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Hashemi HS, Mohammed SK, Zeng Q, Azar RZ, Rohling RN, Salcudean SE. 3-D Ultrafast Shear Wave Absolute Vibro-Elastography Using a Matrix Array Transducer. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:1039-1053. [PMID: 37235463 DOI: 10.1109/tuffc.2023.3280450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Real-time ultrasound imaging plays an important role in ultrasound-guided interventions. The 3-D imaging provides more spatial information compared to conventional 2-D frames by considering the volumes of data. One of the main bottlenecks of 3-D imaging is the long data acquisition time, which reduces practicality and can introduce artifacts from unwanted patient or sonographer motion. This article introduces the first shear wave absolute vibro-elastography (S-WAVE) method with real-time volumetric acquisition using a matrix array transducer. In S-WAVE, an external vibration source generates mechanical vibrations inside the tissue. The tissue motion is then estimated and used in solving a wave equation inverse problem to provide the tissue elasticity. A matrix array transducer is used with a Verasonics ultrasound machine and a frame rate of 2000 volumes/s to acquire 100 radio frequency (RF) volumes in 0.05 s. Using plane wave (PW) and compounded diverging wave (CDW) imaging methods, we estimate axial, lateral, and elevational displacements over 3-D volumes. The curl of the displacements is used with local frequency estimation to estimate elasticity in the acquired volumes. Ultrafast acquisition extends substantially the possible S-WAVE excitation frequency range, now up to 800 Hz, enabling new tissue modeling and characterization. The method was validated on three homogeneous liver fibrosis phantoms and on four different inclusions within a heterogeneous phantom. The homogeneous phantom results show less than 8% (PW) and 5% (CDW) difference between the manufacturer values and the corresponding estimated values over a frequency range of 80-800 Hz. The estimated elasticity values for the heterogeneous phantom at 400-Hz excitation frequency show the average errors of 9% (PW) and 6% (CDW) compared to the provided average values by magnetic resonance elastography (MRE). Furthermore, both imaging methods were able to detect the inclusions within the elasticity volumes. An ex vivo study on a bovine liver sample shows less than 11% (PW) and 9% (CDW) difference between the estimated elasticity ranges by the proposed method and the elasticity ranges provided by MRE and acoustic radiation force impulse (ARFI).
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Baek J, Basavarajappa L, Hoyt K, Parker KJ. Disease-Specific Imaging Utilizing Support Vector Machine Classification of H-Scan Parameters: Assessment of Steatosis in a Rat Model. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:720-731. [PMID: 34936555 PMCID: PMC8908945 DOI: 10.1109/tuffc.2021.3137644] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In medical imaging, quantitative measurements have shown promise in identifying diseases by classifying normal versus pathological parameters from tissues. The support vector machine (SVM) has shown promise as a supervised classification algorithm and has been widely used. However, the classification results typically identify a category of abnormal tissues but do not necessarily differentiate progressive stages of a disease. Moreover, the classification result is typically provided independently as a supplement to medical images, which contributes to an overload of information sources in the clinic. Hence, we propose a new imaging method utilizing the SVM to integrate classification results into medical images. This framework is called disease-specific imaging (DSI) that produces a color overlaid highlight on B-mode ultrasound images indicating the type, location, and severity of pathology from different conditions. In this article, the SVM training was performed to construct hyperplanes that can differentiate normal, fibrosis, steatosis, and pancreatic ductal adenocarcinoma (PDAC) metastases in livers based on ultrasound echoes. Also, cluster centroids for specific diseases define unique disease axes, and the inner product between measured features and any disease axis selected by the SVM quantifies the disease progression. The features were measured from 2794 ultrasound frames using the H-scan analysis, attenuation estimation, and B-mode image analysis. The performance of our proposed DSI method was evaluated for a preclinical model of steatosis ( n = 400 frames). The contribution of each feature was assessed, and the results were compared with ground truth from histology. Moreover, the images generated by our DSI were compared with earlier imaging methods of B-mode, H-scan, and histology. The comparisons demonstrate that DSI images yield higher sensitivity to monitor progressive steatosis than B-mode and H-scan and provide a comparable performance with the histology. For the parameter comparison, DSI and H-scan resulted in similar correlation with histology ( rs = 0.83 ) but higher than attenuation ( rs = 0.73 ) and B-mode ( rs = 0.47 ). Therefore, we conclude that DSI utilizing the SVM applied to steatosis can visually represent the classification results with color highlighting, which can simplify the interpretation of classification compared to the traditional SVM result. We expect that the proposed DSI can be used for any medical imaging modality that can estimate multiple quantitative parameters at high resolution.
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Kaliaev A, Chavez W, Soto J, Huda F, Xie H, Nguyen M, Shamdasani V, Anderson S. Quantitative Ultrasound Assessment of Hepatic Steatosis. J Clin Exp Hepatol 2022; 12:1091-1101. [PMID: 35814521 PMCID: PMC9257875 DOI: 10.1016/j.jceh.2022.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 01/17/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND/AIMS Non-alcoholic fatty liver disease (NAFLD) is widespread chronic disease of the live in humans with the prevalence of 30% of the United States population.1,2 The goal of the study is to validate the performance of quantitative ultrasound algorithms in the assessment of hepatic steatosis in patients with suspected NAFLD. METHODS This prospective study enrolled a total of 31 patients with clinical suspicion of NAFLD to receive liver fat measurements by quantitative ultrasound and reference MRI measurements (proton density fat-fraction, PDFF). The following ultrasound (US) parameters based on both raw ultrasound RF (Radio Frequency) data and 2D B-mode images of the liver were analyzed with subsequent correlation with MRI-PDFF: hepatorenal index, acoustic attenuation coefficient, Nakagami coefficient parameter, shear wave viscosity, shear wave dispersion and shear wave elasticity. Ultrasound parameters were also correlated with the presence of hypertension and diabetes. RESULTS The mean (± SD) age and body mass index of the patients were 49.03 (± 12.49) and 30.12 (± 6.15), respectively. Of the aforementioned ultrasound parameters, the hepatorenal index and acoustic attenuation coefficient showed a strong correlation with MRI-PDFF derivations of hepatic steatosis, with r-values of 0.829 and 0.765, respectively. None of the remaining US parameters showed strong correlations with PDFF. Significant differences in Nakagami parameters and acoustic attenuation coefficients were found in those patients with and without hypertension. CONCLUSIONS Hepatorenal index and acoustic attenuation coefficient correlate well with MRI-PDFF-derived measurements of hepatic steatosis. Quantitative ultrasound is a promising tool for the diagnosis and assessment of patients with NAFLD.
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Key Words
- ALT, alanine aminotransferase
- AST, aspartate aminotransferase
- BMI, body mass index
- DICOM, digital imaging and communications in medicine
- HIPAA, health insurance portability and accountability act
- HRI, hepatorenal index
- Hgb A1C, hemoglobin A1C (glycated hemoglobin)
- IQ, in-phase quadrature
- IR, insulin resistance
- LDL, low-density lipoprotein
- MRI-PDFF, magnetic resonance imaging - proton density fat-fraction
- NAFLD, non-alcoholic fatty liver disease
- NASH, non-alcoholic steatohepatitis
- RF, raw radio frequency
- ROI, regions of interest
- SD, standard deviation
- T2DM, type 2 diabetes mellitus
- US, ultrasound
- liver fat quantification
- non-alcoholic fatty liver disease
- ultrasound
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Affiliation(s)
- Artem Kaliaev
- Boston University Medical Center, Department of Radiology, Boston, MA, USA,Address for correspondence: Artem Kaliaev, Department of Radiology, Boston University Medical Center, 820 Harrison Ave, Boston, MA 02118, USA.
| | - Wilson Chavez
- Boston University Medical Center, Department of Radiology, Boston, MA, USA
| | - Jorge Soto
- Boston University Medical Center, Department of Radiology, Boston, MA, USA
| | - Fahimul Huda
- Boston University Medical Center, Department of Radiology, Boston, MA, USA
| | - Hua Xie
- Ultrasound Imaging and Interventions, Philips Research North America, Cambridge, MA, USA
| | - Man Nguyen
- Ultrasound Imaging and Interventions, Philips Research North America, Cambridge, MA, USA
| | | | - Stephan Anderson
- Boston University Medical Center, Department of Radiology, Boston, MA, USA
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Pirmoazen AM, Khurana A, Loening AM, Liang T, Shamdasani V, Xie H, El Kaffas A, Kamaya A. Diagnostic Performance of 9 Quantitative Ultrasound Parameters for Detection and Classification of Hepatic Steatosis in Nonalcoholic Fatty Liver Disease. Invest Radiol 2022; 57:23-32. [PMID: 34049335 DOI: 10.1097/rli.0000000000000797] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is a leading cause of chronic liver disease worldwide. Quantitative ultrasound (QUS) parameters based on radiofrequency raw data show promise in quantifying liver fat. PURPOSE The aim of this study was to evaluate the diagnostic performance of 9 QUS parameters compared with magnetic resonance imaging (MRI)-estimated proton density fat fraction (PDFF) in detecting and staging hepatic steatosis in patients with or suspected of NAFLD. MATERIALS AND METHODS In this Health Insurance Portability and Accountability Act-compliant institutional review board-approved prospective study, 31 participants with or suspected of NAFLD, without other underlying chronic liver diseases (13 men, 18 women; average age, 52 years [range, 26-90 years]), were examined. The following parameters were obtained: acoustic attenuation coefficient (AC); hepatorenal index (HRI); Nakagami parameter; shear wave elastography measures such as shear wave elasticity, viscosity, and dispersion; and spectroscopy-derived parameters including spectral intercept (SI), spectral slope (SS), and midband fit (MBF). The diagnostic ability (area under the receiver operating characteristic curves and accuracy) of QUS parameters was assessed against different MRI-PDFF cutoffs (the reference standard): 6.4%, 17.4%, and 22.1%. Linearity with MRI-PDFF was evaluated with Spearman correlation coefficients (p). RESULTS The AC, SI, Nakagami, SS, HRI, and MBF strongly correlated with MRI-PDFF (P = 0.89, 0.89, 0.88, -0.87, 0.81, and 0.71, respectively [P < 0.01]), with highest area under the receiver operating characteristic curves (ranging from 0.85 to 1) for identifying hepatic steatosis using 6.4%, 17.4%, and 22.1% MRI-PDFF cutoffs. In contrast, shear wave elasticity, shear wave viscosity, and shear wave dispersion did not strongly correlate to MRI-PDFF (P = 0.45, 0.38, and 0.07, respectively) and had poor diagnostic performance. CONCLUSION The AC, Nakagami, SI, SS, MBF, and HRI best correlate with MRI-PDFF and show high diagnostic performance for detecting and classifying hepatic steatosis in our study population. SUMMARY STATEMENT Quantitative ultrasound is an accurate alternative to MRI-based techniques for evaluating hepatic steatosis in patients with or at risk of NAFLD. KEY FINDINGS Our preliminary results show that specific quantitative ultrasound parameters accurately detect different degrees of hepatic steatosis in NAFLD.
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Affiliation(s)
- Amir M Pirmoazen
- From the Department of Radiology, School of Medicine, Stanford University, California
| | - Aman Khurana
- Departments of Radiology and Biomedical Engineering, University of Kentucky, Lexington
| | - Andreas M Loening
- From the Department of Radiology, School of Medicine, Stanford University, California
| | - Tie Liang
- From the Department of Radiology, School of Medicine, Stanford University, California
| | - Vijay Shamdasani
- Strategy & Business Development, Philips Healthcare, Cambridge, Massachusetts
| | - Hua Xie
- Department of Precision Diagnosis and Image Guided Therapy, Philips Research North America, Cambridge, Massachusetts
| | - Ahmed El Kaffas
- Department of Radiology, Molecular Imaging Program at Stanford, School of Medicine, Stanford University, California
| | - Aya Kamaya
- From the Department of Radiology, School of Medicine, Stanford University, California
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Wood BG, Kijanka P, Liu HC, Urban MW. Evaluation of Robustness of Local Phase Velocity Imaging in Homogenous Tissue-Mimicking Phantoms. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:3514-3528. [PMID: 34456084 PMCID: PMC8578323 DOI: 10.1016/j.ultrasmedbio.2021.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/21/2021] [Accepted: 08/01/2021] [Indexed: 06/13/2023]
Abstract
Shear wave elastography (SWE) is a method of evaluating mechanical properties of soft tissues. Most current implementations of SWE report the group velocity for shear wave velocity, which assumes an elastic, isotropic, homogenous and incompressible tissue. Local phase velocity imaging (LPVI) is a novel method of phase velocity reconstruction that allows for accurate evaluation of shear wave velocity at specified frequencies. This method's robustness was evaluated in 11 elastic and 8 viscoelastic phantoms using linear and curvilinear arrays. We acquired data with acoustic radiation force push beams with different focal depths and F-numbers and reconstructed phase velocity images over a wide range of frequencies. Regardless of phantom, push beam focal depth and reconstruction frequency, an F-number around 3.0 was found to produce the largest usable area in the phase velocity reconstructions. For elastic phantoms scanned with a linear array, the optimal focal depth, frequency range and maximum region of interest (ROI) were 20-30 mm, 100-400 Hz and 2.70 cm2, respectively. For viscoelastic phantoms scanned with a linear array, the optimal focal depth, frequency and maximum ROI were 20-30 mm, 100-300 Hz and 1.54 cm2, respectively. For the curvilinear array in the same phantoms, optimal focal depth, frequency range and maximum ROIs were 45-60 mm, 100-400 and 100-300 Hz and 1.54 cm2, respectively. In further work, LPVI reconstructions from inclusion phantoms will be evaluated to simulate non-homogeneous tissues. Additionally, LPVI will be evaluated in larger-volume phantoms to account for wave reflection from the containers when using the curvilinear array.
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Affiliation(s)
- Benjamin G Wood
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Piotr Kijanka
- Department of Robotics and Mechatronics, AGH University of Science and Technology, Krakow, Poland
| | - Hsiao-Chuan Liu
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA
| | - Matthew W Urban
- Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
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Baek J, Poul SS, Basavarajappa L, Reddy S, Tai H, Hoyt K, Parker KJ. Clusters of Ultrasound Scattering Parameters for the Classification of Steatotic and Normal Livers. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:3014-3027. [PMID: 34315619 PMCID: PMC8445071 DOI: 10.1016/j.ultrasmedbio.2021.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 06/03/2021] [Accepted: 06/17/2021] [Indexed: 05/08/2023]
Abstract
The study of ultrasound tissue interactions in fatty livers has a long history with strong clinical potential for assessing steatosis. Recently we proposed alternative measures of first- and second-order statistics of echoes from soft tissues, namely, the H-scan, which is based on a matched filter approach, to quantify scattering transfer functions and the Burr distribution to model speckle patterns. Taken together, these approaches produce a multiparameter set that is directly related to the fundamentals of ultrasound propagation in tissue. To apply this approach to the problem of assessing steatotic livers, these analyses were applied to in vivo rat livers (N=21) under normal feeding conditions or after receiving a methionine- and choline-deficient diet that produces steatosis within a few weeks. Ultrasound data were acquired at baseline and again at weeks 2 and 6 before applying the H-scan and Burr analyses. Furthermore, a classification technique known as the support vector machine was then used to find clusters of the five parameters that are characteristic of the different steatotic liver conditions as confirmed by histologic processing of excised liver tissue samples. With the in vivo multiparametric ultrasound measurement approach and determination of clusters, steatotic can be discriminated from normal livers with 100% accuracy in a rat animal model.
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Affiliation(s)
- Jihye Baek
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA
| | - Sedigheh S Poul
- Department of Mechanical Engineering, University of Rochester, Rochester, New York, USA
| | - Lokesh Basavarajappa
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas, USA
| | - Shreya Reddy
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas, USA
| | - Haowei Tai
- Department of Electrical and Computer Engineering, University of Texas at Dallas, Richardson, Texas, USA
| | - Kenneth Hoyt
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas, USA; Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Kevin J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
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Bhatt M, Yazdani L, Destrempes F, Allard L, Nguyen BN, Tang A, Cloutier G. Multiparametric in vivo ultrasound shear wave viscoelastography on farm-raised fatty duck livers: human radiology imaging applied to food sciences. Poult Sci 2021; 100:100968. [PMID: 33607316 PMCID: PMC7900601 DOI: 10.1016/j.psj.2020.12.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/14/2020] [Accepted: 12/18/2020] [Indexed: 12/19/2022] Open
Abstract
Nine mulard ducks that were being raised for foie gras (steatosis) production went through in vivo shear wave (SW) elastography imaging of their liver during the force-feeding period to investigate changes in liver tissue characteristics. A total of 4 imaging sessions at an interval of 3 to 4 d were conducted at the farm on each animal. Three ducks were sacrificed at the second, third, and fourth imaging sessions for histopathology analysis of all animals at these time points. Six SW elastography parameters were evaluated: SW speed, SW attenuation, SW dispersion, Young's modulus, viscosity, and shear modulus. Shear waves of different frequencies propagate with different phase velocities. Thus, SW speed and other dependent parameters such as Young's modulus, viscosity, and shear modulus were computed at 2 frequencies: 75 and 202 Hz. Each parameter depicted a statistically significant trend along the force-feeding process (P-values between 0.001 and 0.0001). The fat fraction of the liver increased over the 12-day period of feeding. All parameters increased monotonically over time at 75 Hz, whereas modal relations were seen at 202 Hz. Shear wave dispersion measured between 75 and 202 Hz depicted a plateau from day 5. Based on this validation, proposed imaging methods are aimed to be used in the future on naturally fed ducks and geese.
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Affiliation(s)
- Manish Bhatt
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2X 0A9
| | - Ladan Yazdani
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2X 0A9; Institute of Biomedical Engineering, University of Montreal, Montréal, Québec, Canada H3C 3J7
| | - François Destrempes
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2X 0A9
| | - Louise Allard
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2X 0A9
| | - Bich N Nguyen
- Service of Pathology, University of Montreal Hospital (CHUM), Montréal, Québec, Canada H2X 0C1
| | - An Tang
- Institute of Biomedical Engineering, University of Montreal, Montréal, Québec, Canada H3C 3J7; Laboratory of Medical Image Analysis, CRCHUM, Montréal, Québec, Canada H2X 0A9; Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montréal, Québec, Canada H3T 1J4
| | - Guy Cloutier
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, Québec, Canada H2X 0A9; Institute of Biomedical Engineering, University of Montreal, Montréal, Québec, Canada H3C 3J7; Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montréal, Québec, Canada H3T 1J4.
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Kijanka P, Urban MW. Local Phase Velocity Based Imaging of Viscoelastic Phantoms and Tissues. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:389-405. [PMID: 31976887 PMCID: PMC7590236 DOI: 10.1109/tuffc.2020.2968147] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Assessment of soft tissue elasticity and viscosity is of interest in several clinical applications. In this study, we present the feasibility of the local phase velocity based imaging (LPVI) method to create images of phase velocity and viscoelastic parameters in viscoelastic tissue-mimicking materials and soft tissues. In viscoelastic materials, it is necessary to utilize wave-mode isolation using a narrow bandpass filter combined with a directional filter in order to robustly reconstruct phase velocity images with LPVI in viscoelastic media over a wide range of frequencies. A pair of sequential focused acoustic radiation force push beams, focused once on the left-hand side and once on the right-hand side of the probe, was used to produce broadband propagating shear waves. The local shear wave phase velocity is then recovered in the frequency domain for multiple frequencies, for both acquired data sets. Then, a 2-D shear wave velocity map is reconstructed by combining maps from two separate acquisitions. By testing the method on simulated data sets and performing in vitro phantom and in vivo liver tissue experiments, we show the ability of the proposed technique to generate shear wave phase velocity maps at various frequencies in viscoelastic materials. Moreover, a nonlinear least-squares problem is solved in order to locally estimate elasticity and viscosity parameters. The LPVI method with added directional and wavenumber filters can produce phase velocity images, which can be used to characterize the viscoelastic materials.
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9
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Liu HC, Kijanka P, Urban MW. Four-dimensional (4D) phase velocity optical coherence elastography in heterogeneous materials and biological tissue. BIOMEDICAL OPTICS EXPRESS 2020; 11:3795-3817. [PMID: 33014567 PMCID: PMC7510894 DOI: 10.1364/boe.394835] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/21/2020] [Accepted: 06/09/2020] [Indexed: 05/03/2023]
Abstract
The variations of mechanical properties in soft tissues are biomarkers used for clinical diagnosis and disease monitoring. Optical coherence elastography (OCE) has been extensively developed to investigate mechanical properties of various biological tissues. These methods are generally based on time-domain data and measure the time-of-flight of the localized shear wave propagations to estimate the group velocity. However, there is considerable information that can be obtained from examining the mechanical properties such as wave propagation velocities at different frequencies. Here we propose a method to evaluate phase velocity, wave velocity at various frequencies, in four-dimensional space (x, y, z, f), called 4D-OCE phase velocity. The method enables local estimates of the phase velocity of propagating mechanical waves in a medium. We acquired and analyzed data with this method from a homogeneous reference phantom, a heterogeneous phantom material with four different excitation cases, and ex vivo porcine kidney tissue. The 3D-OCE group velocity was also estimated to compare with 4D-OCE phase velocity. Moreover, we performed numerical simulation of wave propagations to illustrate the boundary behavior of the propagating waves. The proposed 4D-OCE phase velocity is capable of providing further information in OCE to better understand the spatial variation of mechanical properties of various biological tissues with respect to frequency.
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Affiliation(s)
- Hsiao-Chuan Liu
- Department of Radiology, Mayo Clinic, 200
First St SW, Rochester, MN 55905, USA
| | - Piotr Kijanka
- Department of Radiology, Mayo Clinic, 200
First St SW, Rochester, MN 55905, USA
- Department of Robotics and Mechatronics,
AGH University of Science and Technology, Al. Mickiewicza 30, Krakow
30-059, Poland
| | - Matthew W. Urban
- Department of Radiology, Mayo Clinic, 200
First St SW, Rochester, MN 55905, USA
- Department of Physiology and Biomedical
Engineering, Mayo Clinic, 200 First St SW, Rochester, MN 55905,
USA
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Gesnik M, Bhatt M, Roy Cardinal MH, Destrempes F, Allard L, Nguyen BN, Alquier T, Giroux JF, Tang A, Cloutier G. In vivo Ultrafast Quantitative Ultrasound and Shear Wave Elastography Imaging on Farm-Raised Duck Livers during Force Feeding. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:1715-1726. [PMID: 32381381 DOI: 10.1016/j.ultrasmedbio.2020.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/05/2020] [Accepted: 03/10/2020] [Indexed: 06/11/2023]
Abstract
Shear wave elastography (speed and dispersion), local attenuation coefficient slope and homodyned-K parametric imaging were used for liver steatosis grading. These ultrasound biomarkers rely on physical interactions between shear and compression waves with tissues at both macroscopic and microscopic scales. These techniques were applied in a context not yet studied with ultrasound imaging, that is, monitoring steatosis of force-fed duck livers from pre-force-fed to foie gras stages. Each estimated feature presented a statistically significant trend along the feeding process (p values <10-3). However, whereas a monotonic increase in the shear wave speed was observed along the process, most quantitative ultrasound features exhibited an absolute maximum value halfway through the process. As the liver fat fraction in foie gras is much higher than that seen clinically, we hypothesized that a change in the ultrasound scattering regime is encountered for high-fat fractions, and consequently, care has to be taken when applying ultrasound biomarkers to grading of severe states of steatosis.
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Affiliation(s)
- Marc Gesnik
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Manish Bhatt
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Marie-Hélène Roy Cardinal
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - François Destrempes
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Louise Allard
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada
| | - Bich N Nguyen
- Service of Pathology, University of Montreal Hospital (CHUM), Montréal, QC, Canada
| | - Thierry Alquier
- CRCHUM and Montreal Diabetes Research Center, Montréal, QC, Canada; Department of Medicine, University of Montreal, Montréal, QC, Canada
| | - Jean-François Giroux
- Department of Biological Sciences, University of Quebec in Montreal, Montréal, QC, Canada
| | - An Tang
- Service of Radiology, University of Montreal Hospital (CHUM), Montréal, QC, Canada; Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montréal, QC, Canada; Laboratory of Medical Image Analysis, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada; Institute of Biomedical Engineering, University of Montreal, Montréal, QC, Canada
| | - Guy Cloutier
- Laboratory of Biorheology and Medical Ultrasonics, University of Montreal Hospital Research Center (CRCHUM), Montréal, QC, Canada; Department of Radiology, Radio-Oncology and Nuclear Medicine, University of Montreal, Montréal, QC, Canada; Institute of Biomedical Engineering, University of Montreal, Montréal, QC, Canada.
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Suzuki H, Kawashima H, Ohno E, Ishikawa T, Hashimoto S, Nakamura M, Miyahara R, Ishigami M, Hirooka Y, Fujishiro M. What is the role of measuring shear wave dispersion using shear wave elastography in pancreatic parenchyma? J Med Ultrason (2001) 2020; 47:575-581. [PMID: 32602019 DOI: 10.1007/s10396-020-01033-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/23/2020] [Indexed: 12/17/2022]
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12
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Ko A, Lee ES, Park HJ, Park SB, Kim HS, Choi BI. Added value of 2D shear wave imaging of the gallbladder bed of the liver for acute cholecystitis. Ultrasonography 2020; 39:384-393. [PMID: 32962334 PMCID: PMC7515659 DOI: 10.14366/usg.19060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 03/23/2020] [Indexed: 12/07/2022] Open
Abstract
Purpose The purpose of this study was to evaluate whether shear wave elastography (SWE) and the shear wave dispersion slope (SWD) obtained from 2-dimensional shear wave imaging (2D-SWI) of the gallbladder (GB) bed of the liver could be helpful in the diagnosis of acute cholecystitis. Methods We included 44 patients referred for abdominal ultrasonography (US) under the impression of acute cholecystitis from April 2018 to March 2019. Patients with chronic liver disease were excluded from this study. In addition to routine upper abdominal US, we performed 2D-SWI including liver stiffness measurements by SWE and SWD, which reflects tissue viscosity. 2D-SWI was performed at the GB bed of the liver through the right intercostal approach at least 3 times with different frames. We assessed typical US findings and the added value of 2D-SWI in diagnosing acute cholecystitis. Histopathologic results of surgical specimens were used as the standard of reference. If a surgical specimen was unavailable, a bile fluid test or clinical follow-up for more than 3 months served as the reference standard. Results The optimal cutoff values for SWE and SWD were 8 kPa and 10.9 (m/sec)/kHz, respectively. In the univariate analysis, SWE, GB distension, and sludge were predictive factors of acute cholecystitis. In the multivariate analysis, categorized SWE was the only significant predictor (P<0.01). By using 2D-SWI, the diagnostic performance of two readers did not significantly increase, although the inter-reader agreement improved (k=0.654-0.778). Conclusion 2D-SWI of the GB bed of the liver could be helpful for diagnosing acute cholecystitis.
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Affiliation(s)
- Ara Ko
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
| | - Eun Sun Lee
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
| | - Hyun Jeong Park
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
| | - Sung Bin Park
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
| | - Hee Sung Kim
- Department of Pathology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
| | - Byung Ihn Choi
- Department of Radiology, Chung-Ang University Hospital, Chung-Ang University College of Medicine, Seoul, Korea
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Luo X, Du L, Li Z. Ultrasound assessment of tensile stress in carotid arteries of healthy human subjects with varying age. BMC Med Imaging 2019; 19:93. [PMID: 31783804 PMCID: PMC6884773 DOI: 10.1186/s12880-019-0394-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 11/08/2019] [Indexed: 12/03/2022] Open
Abstract
Background Arterial remodeling is thought to reflect the adaptation of the vessel wall to mechanical and hemodynamic stimuli and contributes to the progression of cardiovascular and cerebrovascular diseases. Tensile stress (TS) is one of the mechanical properties of the artery wall. The purpose of this study was to investigate the tensile stress change (TS) of carotid artery with varying viscoelasticity in healthy subjects within two groups of different ages. Methods Forty-five subjects were recruited and randomly assigned into the group at the age above 50 years and below 50 years. The carotid arteries were examined by ultrasonography, using the techniques of shear wave elastography (SWE), shear wave dispersion (SWD) and radiofrequency (RF) -based ultrasound. The following values, including elastic modulus (SWER) and viscous index (SWDR), as well as the peak and mean TS of the left and right carotid arteries (L-PTS, R-PTS, L-MTS and R-MTS) were measured. The correlations between SWER, SWDR and tensile stress were evaluated. Results The SWER and SWDR of carotid arteries are lower in the subjects ≥50 years old than the subjects younger than 50 years (SWER, 10.29 ± 9.57 kPa VS 17.24 ± 14.07 kPa; SWDR, 11.99 ± 3.51 (m/s)/kHz VS 13.97 ± 3.71 (m/s)/kHz, P < 0.05). The R-PTS was lower in the group with younger age (P < 0.05). Pearson correlation analysis showed that SWER of carotid artery was positively correlated with the parameters of tensile stress, R-PTS, R-MTS, L-PTS and L-MTS(r = 0.218, r = 0.359, r = 0.209 and r = 0.369, respectively, P < 0.05). However, SWDR of carotid arteries was not significantly associated with TS. Conclusion Ultrasonic shear wave imaging could be used to quantitatively assess carotid viscoelasticity. The carotid TS was related to its elasticity while little related to its viscosity, suggesting that mechanical properties of the arterial wall might be better revealed. Trial registration Date of our trial registration: 2018-06-11. Registered with the official website of China Clinical Trial Registration Center (ChiCTR1800016590)
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Affiliation(s)
- Xianghong Luo
- Department of Echocardiography, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200080, China
| | - Lianfang Du
- Department of Ultrasound, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou District, Shanghai, 200080, China
| | - Zhaojun Li
- Department of Ultrasound, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, 100 Haining Road, Hongkou District, Shanghai, 200080, China.
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Ormachea J, Parker KJ, Barr RG. An initial study of complete 2D shear wave dispersion images using a reverberant shear wave field. ACTA ACUST UNITED AC 2019; 64:145009. [DOI: 10.1088/1361-6560/ab2778] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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15
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Sharma AK, Reis J, Oppenheimer DC, Rubens DJ, Ormachea J, Hah Z, Parker KJ. Attenuation of Shear Waves in Normal and Steatotic Livers. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:895-901. [PMID: 30685077 DOI: 10.1016/j.ultrasmedbio.2018.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/29/2018] [Accepted: 12/08/2018] [Indexed: 06/09/2023]
Abstract
Shear wave propagation in the liver has been a robust subject of research, with shear wave speed receiving the most attention. The correlation between increased shear wave speed and increased fibrosis in the liver has been established as a useful diagnostic tool. In comparison, the precise mechanisms of shear wave attenuation, and its relation to diseased states of the liver, are less well-established. This study focused on the hypothesis that steatosis adds a viscous (lossy) component to the liver, which increases shear wave attenuation. Twenty patients' livers were scanned with ultrasound and with induced shear wave propagation, and the resulting displacement profiles were analyzed using recently developed estimators to derive both the speed and attenuation of the shear waves within 6-cm2 regions of interest. The results were compared with pathology scores obtained from liver biopsies taken under ultrasound guidance. Across these cases, increases in shear wave attenuation were linked to increased steatosis score. This preliminary study supports the hypothesis and indicates the possible utility of the measurements for non-invasive and quantitative assessment of steatosis.
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Affiliation(s)
- Ashwani K Sharma
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, New York, USA
| | - Joseph Reis
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, New York, USA
| | - Daniel C Oppenheimer
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, New York, USA
| | - Deborah J Rubens
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, New York, USA
| | - Juvenal Ormachea
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA
| | | | - Kevin J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
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Xianghong LMD, Jianhui ZMD, Sihui SMD, Min YMD, Rong WMD, Lianfang DMD, Zhaojun LMD. The Role of Ultrasound Shear Wave Dispersion Imaging in Evaluating Carotid Viscoelasticity: A Preliminary Study. ADVANCED ULTRASOUND IN DIAGNOSIS AND THERAPY 2019. [DOI: 10.37015/audt.2019.190816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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17
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Ozturk A, Grajo JR, Gee MS, Benjamin A, Zubajlo RE, Thomenius KE, Anthony BW, Samir AE, Dhyani M. Quantitative Hepatic Fat Quantification in Non-alcoholic Fatty Liver Disease Using Ultrasound-Based Techniques: A Review of Literature and Their Diagnostic Performance. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:2461-2475. [PMID: 30232020 PMCID: PMC6628698 DOI: 10.1016/j.ultrasmedbio.2018.07.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 07/17/2018] [Accepted: 07/23/2018] [Indexed: 05/08/2023]
Abstract
Non-alcoholic fatty liver disease is a condition that is characterized by the presence of >5% fat in the liver and affects more than one billion people worldwide. If adequate and early precautions are not taken, non-alcoholic fatty liver disease can progress to cirrhosis and death. The current reference standard for detecting hepatic steatosis is a liver biopsy. However, because of the potential morbidity associated with liver biopsies, non-invasive imaging biomarkers have been extensively investigated. Magnetic resonance imaging-based methods have proven accuracy in quantifying liver steatosis; however, these techniques are costly and have limited availability. Ultrasound-based quantitative imaging techniques are increasingly utilized because of their widespread availability, ease of use and relative cost-effectiveness. Several ultrasound-based liver fat quantification techniques have been investigated, including techniques that measure changes in the acoustic properties of the liver caused by the presence of fat. In this review, we focus on quantitative ultrasound approaches and their diagnostic performance in the realm of non-alcoholic fatty liver disease.
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Affiliation(s)
- Arinc Ozturk
- Center for Ultrasound Research & Translation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Joseph R Grajo
- Division of Abdominal Imaging, Department of Radiology, University of Florida College of Medicine, Gainesville, Florida, USA
| | - Michael S Gee
- Division of Pediatric Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Alex Benjamin
- Device Realization and Computational Instrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Rebecca E Zubajlo
- Device Realization and Computational Instrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Kai E Thomenius
- Device Realization and Computational Instrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Brian W Anthony
- Device Realization and Computational Instrumentation Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Anthony E Samir
- Center for Ultrasound Research & Translation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Manish Dhyani
- Center for Ultrasound Research & Translation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA; (¶) Department of Radiology, Lahey Hospital & Medical Center, Burlington, Massachusetts, USA.
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18
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Parker KJ, Ormachea J, Drage MG, Kim H, Hah Z. The biomechanics of simple steatosis and steatohepatitis. ACTA ACUST UNITED AC 2018; 63:105013. [DOI: 10.1088/1361-6560/aac09a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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19
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Ormachea J, Lavarello RJ, McAleavey SA, Parker KJ, Castaneda B. Shear Wave Speed Measurements Using Crawling Wave Sonoelastography and Single Tracking Location Shear Wave Elasticity Imaging for Tissue Characterization. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2016; 63:1351-1360. [PMID: 27295662 DOI: 10.1109/tuffc.2016.2576962] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Elastography provides tissue stiffness information that attempts to characterize the elastic properties of tissue. However, there is still limited literature comparing elastographic modalities for tissue characterization. This study focuses on two quantitative techniques using different vibration sources that have not been compared to date: crawling wave sonoelastography (CWS) and single tracking location shear wave elasticity imaging (STL-SWEI). To understand each technique's performance, shear wave speed (SWS) was measured in homogeneous phantoms and ex vivo beef liver tissue. Then, the contrast, contrast-to-noise ratio (CNR), and lateral resolution were measured in an inclusion and two-layer phantoms. The SWS values obtained with both modalities were validated with mechanical measurements (MM) which serve as ground truth. The SWS results for the three different homogeneous phantoms (10%, 13%, and 16% gelatin concentrations) and ex vivo beef liver tissue showed good agreement between CWS, STL-SWEI, and MM as a function of frequency. For all gelatin phantoms, the maximum accuracy errors were 2.52% and 2.35% using CWS and STL-SWEI, respectively. For the ex vivo beef liver, the maximum accuracy errors were 9.40% and 7.93% using CWS and STL-SWEI, respectively. For lateral resolution, contrast, and CNR, both techniques obtained comparable measurements for vibration frequencies less than 300 Hz (CWS) and distances between the push beams ( ∆x ) between 3 mm and 5.31 mm (STL-SWEI). The results obtained in this study agree over an SWS range of 1-6 m/s. They are expected to agree in perfectly linear, homogeneous, and isotropic materials, but the SWS overlap is not guaranteed in all materials because each of the three methods have unique features.
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McAleavey SA, Parker KJ, Ormachea J, Wood RW, Stodgell CJ, Katzman PJ, Pressman EK, Miller RK. Shear Wave Elastography in the Living, Perfused, Post-Delivery Placenta. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:1282-1288. [PMID: 27006269 DOI: 10.1016/j.ultrasmedbio.2016.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 01/14/2016] [Accepted: 01/15/2016] [Indexed: 06/05/2023]
Abstract
The placenta is the critical interface between the mother and the developing fetus and is essential for survival and growth. Despite the widespread use of ultrasound imaging and Doppler in obstetrics and gynecology and the recent growth of elastographic technologies, little is known about the biomechanical (elastic shear wave) properties of the placenta and the range of normal and pathologic parameters that are present. This study uses a well-developed protocol for perfusing whole placentas, post-delivery, to maintain tissue integrity and function for hours. In this model, the placenta is living, whole and maintained within normal physiologic parameters such as flow, arterial pressure and oxygen, throughout examination by ultrasound, Doppler and shear wave elastography. The preliminary results indicate that normal placental tissue on the fetal side has shear wave speeds on the order of 2 m/s, in a range similar to those of animal livers. Some abnormalities are found outside this range, and thus, elastographic measures of the placenta may provide useful assessments related to the state of the tissue.
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Affiliation(s)
- Stephen A McAleavey
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, USA
| | - Kevin J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
| | - Juvenal Ormachea
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA
| | - Ronald W Wood
- Department of Obstetrics and Gynecology, University of Rochester Medical Center, Rochester, New York, USA
| | - Christopher J Stodgell
- Department of Obstetrics and Gynecology, University of Rochester Medical Center, Rochester, New York, USA
| | - Philip J Katzman
- Department of Pathology and Laboratory Medicine, University of Rochester Medical Center, Rochester, New York, USA
| | - Eva K Pressman
- Department of Obstetrics and Gynecology, University of Rochester Medical Center, Rochester, New York, USA
| | - Richard K Miller
- Department of Obstetrics and Gynecology, University of Rochester Medical Center, Rochester, New York, USA
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