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acoustic structure quantification

Jianxue Liu, Wei Ren, Hong Ai, Guoliang Dun, Yonghao Ji, Yaoren Zhang, Qinyun Wan, Shumei Lin
This study was conducted to evaluate the value of acoustic structure quantification (ASQ) technology versus that of point shear wave speed measurement (PSWSM) imaging technology for the assessment of liver fibrosis stage. A total of 104 patients with chronic hepatitis B (CHB) and 30 healthy control patients underwent ASQ and PSWSM examinations. Seven quantitative parameters were obtained from ASQ, and a principal component analysis was used to establish the integrative indicators. A quantitative parameter, known as the shear wave speed (SWS, m/s), was obtained from the PSWSM...
March 30, 2018: Ultrasound in Medicine & Biology
T Kobayashi, M Sasaki, T Ido, K Kamiya, Y Miura, Y Nagashima, K Ida, S Inagaki, A Fujisawa, S-I Itoh, K Itoh
We investigate spatial structures of turbulence and turbulent transport modulated by the geodesic acoustic mode (GAM), from which the excitation mechanism of the GAM is discussed. The GAM is found to be predominantly excited through a localized Reynolds stress force, rather than the dynamic shearing force. The evaluated growth rate is larger than the linear damping coefficients and is on the same order of magnitude as the effective growth rate evaluated from time evolution in the GAM kinetic energy.
January 26, 2018: Physical Review Letters
Zeng-Hui Qian, Xu Feng, Yang Li, Ke Tang
OBJECTIVE: Surgical operation within the region of the jugular foramen presents a great challenge. The authors characterized the quantitative impact of surgical window parameters on the exposure of the jugular foramen via a trans-mastoidal approach. METHODS: Computed tomography and magnetic resonance imaging data were used to establish a 3-dimensional model of the jugular foramen region. The mastoidale, posterior edge of the mastoid, and the superior edge of the bony external acoustic meatus were selected as points a, b, and c...
January 19, 2018: Journal of Craniofacial Surgery
Hayato Shiba, Peter Keim, Takeshi Kawasaki
It has recently been revealed that long-wavelength fluctuation exists in two- dimensional (2D) glassy systems, having the same origin as that given by the Mermin- Wagner theorem for 2D crystalline solids. Here, extending our recent studies, we discuss the quantification of long-wavelength acoustic fluctuation of a lightly supercooled liquid. This fluctuation can be estimated by subtracting the mean-squared displacement (MSD) of particles relative to its cage, represented by the cage-relative MSD, from the original particle MSD...
January 18, 2018: Journal of Physics. Condensed Matter: An Institute of Physics Journal
Subir Patra, Sourav Banerjee
Material state awareness of composites using conventional Nondestructive Evaluation (NDE) method is limited by finding the size and the locations of the cracks and the delamination in a composite structure. To aid the progressive failure models using the slow growth criteria, the awareness of the precursor damage state and quantification of the degraded material properties is necessary, which is challenging using the current NDE methods. To quantify the material state, a new offline NDE method is reported herein...
December 18, 2017: Materials
Subir Patra, Sourav Banerjee
Detection of precursor damage followed by the quantification of the degraded material properties could lead to more accurate progressive failure models for composite materials. However, such information is not readily available. In composite materials, the precursor damages-for example matrix cracking, microcracks, voids, interlaminar pre-delamination crack joining matrix cracks, fiber micro-buckling, local fiber breakage, local debonding, etc.-are insensitive to the low-frequency ultrasonic guided-wave-based online nondestructive evaluation (NDE) or Structural Health Monitoring (SHM) (~100-~500 kHz) systems...
December 16, 2017: Materials
Florian Vogl, Benjamin Bernet, Daniele Bolognesi, William R Taylor
PURPOSE: Cortical porosity is a key characteristic governing the structural properties and mechanical behaviour of bone, and its quantification is therefore critical for understanding and monitoring the development of various bone pathologies such as osteoporosis. Axial transmission quantitative acoustics has shown to be a promising technique for assessing bone health in a fast, non-invasive, and radiation-free manner. One major hurdle in bringing this approach to clinical application is the entanglement of the effects of individual characteristics (e...
2017: PloS One
David Gaddes, William Brian Reeves, Srinivas Tadigadapa
In this work, we demonstrate the quantification of creatinine in human urine samples using a microcalorimetric sensing system. The calorimetric sensor is based on an array of microfabricated Y-cut quartz resonators. The piezoelectric quartz is etched down to a thickness of 10 μm and exhibits a bulk acoustic resonance of 166 MHz. The temperature sensitivity of this high-frequency quartz resonator is 14 600 Hz/K due to the high phenomenological sensitivity of quartz. Most importantly, the quartz sensors and the analyte fluidics are decoupled providing a significantly more robust calorimetric sensing system than directly contacted chip calorimeters...
June 23, 2017: ACS Sensors
Dong Ho Lee, Jae Young Lee, Kyung Bun Lee, Joon Koo Han
Purpose To determine factors that significantly affect the focal disturbance (FD) ratio calculated with an acoustic structure quantification (ASQ) technique in a dietary-induced fatty liver disease rat model and to assess the diagnostic performance of the FD ratio in the assessment of hepatic steatosis by using histopathologic examination as a standard of reference. Materials and Methods Twenty-eight male F344 rats were fed a methionine-choline-deficient diet with a variable duration (3.5 days [half week] or 1, 2, 3, 4, 5, or 6 weeks; four rats in each group)...
November 2017: Radiology
Juliana Serafim da Silveira, Matthew Smyke, Adam V Rich, Yingmin Liu, Ning Jin, Debbie Scandling, Jennifer A Dickerson, Carlos E Rochitte, Subha V Raman, Lee C Potter, Rizwan Ahmad, Orlando P Simonetti
BACKGROUND: Aortic stenosis (AS) is a common valvular disorder, and disease severity is currently assessed by transthoracic echocardiography (TTE). However, TTE results can be inconsistent in some patients, thus other diagnostic modalities such as cardiovascular magnetic resonance (CMR) are demanded. While traditional unidirectional phase-contrast CMR (1Dir PC-CMR) underestimates velocity if the imaging plane is misaligned to the flow direction, multi-directional acquisitions are expected to improve velocity measurement accuracy...
March 7, 2017: Journal of Cardiovascular Magnetic Resonance
Michael A Mastanduno, Sanjiv S Gambhir
Photoacoustic imaging (PAI) is emerging as a potentially powerful imaging tool with multiple applications. Image reconstruction for PAI has been relatively limited because of limited or no modeling of light delivery to deep tissues. This work demonstrates a numerical approach to quantitative photoacoustic image reconstruction that minimizes depth and spectrally derived artifacts. We present the first time-domain quantitative photoacoustic image reconstruction algorithm that models optical sources through acoustic data to create quantitative images of absorption coefficients...
October 1, 2016: Biomedical Optics Express
Po-Hsiang Tsui, Ming-Chih Ho, Dar-In Tai, Ying-Hsiu Lin, Chiao-Yin Wang, Hsiang-Yang Ma
Acoustic structure quantification (ASQ) is a recently developed technique widely used for detecting liver fibrosis. Ultrasound Nakagami parametric imaging based on the Nakagami distribution has been widely used to model echo amplitude distribution for tissue characterization. We explored the feasibility of using ultrasound Nakagami imaging as a model-based ASQ technique for assessing liver fibrosis. Standard ultrasound examinations were performed on 19 healthy volunteers and 91 patients with chronic hepatitis B and C (n = 110)...
2016: Scientific Reports
Sun Hye Jeong, Hyun Sook Hong, Eun Hye Lee
Acoustic structure quantification (ASQ) software was used to analyze statistical information on acquired echo signals, to determine the ability of ASQ to distinguish normal salivary glands of asymptomatic patients from glands of patients with radiation sialadenitis (RS) after radioactive iodine therapy. The ASQ values of 192 salivary glands were compared by multinomial logistic regression analysis, and receiver operating characteristic curves were constructed. Between-observer agreement was assessed by calculating the intra-class correlation coefficient...
November 2016: Ultrasound in Medicine & Biology
Mingqin Qian, Chang Su, Dianyu Jiang, Guoning Yu
OBJECTIVES: To determine the application value of combined transperineal sonography and Virtual Touch tissue quantification (Siemens Medical Solutions, Mountain View, CA) on acoustic radiation force impulse imaging as a scanning method for diagnosis of female bladder neck obstruction. METHODS: Transperineal sonography and Virtual Touch tissue quantification were combined to depict the bladder neck and observe its sonographic characteristics in 36 patients with female bladder neck obstruction and 30 healthy adults in a case-control study...
June 2016: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
Jisang Park, Hyun Sook Hong, Chul-Hee Kim, Eun Hye Lee, Sun Hye Jeong, A Leum Lee, Heon Lee
OBJECTIVE: The objective of this study was to evaluate the ability of acoustic structure quantification (ASQ) to diagnose thyroiditis. MATERIALS AND METHODS: The echogenicity of 439 thyroid lobes, as determined using ASQ, was quantified and analyzed retrospectively. Thyroiditis was categorized into five subgroups. The results were presented in a modified chi-square histogram as the mode, average, ratio, blue mode, and blue average. We determined the cutoff values of ASQ from ROC analysis to detect and differentiate thyroiditis from a normal thyroid gland...
March 2016: AJR. American Journal of Roentgenology
Héctor Estrada, Johannes Rebling, Jake Turner, Daniel Razansky
It has been well recognized that the presence of a skull imposes harsh restrictions on the use of ultrasound and optoacoustic techniques in the study, treatment and modulation of the brain function. We propose a rigorous modeling and experimental methodology for estimating the insertion loss and the elastic constants of the skull over a wide range of frequencies and incidence angles. A point-source-like excitation of ultrawideband acoustic radiation was induced via the absorption of nanosecond duration laser pulses by a 20 μm diameter microsphere...
March 7, 2016: Physics in Medicine and Biology
Tae-Hoon Nam, Beom Jin Park, Deuk Jae Sung, Min Ju Kim, Na Yeon Han, Ki Choon Sim, Jean H Lee, Sung Bum Cho
PURPOSE: The purpose of this study was to evaluate the diagnostic efficacy of acoustic structure quantification (ASQ) parameters [mode, average, and focal distribution (FD) ratio] in the staging of hepatic fibrosis in patients with chronic viral hepatitis and to compare it with transient elastography (TE) by using liver biopsy as reference standard. METHODS: We studied 62 patients with chronic viral hepatitis. Each patient underwent ASQ evaluation and liver biopsy; 54 of these patients received TE...
February 2016: Abdominal Radiology
Anna Maria Alexandrou, Timo Saarinen, Jan Kujala, Riitta Salmelin
Human utterances demonstrate temporal patterning, also referred to as rhythm. While simple oromotor behaviors (e.g., chewing) feature a salient periodical structure, conversational speech displays a time-varying quasi-rhythmic pattern. Quantification of periodicity in speech is challenging. Unimodal spectral approaches have highlighted rhythmic aspects of speech. However, speech is a complex multimodal phenomenon that arises from the interplay of articulatory, respiratory, and vocal systems. The present study addressed the question of whether a multimodal spectral approach, in the form of coherence analysis between electromyographic (EMG) and acoustic signals, would allow one to characterize rhythm in natural speech more efficiently than a unimodal analysis...
January 2016: Journal of the Acoustical Society of America
Jan Keller, Tanja Eva-Maria Kaltenbach, Mark Martin Haenle, Suemeyra Oeztuerk, Tilmann Graeter, Richard Andrew Mason, Thomas Seufferlein, Wolfgang Kratzer
BACKGROUND: Objective of the study was to evaluate the diagnostic value of novel ultrasonographic modalities in comparison with simultaneously performed liver biopsy. METHODS: The results of simultaneously performed examinations using Acoustic Structure Quantification (ASQ), Virtual Touch Imaging and Quantification (VTIQ) and Virtual Touch Tissue Quantification (VTTQ) were compared with the findings of liver biopsy in patients with a wide variety of diffuse hepatopathies (n = 51)...
December 3, 2015: BMC Medical Imaging
Sun Jung Rhee, Hyun Sook Hong, Chul-Hee Kim, Eun Hye Lee, Jang Gyu Cha, Sun Hye Jeong
OBJECTIVES: This study aimed to evaluate the usefulness of Acoustic Structure Quantification (ASQ; Toshiba Medical Systems Corporation, Nasushiobara, Japan) values in the diagnosis of Hashimoto thyroiditis using B-mode sonography and to identify a cutoff ASQ level that differentiates Hashimoto thyroiditis from normal thyroid tissue. METHODS: A total of 186 thyroid lobes with Hashimoto thyroiditis and normal thyroid glands underwent sonography with ASQ imaging. The quantitative results were reported in an echo amplitude analysis (Cm(2)) histogram with average, mode, ratio, standard deviation, blue mode, and blue average values...
December 2015: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
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