic-transfer-hydrogenation-of-soybean-oil-using-5-pd-c-as-catalyst-under-ambient-conditions-in-water
#10
Sonam V Sancheti, Parag R Gogate
Catalytic transfer hydrogenation (CTH) is an alternative approach that does not require the use of potentially dangerous hydrogen gas. Pd/C is the most favoured catalyst for the selective hydrogenation of soybean oil yielding lower extent of formation of stearic acid and trans-isomer, which have adverse health effects. The present work deals with intensification of catalytic transfer hydrogenation of soybean oil in the presence of 5wt.% Pd/C using ultrasound under ambient reaction conditions. The effect of important operating parameters such as ultrasound power, temperature, type of hydrogen donor, catalyst loading and donor concentration on the progress of reaction has been investigated...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28633809/extraction-of-olive-oil-assisted-by-high-frequency-ultrasound-standing-waves
#11
Pablo Juliano, Fabian Bainczyk, Piotr Swiergon, Made Ian Maheswara Supriyatna, Claudia Guillaume, Leandro Ravetti, Pablo Canamasas, Giancarlo Cravotto, Xin-Qing Xu
High-frequency ultrasound standing waves (megasonics) have been demonstrated to enhance oil separation in the palm oil process at an industrial level. This work investigated the application of megasonics in the olive oil process on laboratory and pilot scale levels. Sound pressure level and cavitational yield distribution were characterised with hydrophones and luminol to determine associated physical and sonochemical effects inside the reactor. The effect of water addition (0%, 15%, and 30%), megasonic power levels (0%, 50%, and 100%), and malaxation time (10min, 30min, and 50min) was evaluated using response surface methodology (RSM) in a 700g batch extraction process...
September 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28633741/high-frequency-ultrasound-features-in-a-case-of-gouty-panniculitis
#12
P Maldonado Cid, C Rubio Flores, I Prats Caelles, V M Leis Dosil, F Alfageme Roldán, P Richi Alberti, C Santonja Garriga, R M Díaz Díaz
Gouty panniculitis is caused by the deposition of urate crystals in the subcutaneous tissue, accompanied by a lobular panniculitis. It presents as subcutaneous nodules, most commonly located on the lower extremities. Being an unusual clinical presentation of gout, the sonographic findings of gouty panniculitis have been scarcely described in the literature. Our report describes the ultrasound features we found in a case of gouty panniculitis and the usefulness of this technique for diagnosis and monitoring of this disease...
June 15, 2017: Dermatology Online Journal
https://www.readbyqxmd.com/read/28632662/treatment-of-incomplete-jones-fractures-with-low-intensity-pulsed-ultrasound-lipus
#13
Tateishi Tomohiko, Tsuyoshi Nagase, Teruhiko Nakagawa, Tsuchiya Masamitsu
OBJECTIVE: Stress fractures of the proximal epiphysis of the fifth metatarsal bone (termed Jones fracture) frequently occur in both senior high-school-age and older contestant-level soccer players, and its incidence in Japanese soccer players is higher than that in European players. Surgery is most commonly indicated for a complete fracture, and about 3 months are required before the patient is able to return to the sport. We have performed a "Jones fracture screening" to reduce the incidence of these fractures...
July 2017: Journal of Orthopaedic Trauma
https://www.readbyqxmd.com/read/28626980/comparison-of-management-regimens-following-ultrasound-diagnosis-of-nontubal-ectopic-pregnancies-a-retrospective-cohort-study
#14
J Ramkrishna, G R Kan, K L Reidy, W C Ang, R Palma-Dias
OBJECTIVE: To review management options for nontubal ectopic pregnancies. DESIGN: Retrospective cohort study. SETTING: Tertiary hospital in Melbourne, Australia. POPULATION: A total of 100 nontubal pregnancies: 1 abdominal, 32 caesarean scar, 14 cervical, 41 cornual-interstitial, 12 ovarian. METHODS: Cases were classified according to ectopic site. Management categories were medical, surgical, combination or expectant...
June 19, 2017: BJOG: An International Journal of Obstetrics and Gynaecology
https://www.readbyqxmd.com/read/28624131/studying-arterial-stiffness-using-high-frequency-ultrasound-in-mice-with-alzheimer-disease
#15
Chin-Chia Huang, Hsiang-Fan Cheng, Ben-Peng Zhu, Pei-Yu Chen, Suet Theng Beh, Yu-Min Kuo, Chih-Chung Huang
Alzheimer disease (AD) is an irreversible, progressive brain disorder that causes slow loss of memory and thinking skills, normally leading to death in 3-9 y. The etiology of AD is not fully understood but is widely believed to be induced by the production and deposition of amyloid-β peptide in the brain. Recently, a correlation was discovered between amyloid-β deposition and atherosclerosis in the cerebral arteries of postmortem brains, indicating that amyloid-β promotes atherogenesis and that in turn atherosclerosis promotes brain amyloid-β accumulation...
June 14, 2017: Ultrasound in Medicine & Biology
https://www.readbyqxmd.com/read/28622670/adaptive-clutter-demodulation-for-non-contrast-ultrasound-perfusion-imaging
#16
Jaime Tierney, Crystal Coolbaugh, Theodore Towse, Brett Byram
Conventional Doppler ultrasound is useful for visualizing fast blood flow in large resolvable vessels. However, frame rate and tissue clutter caused by movement of the patient or sonographer make visualizing slow flow with ultrasound difficult. Patient and sonographer motion causes spectral broadening of the clutter signal, which limits ultrasound's sensitivity to velocities greater than 5-10mm/s for typical clinical imaging frequencies. To address this, we propose a clutter filtering technique that may increase the sensitivity of Doppler measurements to at least as low as 0...
June 13, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28622042/the-relationship-between-the-24-hour-fluctuations-in-schlemm-s-canal-and-intraocular-pressure-an-observational-study-using-high-frequency-ultrasound-biomicroscopy
#17
Mu Li, Yin Zhao, Xiaoqin Yan, Hong Zhang
PURPOSE: To assess 24-hour fluctuations in Schlemm's canal (SC) parameters (cross-sectional area, perimeter) and intraocular pressure (IOP) and the relationship between these fluctuations in healthy individuals. METHODS: SC and IOP were examined in 29 participants at 2:30, 5:30, 11:30, 17:30, and 23:30 within one day. The superior, inferior, nasal, and temporal SC quadrants were evaluated using 80-MHz ultrasound biomicroscopy. RESULTS: SC parameters and IOP fluctuated significantly within 24 hours (all P < 0...
June 16, 2017: Current Eye Research
https://www.readbyqxmd.com/read/28621699/diagnostic-value-of-single-source-dual-energy-spectral-computed-tomography-for-papillary-thyroid-microcarcinomas
#18
Lin Li, Yong Wang, De-Hong Luo, Yan-Feng Zhao, Meng Lin, Wei Guo, Lei Hu, Chun-Wu Zhou, Xin-Ming Zhao
BACKGROUND: Ultrasound (US) and computed tomography (CT) are common diagnostic imaging methods for detecting and diagnosing papillary thyroid microcarcinoma (PTMC). However, single-source dual-energy spectral computed tomography (spectral CT) reduces beam hardening artefacts and optimizes contrast, which may add value in detecting PTMC. OBJECTIVE: To investigate values of applying single-source dual-energy spectral CT for diagnosing PTMCs, in comparison with high frequency ultrasound and conventional polychromatic images...
June 10, 2017: Journal of X-ray Science and Technology
https://www.readbyqxmd.com/read/28615645/intravascular-forward-looking-ultrasound-transducers-for-microbubble-mediated-sonothrombolysis
#19
Jinwook Kim, Brooks D Lindsey, Wei-Yi Chang, Xuming Dai, Joseph M Stavas, Paul A Dayton, Xiaoning Jiang
Effective removal or dissolution of large blood clots remains a challenge in clinical treatment of acute thrombo-occlusive diseases. Here we report the development of an intravascular microbubble-mediated sonothrombolysis device for improving thrombolytic rate and thus minimizing the required dose of thrombolytic drugs. We hypothesize that a sub-megahertz, forward-looking ultrasound transducer with an integrated microbubble injection tube is more advantageous for efficient thrombolysis by enhancing cavitation-induced microstreaming than the conventional high-frequency, side-looking, catheter-mounted transducers...
June 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28612570/-the-value-of-high-frequency-color-doppler-ultrasonography-in-the-diagnosis-of-solid-skin-tumorsa-a-preliminary-study
#20
Lin Zhong, Yuan-Jiao Tang, Yu-Jia Yang, Li Qiu
OBJECTIVES: To explore the value of high frequency color doppler ultrasonography in differentiating benign and malignant skin solid tumors. METHODS: Clinical and ultrasonic data of cutaneous solid tumors confirmed by pathology in our hospital were collected. The differences in clinical and sonographic features between benign and malignant tumors were statistically analyzed. RESULTS: A total of 512 patients, involving 527 cases of skin solid tumors, were enrolled in this study...
January 2017: Sichuan da Xue Xue Bao. Yi Xue Ban, Journal of Sichuan University. Medical Science Edition
keyword
keyword
112617
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"