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acoustic structure quantification

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
Yang Huang, Zhu Wang, Bing Liao, Jin-Yu Liang, Lu-Yao Zhou, Fen Wang, Wei Li, Jin-Ya Liu, Xiao-Yan Xie, Ming-De Lu, Guang-Jian Liu, Wei Wang
OBJECTIVES: To prospectively investigate the usefulness of acoustic structure quantification (ASQ) for noninvasive assessment of liver fibrosis in patients with chronic hepatitis B (CHB). METHODS: Consecutive patients with CHB scheduled for liver biopsy or partial liver resection underwent standardized ASQ examinations. The ASQ parameter, named focal disturbance (FD) ratio, were compared with METAVIR scores. The analysis was based on receiver operating characteristic (ROC) curves and multiple regression analysis...
July 2016: European Radiology
Jen-Li Looi, Andrew J Kerr, Ruvin Gabriel
Echocardiography is the principal non-invasive tool for initial evaluation and longitudinal monitoring of patients with significant valvular heart disease. However echocardiography can be limited by poor acoustic windows, and is dependent on the skill and experience of the sonographer. Cardiovascular magnetic resonance (CMR) can provide a comprehensive non-invasive assessment of valvular morphology, quantification of the severity of valvular dysfunction, determination of its aetiology, assessment of the consequences for the heart from the valve lesion including measurement of ventricular volumes and function, and evaluation of haemodynamic abnormalities...
November 2015: European Journal of Radiology
Jee-Young Son, Jae Young Lee, Nam-Joon Yi, Kwang-Woong Lee, Kyung-Suk Suh, Kwang Gi Kim, Jeong Min Lee, Joon Koo Han, Byung Ihn Choi
PURPOSE: To investigate the diagnostic performance of acoustic structure quantification (ASQ) for the assessment of hepatic steatosis by using hydrogen 1 ((1)H) magnetic resonance (MR) spectroscopy as the reference standard and to compare ASQ with hepatorenal ratio. MATERIALS AND METHODS: This prospective study was approved by an institutional review board, and informed written consent was obtained from all participants. ASQ and MR spectroscopy were performed in 89 participants (mean age, 41...
January 2016: Radiology
Yang Huang, Guang-Jian Liu, Bing Liao, Guang-Liang Huang, Jin-Yu Liang, Lu-Yao Zhou, Fen Wang, Wei Li, Xiao-Yan Xie, Wei Wang, Ming-De Lu
The aims of the present study are to assess the impact factors on acoustic structure quantification (ASQ) ultrasound and find the optimal parameter for the assessment of liver fibrosis. Twenty healthy volunteers underwent ASQ examinations to evaluate impact factors in ASQ image acquisition and analysis. An additional 113 patients with liver diseases underwent standardized ASQ examinations, and the results were compared with histologic staging of liver fibrosis. We found that the right liver displayed lower values of ASQ parameters than the left (p = 0...
September 2015: Ultrasound in Medicine & Biology
Thomas Karlas, Joachim Berger, Nikita Garnov, Franziska Lindner, Harald Busse, Nicolas Linder, Alexander Schaudinn, Bettina Relke, Rima Chakaroun, Michael Tröltzsch, Johannes Wiegand, Volker Keim
AIM: To compare ultrasound-based acoustic structure quantification (ASQ) with established non-invasive techniques for grading and staging fatty liver disease. METHODS: Type 2 diabetic patients at risk of non-alcoholic fatty liver disease (n = 50) and healthy volunteers (n = 20) were evaluated using laboratory analysis and anthropometric measurements, transient elastography (TE), controlled attenuation parameter (CAP), proton magnetic resonance spectroscopy ((1)H-MRS; only available for the diabetic cohort), and ASQ...
April 28, 2015: World Journal of Gastroenterology: WJG
Shahin Zandieh, Reinhard Bernt, Jochen Zwerina, Joerg Haller, Peter Knoll, Orang Seyeddain, Siroos Mirzaei
The aim of this study was to assess whether acoustic structure quantification (ASQ) can differentiate normal from pathological thyroid parenchyma in patients with diffuse autoimmune thyroid disease (AITD). We evaluated 83 subjects (72 [87%] women and 11 [13%] men) aged 19 to 94 years with a mean age of 53 years. We performed a prospective study (from March 2011 to November 2014) that included 43 (52%) patients with chronic autoimmune thyroiditis (CAT), 22 (26%) patients with Graves' disease (GD), and 18 (22%) healthy volunteers...
March 2016: Ultrasonic Imaging
David C Ferrier, Michael P Shaver, Philip J W Hands
This paper presents a review of micro- and nano-structure based oligonucleotide detection and quantification techniques. The characteristics of such devices make them very attractive for Point-of-Care or On-Site-Testing biosensing applications. Their small scale means that they can be robust and portable, their compatibility with modern CMOS electronics means that they can easily be incorporated into hand-held devices and their suitability for mass production means that, out of the different approaches to oligonucleotide detection, they are the most suitable for commercialisation...
June 15, 2015: Biosensors & Bioelectronics
Kevin N Rohmann, Eric Wersinger, Jeremy P Braude, Sonja J Pyott, Paul Albert Fuchs
Cholinergic neurons of the brainstem olivary complex project to and inhibit outer hair cells (OHCs), refining acoustic sensitivity of the mammalian cochlea. In all vertebrate hair cells studied to date, cholinergic inhibition results from the combined action of ionotropic acetylcholine receptors and associated calcium-activated potassium channels. Although inhibition was thought to involve exclusively small conductance (SK potassium channels), recent findings have shown that BK channels also contribute to inhibition in basal, high-frequency OHCs after the onset of hearing...
February 4, 2015: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Paulo G Coelho, Michael Sobieraj, Nick Tovar, Kenneth Andrews, Benjamin Paul, Nandini Govil, Seema Jeswani, Milan R Amin, Malvin N Janal, Ryan C Branski
The human vocal fold is a complex structure made up of distinct layers that vary in cellular and extracellular matrix composition. Elucidating the mechanical properties of vocal fold tissues is critical for the study of both acoustics and biomechanics of voice production, and essential in the context of vocal fold injury and repair. Both quasistatic and dynamic behavior in the 10-300 Hz range was explored in this preliminary investigation. The resultant properties of the lamina propria were compared to that of the nearby thyroarytenoid muscle...
December 2014: Materials Science & Engineering. C, Materials for Biological Applications
Ken ichiro Yamamura, Yasuo Takatsu, Tosiaki Miyati, Tetsuya Kimura
Functional magnetic resonance imaging (fMRI) has made a major contribution to the understanding of higher brain function, but fMRI with auditory stimulation, used in the planning of brain tumor surgery, is often inaccurate because there is a risk that the sounds used in the trial may not be correctly transmitted to the subjects due to acoustic noise. This prompted us to devise a method of digitizing sound transmission ability from the accuracy rate of 67 syllables, classified into three types. We evaluated this with and without acoustic noise during imaging...
October 2014: Nihon Hoshasen Gijutsu Gakkai Zasshi
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