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1
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Kim GS, Moon HH, Lee HS, Jeong JS. Compound Acoustic Radiation Force Impulse Imaging of Bovine Eye by Using Phase-Inverted Ultrasound Transducer. SENSORS (BASEL, SWITZERLAND) 2024; 24:2700. [PMID: 38732804 PMCID: PMC11085659 DOI: 10.3390/s24092700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 05/13/2024]
Abstract
In general, it is difficult to visualize internal ocular structure and detect a lesion such as a cataract or glaucoma using the current ultrasound brightness-mode (B-mode) imaging. This is because the internal structure of the eye is rich in moisture, resulting in a lack of contrast between tissues in the B-mode image, and the penetration depth is low due to the attenuation of the ultrasound wave. In this study, the entire internal ocular structure of a bovine eye was visualized in an ex vivo environment using the compound acoustic radiation force impulse (CARFI) imaging scheme based on the phase-inverted ultrasound transducer (PIUT). In the proposed method, the aperture of the PIUT is divided into four sections, and the PIUT is driven by the out-of-phase input signal capable of generating split-focusing at the same time. Subsequently, the compound imaging technique was employed to increase signal-to-noise ratio (SNR) and to reduce displacement error. The experimental results demonstrated that the proposed technique could provide an acoustic radiation force impulse (ARFI) image of the bovine eye with a broader depth-of-field (DOF) and about 80% increased SNR compared to the conventional ARFI image obtained using the in-phase input signal. Therefore, the proposed technique can be one of the useful techniques capable of providing the image of the entire ocular structure to diagnose various eye diseases.
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Affiliation(s)
| | | | | | - Jong Seob Jeong
- Department of Biomedical Engineering, Dongguk University, Seoul 04620, Republic of Korea; (G.S.K.); (H.H.M.); (H.S.L.)
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2
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Liu Y, Zeng S, Xu R. Application of Multiple Ultrasonic Techniques in the Diagnosis of Prostate Cancer. Front Oncol 2022; 12:905087. [PMID: 35832558 PMCID: PMC9271763 DOI: 10.3389/fonc.2022.905087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/12/2022] [Indexed: 11/23/2022] Open
Abstract
Methods for diagnosing prostate cancer (PCa) are developing in the direction of imaging. Advanced ultrasound examination modes include micro-Doppler, computerized-transrectal ultrasound, elastography, contrast-enhanced ultrasound and microultrasound. When two or more of these modes are used in PCa diagnosis, the combined technique is called multiparameter ultrasound (mp-US). Mp-US provides complementary information to multiparameter magnetic resonance imaging (mp-MRI) for diagnosing PCa. At present, no study has attempted to combine the characteristics of different ultrasound modes with advanced classification systems similar to the PIRADS system in mpMRI for the diagnosis of PCa. As an imaging method, mp-US has great potential in the diagnosis of PCa.
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Affiliation(s)
- Yushan Liu
- Department of Ultrasound, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Shi Zeng
- Department of Ultrasound, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Ran Xu
- Department of Urology, The Second Xiangya Hospital of Central South University, Changsha, China
- *Correspondence: Ran Xu,
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3
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Tan H, Rossa C. Electrical Impedance Tomography for Robot-Aided Internal Radiation Therapy. Front Bioeng Biotechnol 2021; 9:698038. [PMID: 34235139 PMCID: PMC8256893 DOI: 10.3389/fbioe.2021.698038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/27/2021] [Indexed: 12/24/2022] Open
Abstract
High dose rate brachytherapy (HDR) is an internal based radiation treatment for prostate cancer. The treatment can deliver radiation to the site of dominant tumor growth within the prostate. Imaging methods to delineate the dominant tumor are imperative to ensure the maximum success of HDR. This paper investigates the feasibility of using electrical impedance tomography (EIT) as the main imaging modality during robot-aided internal radiation therapy. A procedure utilizing brachytherapy needles in order to perform EIT for the purpose of robot-aided prostate cancer imaging is proposed. It is known that cancerous tissue exhibits different conductivity than healthy tissue. Using this information, it is hypothesized that a conductivity map of the tissue can be used to locate and delineate cancerous nodules via EIT. Multiple experiments were conducted using eight brachytherapy needle electrodes. Observations indicate that the imaging procedure is able to observe differences in tissue conductivity in a setting that approximates transperineal HDR and confirm that brachytherapy needles can be used as electrodes for this purpose. The needles can access the tissue at a specific depth that traditional EIT surface electrodes cannot. The results indicate the feasibility of using brachytherapy needles for EIT for the purpose internal radiation therapy.
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Affiliation(s)
- Hao Tan
- Faculty of Engineering and Applied Science, Ontario Tech University, Oshawa, ON, Canada
| | - Carlos Rossa
- Faculty of Engineering and Applied Science, Ontario Tech University, Oshawa, ON, Canada
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Gomez A, Rus G, Saffari N. Wave Propagation in a Fractional Viscoelastic Tissue Model: Application to Transluminal Procedures. SENSORS (BASEL, SWITZERLAND) 2021; 21:2778. [PMID: 33920801 PMCID: PMC8071186 DOI: 10.3390/s21082778] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/07/2021] [Accepted: 04/13/2021] [Indexed: 12/27/2022]
Abstract
In this article, a wave propagation model is presented as the first step in the development of a new type of transluminal procedure for performing elastography. Elastography is a medical imaging modality for mapping the elastic properties of soft tissue. The wave propagation model is based on a Kelvin Voigt Fractional Derivative (KVFD) viscoelastic wave equation, and is numerically solved using a Finite Difference Time Domain (FDTD) method. Fractional rheological models, such as the KVFD, are particularly well suited to model the viscoelastic response of soft tissue in elastography. The transluminal procedure is based on the transmission and detection of shear waves through the luminal wall. Shear waves travelling through the tissue are perturbed after encountering areas of altered elasticity. These perturbations carry information of medical interest that can be extracted by solving the inverse problem. Scattering from prostate tumours is used as an example application to test the model. In silico results demonstrate that shear waves are satisfactorily transmitted through the luminal wall and that echoes, coming from reflected energy at the edges of an area of altered elasticity, which are feasibly detectable by using the transluminal approach. The model here presented provides a useful tool to establish the feasibility of transluminal procedures based on wave propagation and its interaction with the mechanical properties of the tissue outside the lumen.
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Affiliation(s)
- Antonio Gomez
- UCL Mechanical Engineering, University College London, London WC1E 7JE, UK;
- Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain
| | - Guillermo Rus
- Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain
- Structural Mechanics Department, University of Granada, 18071 Granada, Spain;
- Excellence Research Unit “ModelingNature” (MNat), University of Granada, 18071 Granada, Spain
| | - Nader Saffari
- UCL Mechanical Engineering, University College London, London WC1E 7JE, UK;
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5
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Emara DM, Naguib NN, Yehia M, El Shafei MM. Ultrasound elastography in characterization of prostatic lesions: correlation with histopathological findings. Br J Radiol 2020; 93:20200035. [PMID: 32142374 PMCID: PMC10993208 DOI: 10.1259/bjr.20200035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/26/2020] [Accepted: 03/03/2020] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Ultrasound elastography is increasingly used in the diagnosis of prostate cancer, however results are heterogeneous. We correlate in a large sample-size prospective study the accuracy of elastography, aiming to settle an accurate cut-off point for diagnosis and possibility of use as a screening tool. METHODS Prospective study that included 120 patients with mean age 59.5 ± 9.8 years, showing enlarged prostate by clinical examination with prostate-specific antigen >4 ng ml-1.The study was done using high frequency high resolution endorectal probe with real time tissue elastography.Grayscale ultrasound examination was done first with Doppler followed by elastography color-coded map and strain ratio measurement. Then, transrectal ultrasound-guided core biopsy was done from suspicious areas detected by elastography (totally or partly stiff by color-coded map or with relative increased strain ratio), besides standard six-quadrant core biopsy samples. RESULTS There was statistically significant difference (p < 0.001) regarding strain ratio in benign and malignant lesions. Strain ratio showed significant proportionate correlation with prostate-specific antigen level and Gleason pathological score, while no significant correlation noted with the age or the prostatic volume. A strain ratio with a cut-off value of 1.9 showed a sensitivity of 100%, specificity 93.8%, positive predictive value of 79.3%, negative predictive value 100 and 95% accuracy in differentiating between malignant and benign lesions. CONCLUSION Strain ratio improves the detection of prostatic cancer with high sensitivity (100%) and high negative predictive value (100%). ADVANCES IN KNOWLEDGE Different prostatic lesions are mostly similar in grayscale ultrasound.Imaging plays an important role in differentiation of prostatic nodules.Ultrasound elastography may play an important role in distinguishing benign from malignant nodules.
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Affiliation(s)
- Doaa M Emara
- Department of radiodiagnosis and intervention, faculty of
medicine, Alexandria university,
Alexandria, Egypt
| | | | - Mohamed Yehia
- Department of Urology, faculty of medicine, Alexandria
university, Alexandria,
Egypt
| | - Mohamed M. El Shafei
- Department of radiodiagnosis and intervention, faculty of
medicine, Alexandria university,
Alexandria, Egypt
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Johnson B, Campbell S, Campbell-Kyureghyan N. The differences in measured prostate material properties between probing and unconfined compression testing methods. Med Eng Phys 2020; 80:44-51. [PMID: 32381284 DOI: 10.1016/j.medengphy.2020.03.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 01/21/2020] [Accepted: 03/01/2020] [Indexed: 01/20/2023]
Abstract
Characterization of the mechanical properties of organs is important for determining their behavior under load and understanding and predicting their response. In order to appropriately understand behavior, including developing predictive models, the method used to measure the properties should match the application as different testing techniques can yield different results. One of the organs where little mechanical testing has been performed is the prostate. Therefore, the goal of this paper is to expand the knowledge of prostate gland mechanical behavior by using two different compressive testing methods under various loading rates. No differences were found between the elastic modulus measured using the compression and probing protocols for both human and porcine specimens. The elastic modulus ranged from 0.08 MPa at 1%/s to 0.24 MPa at 25%/s for human specimens and from 0.2 MPa at 1%/s to 0.4 MPa at 25%/s for porcine specimens. A strain rate dependency of the elastic modulus was observed for both testing methods. The dependency on strain rate started to saturate at higher rates and a material model was created to quantify this dependence as well as the stress-strain behavior. No strain rate dependency was observed for failure stress or failure strain. Overall, similar values of elastic modulus were found for both probing and compression protocols and the relationship developed between elastic modulus and strain rate could be implemented in models of the prostate gland to aid in understanding the response to dynamic loads.
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Affiliation(s)
- Blake Johnson
- Industrial and Manufacturing Engineering Department, College of Engineering and Applied Science, University of Wisconsin-Milwaukee, 3200N Cramer St., Milwaukee, WI 53211, United States
| | - Scott Campbell
- Structural Analysis Consulting Group, PO Box 170735, Milwaukee, WI 53217, United States
| | - Naira Campbell-Kyureghyan
- Industrial and Manufacturing Engineering Department, College of Engineering and Applied Science, University of Wisconsin-Milwaukee, 3200N Cramer St., Milwaukee, WI 53211, United States; Department of Mechanical Engineering, School of Science and Engineering, Merrimack College, 315 Turnpike St., N Andover, MA 01845, United States.
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Rus G, Faris IH, Torres J, Callejas A, Melchor J. Why Are Viscosity and Nonlinearity Bound to Make an Impact in Clinical Elastographic Diagnosis? SENSORS (BASEL, SWITZERLAND) 2020; 20:E2379. [PMID: 32331295 PMCID: PMC7219338 DOI: 10.3390/s20082379] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 12/24/2022]
Abstract
The adoption of multiscale approaches by the biomechanical community has caused a major improvement in quality in the mechanical characterization of soft tissues. The recent developments in elastography techniques are enabling in vivo and non-invasive quantification of tissues' mechanical properties. Elastic changes in a tissue are associated with a broad spectrum of pathologies, which stems from the tissue microstructure, histology and biochemistry. This knowledge is combined with research evidence to provide a powerful diagnostic range of highly prevalent pathologies, from birth and labor disorders (prematurity, induction failures, etc.), to solid tumors (e.g., prostate, cervix, breast, melanoma) and liver fibrosis, just to name a few. This review aims to elucidate the potential of viscous and nonlinear elastic parameters as conceivable diagnostic mechanical biomarkers. First, by providing an insight into the classic role of soft tissue microstructure in linear elasticity; secondly, by understanding how viscosity and nonlinearity could enhance the current diagnosis in elastography; and finally, by compounding preliminary investigations of those elastography parameters within different technologies. In conclusion, evidence of the diagnostic capability of elastic parameters beyond linear stiffness is gaining momentum as a result of the technological and imaging developments in the field of biomechanics.
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Affiliation(s)
- Guillermo Rus
- Ultrasonics Group (TEP-959), Department of Structural Mechanics, University of Granada, 18071 Granada, Spain; (G.R.); (I.H.F.); (A.C.)
- Biomechanics Group (TEC-12), Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain;
- Excellence Research Unit “ModelingNature” MNat UCE.PP2017.03, University of Granada, 18071 Granada, Spain
| | - Inas H. Faris
- Ultrasonics Group (TEP-959), Department of Structural Mechanics, University of Granada, 18071 Granada, Spain; (G.R.); (I.H.F.); (A.C.)
- Biomechanics Group (TEC-12), Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain;
| | - Jorge Torres
- Ultrasonics Group (TEP-959), Department of Structural Mechanics, University of Granada, 18071 Granada, Spain; (G.R.); (I.H.F.); (A.C.)
- Biomechanics Group (TEC-12), Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain;
| | - Antonio Callejas
- Ultrasonics Group (TEP-959), Department of Structural Mechanics, University of Granada, 18071 Granada, Spain; (G.R.); (I.H.F.); (A.C.)
- Biomechanics Group (TEC-12), Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain;
| | - Juan Melchor
- Biomechanics Group (TEC-12), Instituto de Investigación Biosanitaria, ibs.GRANADA, 18012 Granada, Spain;
- Excellence Research Unit “ModelingNature” MNat UCE.PP2017.03, University of Granada, 18071 Granada, Spain
- Department of Statistics and Operations Research, University of Granada, 18071 Granada, Spain
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8
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Relationship between Lower Urinary Tract Symptoms and Prostatic Urethral Stiffness Using Strain Elastography: Initial Experiences. J Clin Med 2019; 8:jcm8111929. [PMID: 31717594 PMCID: PMC6912549 DOI: 10.3390/jcm8111929] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/01/2019] [Accepted: 11/07/2019] [Indexed: 12/29/2022] Open
Abstract
We attempted to visualize the periurethral stiffness of prostatic urethras using strain elastography in the midsagittal plane of transrectal ultrasonography (TRUS) and to evaluate periurethral stiffness patterns in relation to lower urinary tract symptoms (LUTS). A total of 250 men were enrolled. The stiffness patterns of the entire prostate and individual zones were evaluated using strain elastography during a TRUS examination. After excluding 69 men with inappropriate elastography images, subjects were divided according to periurethral stiffness into either group A (low periurethral stiffness, N = 80) or group B (high periurethral stiffness, N = 101). There were significant differences in patient age (p = 0.022), transitional zone volume (p = 0.001), transitional zone index (p = 0.33), total international prostate symptom score (IPSS) (p < 0.001), IPSS-voiding subscore (p < 0.001), IPSS-storage subscore (p < 0.001), and quality of life (QoL) score (p = 0.002) between groups A and B. After adjusting for relevant variables, significant differences in total IPSS, IPSS-voiding subscore, and QoL score were maintained. Men with high periurethral stiffness were associated with worse urinary symptoms than those with low periurethral stiffness, suggesting that periurethral stiffness might play an important role in the development of LUTS.
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de Assis AM, Moreira AM, Carnevale FC, Marcelino ASZ, de Oliveira Cerri LM, Antunes AA, Srougi M, Cerri GG. Effects of Prostatic Artery Embolization on the Dynamic Component of Benign Prostate Hyperplasia as Assessed by Ultrasound Elastography: A Pilot Series. Cardiovasc Intervent Radiol 2019; 42:1001-1007. [PMID: 30993369 DOI: 10.1007/s00270-019-02220-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/08/2019] [Indexed: 12/11/2022]
Abstract
PURPOSE To determine the effects of prostatic artery embolization (PAE) on prostatic elasticity as assessed by Ultrasound Elastography (US-E), as well as to describe the feasibility and role of US-E as a novel tool in both pre- and post-PAE evaluation. MATERIALS AND METHODS This is a prospective, single-center investigation that included eight patients undergoing PAE for treatment of lower urinary tract symptoms (LUTS) attributed to benign prostate hyperplasia (BPH). Baseline and 3-month follow-up evaluations were performed and included prostate-specific antigen (PSA), uroflowmetry, pelvic magnetic resonance imaging and clinical assessment using the International Prostate Symptom Score (IPSS) questionnaire and the IPSS-Quality of life (QoL) item. US-E with measurement of the prostatic Elastic Modulus (EM) was performed before PAE and at 1-month follow-up. RESULTS After PAE, US-E showed a significant reduction of prostatic EM as assessed in kPa (33.14 vs. 47.24, - 29.8%, p = 0.002) and in m/s (3.75 vs. 4.63, - 19.0%, p < 0.001). Also, the transitional/peripheral zone ratio was significantly reduced by 45.36% (0.53 vs. 0.97, p < 0.05). All eight patients presented with significant LUTS improvement after PAE (p < 0.05 for IPSS, QoL, prostate volume, peak urinary flow rate and PSA). CONCLUSIONS Findings described in this study suggest that PAE significantly reduces prostatic EM, leading to a positive effect on BPH dynamic component related to prostatic elasticity. Also, it features US-E as an additional tool for pre- and post-PAE evaluation, describing a novel indication for this technology.
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Affiliation(s)
- André Moreira de Assis
- Interventional Radiology Department, Radiology Institute, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil.
- Interventional Radiology Department, Sírio-Libanês Hospital, Adma Jafet Street, 115 Bela Vista, São Paulo, SP, 01308-050, Brazil.
| | - Airton Mota Moreira
- Interventional Radiology Department, Radiology Institute, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil
- Interventional Radiology Department, Sírio-Libanês Hospital, Adma Jafet Street, 115 Bela Vista, São Paulo, SP, 01308-050, Brazil
| | - Francisco Cesar Carnevale
- Interventional Radiology Department, Radiology Institute, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil
- Interventional Radiology Department, Sírio-Libanês Hospital, Adma Jafet Street, 115 Bela Vista, São Paulo, SP, 01308-050, Brazil
| | | | | | - Alberto Azoubel Antunes
- Urology Department, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil
| | - Miguel Srougi
- Urology Department, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil
| | - Giovanni Guido Cerri
- Radiology Department, Sírio-Libanês Hospital, Adma Jafet Street, 115, Bela Vista, São Paulo, SP, 01308-050, Brazil
- Radiology Institute, University of Sao Paulo Medical School, Dr. Enéas de Carvalho Aguiar Avenue, 255, Cerqueira César, São Paulo, SP, 05403-000, Brazil
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Accurate validation of ultrasound imaging of prostate cancer: a review of challenges in registration of imaging and histopathology. J Ultrasound 2018; 21:197-207. [PMID: 30062440 PMCID: PMC6113189 DOI: 10.1007/s40477-018-0311-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 07/11/2018] [Indexed: 01/20/2023] Open
Abstract
As the development of modalities for prostate cancer (PCa) imaging advances, the challenge of accurate registration between images and histopathologic ground truth becomes more pressing. Localization of PCa, rather than detection, requires a pixel-to-pixel validation of imaging based on histopathology after radical prostatectomy. Such a registration procedure is challenging for ultrasound modalities; not only the deformations of the prostate after resection have to be taken into account, but also the deformation due to the employed transrectal probe and the mismatch in orientation between imaging planes and pathology slices. In this work, we review the latest techniques to facilitate accurate validation of PCa localization in ultrasound imaging studies and extrapolate a general strategy for implementation of a registration procedure.
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11
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Bayat S, Azizi S, Daoud MI, Nir G, Imani F, Gerardo CD, Yan P, Tahmasebi A, Vignon F, Sojoudi S, Wilson S, Iczkowski KA, Lucia MS, Goldenberg L, Salcudean SE, Abolmaesumi P, Mousavi P. Investigation of Physical Phenomena Underlying Temporal-Enhanced Ultrasound as a New Diagnostic Imaging Technique: Theory and Simulations. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2018; 65:400-410. [PMID: 29505407 DOI: 10.1109/tuffc.2017.2785230] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Temporal-enhanced ultrasound (TeUS) is a novel noninvasive imaging paradigm that captures information from a temporal sequence of backscattered US radio frequency data obtained from a fixed tissue location. This technology has been shown to be effective for classification of various in vivo and ex vivo tissue types including prostate cancer from benign tissue. Our previous studies have indicated two primary phenomena that influence TeUS: 1) changes in tissue temperature due to acoustic absorption and 2) micro vibrations of tissue due to physiological vibration. In this paper, first, a theoretical formulation for TeUS is presented. Next, a series of simulations are carried out to investigate micro vibration as a source of tissue characterizing information in TeUS. The simulations include finite element modeling of micro vibration in synthetic phantoms, followed by US image generation during TeUS imaging. The simulations are performed on two media, a sparse array of scatterers and a medium with pathology mimicking scatterers that match nuclei distribution extracted from a prostate digital pathology data set. Statistical analysis of the simulated TeUS data shows its ability to accurately classify tissue types. Our experiments suggest that TeUS can capture the microstructural differences, including scatterer density, in tissues as they react to micro vibrations.
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12
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Alan B, Utangaç M, Göya C, Dağgülli M. Role of Acoustic Radiation Force Impulse (ARFI) Elastography in Determination of Severity of Benign Prostate Hyperplasia. Med Sci Monit 2016; 22:4523-4528. [PMID: 27876713 PMCID: PMC5132425 DOI: 10.12659/msm.898676] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Background The aim of this study was to investigate the potential contribution of acoustic radiation force impulse (ARFI) elastography to the determination of the severity of benign prostate hypertrophy (BPH) by performing shear wave velocity (SWV) measurements of the prostate using ARFI technology. Material/Methods Sixty BPH patients and 40 healthy volunteers were included in this study. SWV measurements of the prostate were performed by transabdominal ultrasonography (US), both in the BPH patients and control subjects. The BPH patients also underwent uroflowmetry measurements. Using the International Prostate Symptom Score (IPSS), the BPH patients were divided into two subgroups, a mild-to-moderate BPH group and a severe BPH group, to compare SWV values. Results The BPH patients had higher SWV values for the central area of the prostate compared to the control subjects (2.52±0.59 m/s and 1.47±0.42 m/s, p<0.01). The SWV values of the central area of prostate were higher in the severe BPH group compared to the mild-to-moderate BPH group (2.62±0.58 and 2.25±0.55, p=0.02). Conclusions Our ARFI elastography results indicated that the central prostate SWV values of BPH patients were significantly higher relative to those of a healthy control group. The central prostate SWV values increased in proportion to the increased severity of BPH. Measurement of SWV by ARFI technology constitutes a non-invasive alternative to other methods for the determination of BPH severity.
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Affiliation(s)
- Bircan Alan
- Department of Radiology, Dicle University, Medical Faculty, Diyarbakır, Turkey
| | - Mazhar Utangaç
- Department of Neurology, Dicle University, Medical Faculty, Diyarbakır, Turkey
| | - Cemil Göya
- Department of Neurology, Dicle University, Medical Faculty, Diyarbakır, Turkey
| | - Mansur Dağgülli
- Department of Neurology, Dicle University, Medical Faculty, Diyarbakır, Turkey
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13
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Palmeri ML, Glass TJ, Miller ZA, Rosenzweig SJ, Buck A, Polascik TJ, Gupta RT, Brown AF, Madden J, Nightingale KR. Identifying Clinically Significant Prostate Cancers using 3-D In Vivo Acoustic Radiation Force Impulse Imaging with Whole-Mount Histology Validation. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:1251-62. [PMID: 26947445 PMCID: PMC4860099 DOI: 10.1016/j.ultrasmedbio.2016.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 12/10/2015] [Accepted: 01/11/2016] [Indexed: 05/04/2023]
Abstract
Overly aggressive prostate cancer (PCa) treatment adversely affects patients and places an unnecessary burden on our health care system. The inability to identify and grade clinically significant PCa lesions is a factor contributing to excessively aggressive PCa treatment, such as radical prostatectomy, instead of more focal, prostate-sparing procedures such as cryotherapy and high-dose radiation therapy. We have performed 3-D in vivo B-mode and acoustic radiation force impulse (ARFI) imaging using a mechanically rotated, side-fire endorectal imaging array to identify regions suspicious for PCa in 29 patients being treated with radical prostatectomies for biopsy-confirmed PCa. Whole-mount histopathology analyses were performed to identify regions of clinically significant/insignificant PCa lesions, atrophy and benign prostatic hyperplasia. Regions of suspicion for PCa were reader-identified in ARFI images based on boundary delineation, contrast, texture and location. These regions of suspicion were compared with histopathology identified lesions using a nearest-neighbor regional localization approach. Of all clinically significant lesions identified on histopathology, 71.4% were also identified using ARFI imaging, including 79.3% of posterior and 33.3% of anterior lesions. Among the ARFI-identified lesions, 79.3% corresponded to clinically significant PCa lesions, with these lesions having higher indices of suspicion than clinically insignificant PCa. ARFI imaging had greater sensitivity for posterior versus anterior lesions because of greater displacement signal-to-noise ratio and finer spatial sampling. Atrophy and benign prostatic hyperplasia can cause appreciable prostate anatomy distortion and heterogeneity that confounds ARFI PCa lesion identification; however, in general, ARFI regions of suspicion did not coincide with these benign pathologies.
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Affiliation(s)
- Mark L Palmeri
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.
| | - Tyler J Glass
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Zachary A Miller
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Stephen J Rosenzweig
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA
| | - Andrew Buck
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Thomas J Polascik
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Rajan T Gupta
- Department of Radiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Alison F Brown
- School of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - John Madden
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
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14
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Liu J, Ji Y, Ai H, Ning B, Zhao J, Zhang Y, Dun G. Liver Shear-Wave Velocity and Serum Fibrosis Markers to Diagnose Hepatic Fibrosis in Patients with Chronic Viral Hepatitis B. Korean J Radiol 2016; 17:396-404. [PMID: 27134527 PMCID: PMC4842858 DOI: 10.3348/kjr.2016.17.3.396] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 01/28/2016] [Indexed: 12/18/2022] Open
Abstract
Objective To compare several noninvasive indices of fibrosis in chronic viral hepatitis B, including liver shear-wave velocity (SWV), hyaluronic acid (HA), collagen type IV (CIV), procollagen type III (PCIII), and laminin (LN). Materials and Methods Acoustic radiation force impulse (ARFI) was performed in 157 patients with chronic viral hepatitis B and in 30 healthy volunteers to measure hepatic SWV (m/s) in a prospective study. Serum markers were acquired on the morning of the same day of the ARFI evaluation. Receiver operating characteristic (ROC) analysis was performed to evaluate and compare the accuracies of SWV and serum markers using METAVIR scoring from liver biopsy as a reference standard. Results The most accurate test for diagnosing fibrosis F ≥ 1 was SWV with the area under the ROC curve (AUC) of 0.913, followed by LN (0.744), HA (0.701), CIV (0.690), and PCIII (0.524). The best test for diagnosing F ≥ 2 was SWV (AUC of 0.851), followed by CIV (0.671), HA (0.668), LN (0.562), and PCIII (0.550). The best test for diagnosing F ≥ 3 was SWV (0.854), followed by CIV (0.693), HA (0.675), PCIII (0.591), and LN (0.548). The best test for diagnosing F = 4 was SWV (0.965), followed by CIV (0.804), PCIII (0.752), HA (0.744), and LN (0.662). SWV combined with HA and CIV did not improve diagnostic accuracy (AUC = 0.931 for F ≥ 1, 0.863 for F ≥ 2, 0.855 for F ≥ 3, 0.960 for F = 4). Conclusion The performance of SWV in diagnosing liver fibrosis is superior to that of serum markers. However, the combination of SWV, HA, and CIV does not increase the accuracy of diagnosing liver fibrosis and cirrhosis.
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Affiliation(s)
- Jianxue Liu
- Department of Ultrasonography, Baoji Central Hospital, Baoji, Shaanxi 721008, China.; Department of Ultrasonography, The First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Yonghao Ji
- Department of Ultrasonography, Baoji Central Hospital, Baoji, Shaanxi 721008, China
| | - Hong Ai
- Department of Ultrasonography, The First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Bo Ning
- Department of Infectious Disease, Baoji Central Hospital, Baoji, Shaanxi 721008, China
| | - Junzhi Zhao
- Department of Ultrasonography, Baoji Central Hospital, Baoji, Shaanxi 721008, China
| | - Yaoren Zhang
- Department of Ultrasonography, Baoji Central Hospital, Baoji, Shaanxi 721008, China
| | - Guoliang Dun
- Department of Ultrasonography, Baoji Central Hospital, Baoji, Shaanxi 721008, China
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15
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Sarkar S, Das S. A Review of Imaging Methods for Prostate Cancer Detection. Biomed Eng Comput Biol 2016; 7:1-15. [PMID: 26966397 PMCID: PMC4777886 DOI: 10.4137/becb.s34255] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 01/07/2016] [Accepted: 01/11/2016] [Indexed: 12/21/2022] Open
Abstract
Imaging is playing an increasingly important role in the detection of prostate cancer (PCa). This review summarizes the key imaging modalities-multiparametric ultrasound (US), multiparametric magnetic resonance imaging (MRI), MRI-US fusion imaging, and positron emission tomography (PET) imaging-used in the diagnosis and localization of PCa. Emphasis is laid on the biological and functional characteristics of tumors that rationalize the use of a specific imaging technique. Changes to anatomical architecture of tissue can be detected by anatomical grayscale US and T2-weighted MRI. Tumors are known to progress through angiogenesis-a fact exploited by Doppler and contrast-enhanced US and dynamic contrast-enhanced MRI. The increased cellular density of tumors is targeted by elastography and diffusion-weighted MRI. PET imaging employs several different radionuclides to target the metabolic and cellular activities during tumor growth. Results from studies using these various imaging techniques are discussed and compared.
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Affiliation(s)
| | - Sudipta Das
- Department of Medicine, University of California, San Diego, CA, USA
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16
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Anvari A, Barr RG, Dhyani M, Samir AE. Clinical application of sonoelastography in thyroid, prostate, kidney, pancreas, and deep venous thrombosis. ACTA ACUST UNITED AC 2015; 40:709-22. [PMID: 25750099 DOI: 10.1007/s00261-015-0383-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This article reviews the clinical applications of current ultrasound elastography methods in non-hepatic conditions including thyroid nodules, prostate cancer, chronic kidney disease, solid renal lesions, pancreatic lesions, and deep vein thrombosis. Pathophysiology alters tissue mechanical properties via ultrastructural changes including fibrosis, increased cellularity, bleeding, and necrosis, creating a target biomarker, which can be imaged qualitatively or quantitatively with US elastography. US elastography methods can add information to conventional US methods and improve the diagnostic performance of conventional US in a range of disease processes.
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Affiliation(s)
- Arash Anvari
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA
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17
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Chun GC, Chiang HJ, Lin KH, Li CM, Chen PJ, Chen T. Ultrasound Elasticity Imaging System with Chirp-Coded Excitation for Assessing Biomechanical Properties of Elasticity Phantom. MATERIALS (BASEL, SWITZERLAND) 2015; 8:8392-8413. [PMID: 28793718 PMCID: PMC5458841 DOI: 10.3390/ma8125458] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/03/2015] [Accepted: 11/24/2015] [Indexed: 11/16/2022]
Abstract
The biomechanical properties of soft tissues vary with pathological phenomenon. Ultrasound elasticity imaging is a noninvasive method used to analyze the local biomechanical properties of soft tissues in clinical diagnosis. However, the echo signal-to-noise ratio (eSNR) is diminished because of the attenuation of ultrasonic energy by soft tissues. Therefore, to improve the quality of elastography, the eSNR and depth of ultrasound penetration must be increased using chirp-coded excitation. Moreover, the low axial resolution of ultrasound images generated by a chirp-coded pulse must be increased using an appropriate compression filter. The main aim of this study is to develop an ultrasound elasticity imaging system with chirp-coded excitation using a Tukey window for assessing the biomechanical properties of soft tissues. In this study, we propose an ultrasound elasticity imaging system equipped with a 7.5-MHz single-element transducer and polymethylpentene compression plate to measure strains in soft tissues. Soft tissue strains were analyzed using cross correlation (CC) and absolution difference (AD) algorithms. The optimal parameters of CC and AD algorithms used for the ultrasound elasticity imaging system with chirp-coded excitation were determined by measuring the elastographic signal-to-noise ratio (SNRe) of a homogeneous phantom. Moreover, chirp-coded excitation and short pulse excitation were used to measure the elasticity properties of the phantom. The elastographic qualities of the tissue-mimicking phantom were assessed in terms of Young's modulus and elastographic contrast-to-noise ratio (CNRe). The results show that the developed ultrasound elasticity imaging system with chirp-coded excitation modulated by a Tukey window can acquire accurate, high-quality elastography images.
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Affiliation(s)
- Guan-Chun Chun
- Department of Biomedical Engineering, National Cheng Kung University, Tainan City 70101, Taiwan.
| | - Hsing-Jung Chiang
- Department of Biomedical Engineering, National Cheng Kung University, Tainan City 70101, Taiwan.
| | - Kuan-Hung Lin
- Department of Biomedical Engineering, National Cheng Kung University, Tainan City 70101, Taiwan.
| | - Chien-Ming Li
- Division of Infectious Diseases, Department of Medicine of Chi Mei Medical Center, Tainan City 71004, Taiwan.
| | - Pei-Jarn Chen
- Department of Electrical Engineering, Southern Taiwan University of Science and Technology, Tainan City 71005, Taiwan.
| | - Tainsong Chen
- Department of Biomedical Engineering, National Cheng Kung University, Tainan City 70101, Taiwan.
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18
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Schalk SG, Postema A, Saidov TA, Demi L, Smeenge M, de la Rosette JJMCH, Wijkstra H, Mischi M. 3D surface-based registration of ultrasound and histology in prostate cancer imaging. Comput Med Imaging Graph 2015; 47:29-39. [PMID: 26647110 DOI: 10.1016/j.compmedimag.2015.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 07/13/2015] [Accepted: 11/03/2015] [Indexed: 11/20/2022]
Abstract
Several transrectal ultrasound (TRUS)-based techniques aiming at accurate localization of prostate cancer are emerging to improve diagnostics or to assist with focal therapy. However, precise validation prior to introduction into clinical practice is required. Histopathology after radical prostatectomy provides an excellent ground truth, but needs accurate registration with imaging. In this work, a 3D, surface-based, elastic registration method was developed to fuse TRUS images with histopathologic results. To maximize the applicability in clinical practice, no auxiliary sensors or dedicated hardware were used for the registration. The mean registration errors, measured in vitro and in vivo, were 1.5±0.2 and 2.1±0.5mm, respectively.
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Affiliation(s)
- Stefan G Schalk
- Department of Electrical Engineering, Eindhoven University of Technology, Postbus 513, 5600 MB Eindhoven, The Netherlands.
| | - Arnoud Postema
- Department of Urology, AMC University Hospital, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Tamerlan A Saidov
- Department of Electrical Engineering, Eindhoven University of Technology, Postbus 513, 5600 MB Eindhoven, The Netherlands
| | - Libertario Demi
- Department of Electrical Engineering, Eindhoven University of Technology, Postbus 513, 5600 MB Eindhoven, The Netherlands
| | - Martijn Smeenge
- Department of Urology, AMC University Hospital, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | | | - Hessel Wijkstra
- Department of Electrical Engineering, Eindhoven University of Technology, Postbus 513, 5600 MB Eindhoven, The Netherlands; Department of Urology, AMC University Hospital, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Massimo Mischi
- Department of Electrical Engineering, Eindhoven University of Technology, Postbus 513, 5600 MB Eindhoven, The Netherlands
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19
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Controlled Study of Traditional Ultrasound and Ultrasound Elastography on the Diagnosis of Breast Masses. Ultrasound Q 2015; 31:250-4. [DOI: 10.1097/ruq.0000000000000195] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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20
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Imani F, Abolmaesumi P, Gibson E, Khojaste A, Gaed M, Moussa M, Gomez JA, Romagnoli C, Leveridge M, Chang S, Siemens DR, Fenster A, Ward AD, Mousavi P. Computer-Aided Prostate Cancer Detection Using Ultrasound RF Time Series: In Vivo Feasibility Study. IEEE TRANSACTIONS ON MEDICAL IMAGING 2015; 34:2248-2257. [PMID: 25935029 DOI: 10.1109/tmi.2015.2427739] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
UNLABELLED This paper presents the results of a computer-aided intervention solution to demonstrate the application of RF time series for characterization of prostate cancer, in vivo. METHODS We pre-process RF time series features extracted from 14 patients using hierarchical clustering to remove possible outliers. Then, we demonstrate that the mean central frequency and wavelet features extracted from a group of patients can be used to build a nonlinear classifier which can be applied successfully to differentiate between cancerous and normal tissue regions of an unseen patient. RESULTS In a cross-validation strategy, we show an average area under receiver operating characteristic curve (AUC) of 0.93 and classification accuracy of 80%. To validate our results, we present a detailed ultrasound to histology registration framework. CONCLUSION Ultrasound RF time series results in differentiation of cancerous and normal tissue with high AUC.
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21
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El Fattah Hassan Gadalla AA, El Rahman SFA, Anis SE, El-Sayed khalil M. Value of ultrasound elastography versus transrectal prostatic biopsy in prostatic cancer detection. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2015. [DOI: 10.1016/j.ejrnm.2015.05.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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22
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Imani F, Ramezani M, Nouranian S, Gibson E, Khojaste A, Gaed M, Moussa M, Gomez JA, Romagnoli C, Leveridge M, Chang S, Fenster A, Siemens DR, Ward AD, Mousavi P, Abolmaesumi P. Ultrasound-Based Characterization of Prostate Cancer Using Joint Independent Component Analysis. IEEE Trans Biomed Eng 2015; 62:1796-1804. [PMID: 25720016 DOI: 10.1109/tbme.2015.2404300] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE This paper presents the results of a new approach for selection of RF time series features based on joint independent component analysis for in vivo characterization of prostate cancer. METHODS We project three sets of RF time series features extracted from the spectrum, fractal dimension, and the wavelet transform of the ultrasound RF data on a space spanned by five joint independent components. Then, we demonstrate that the obtained mixing coefficients from a group of patients can be used to train a classifier, which can be applied to characterize cancerous regions of a test patient. RESULTS In a leave-one-patient-out cross validation, an area under receiver operating characteristic curve of 0.93 and classification accuracy of 84% are achieved. CONCLUSION Ultrasound RF time series can be used to accurately characterize prostate cancer, in vivo without the need for exhaustive search in the feature space. SIGNIFICANCE We use joint independent component analysis for systematic fusion of multiple sets of RF time series features, within a machine learning framework, to characterize PCa in an in vivo study.
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Affiliation(s)
- Farhad Imani
- Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada
| | | | | | - Eli Gibson
- Robarts Research Institute, Western University
| | | | - Mena Gaed
- Robarts Research Institute, Western University
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23
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Palmeri ML, Miller ZA, Glass TJ, Garcia-Reyes K, Gupta RT, Rosenzweig SJ, Kauffman C, Polascik TJ, Buck A, Kulbacki E, Madden J, Lipman SL, Rouze NC, Nightingale KR. B-mode and acoustic radiation force impulse (ARFI) imaging of prostate zonal anatomy: comparison with 3T T2-weighted MR imaging. ULTRASONIC IMAGING 2015; 37:22-41. [PMID: 25060914 PMCID: PMC4423560 DOI: 10.1177/0161734614542177] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Prostate cancer (PCa) is the most common non-cutaneous malignancy among men in the United States and the second leading cause of cancer-related death. Multi-parametric magnetic resonance imaging (mpMRI) has gained recent popularity to characterize PCa. Acoustic Radiation Force Impulse (ARFI) imaging has the potential to aid PCa diagnosis and management by using tissue stiffness to evaluate prostate zonal anatomy and lesions. MR and B-mode/ARFI in vivo imaging datasets were compared with one another and with gross pathology measurements made immediately after radical prostatectomy. Images were manually segmented in 3D Slicer to delineate the central gland (CG) and prostate capsule, and 3D models were rendered to evaluate zonal anatomy dimensions and volumes. Both imaging modalities showed good correlation between estimated organ volume and gross pathologic weights. Ultrasound and MR total prostate volumes were well correlated (R(2) = 0.77), but B-mode images yielded prostate volumes that were larger (16.82% ± 22.45%) than MR images, due to overestimation of the lateral dimension (18.4% ± 13.9%), with less significant differences in the other dimensions (7.4% ± 17.6%, anterior-to-posterior, and -10.8% ± 13.9%, apex-to-base). ARFI and MR CG volumes were also well correlated (R(2) = 0.85). CG volume differences were attributed to ARFI underestimation of the apex-to-base axis (-28.8% ± 9.4%) and ARFI overestimation of the lateral dimension (21.5% ± 14.3%). B-mode/ARFI imaging yielded prostate volumes and dimensions that were well correlated with MR T2-weighted image (T2WI) estimates, with biases in the lateral dimension due to poor contrast caused by extraprostatic fat. B-mode combined with ARFI imaging is a promising low-cost, portable, real-time modality that can complement mpMRI for PCa diagnosis, treatment planning, and management.
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Affiliation(s)
- Mark L Palmeri
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Zachary A Miller
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Tyler J Glass
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | | | - Rajan T Gupta
- Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Stephen J Rosenzweig
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | | | - Thomas J Polascik
- Department of Surgery (Urology), Duke University Medical Center, Durham, NC, USA
| | - Andrew Buck
- Department of Pathology, Duke University Medical Center, Durham, NC, USA
| | - Evan Kulbacki
- Department of Pathology, Duke University Medical Center, Durham, NC, USA
| | - John Madden
- Department of Pathology, Duke University Medical Center, Durham, NC, USA
| | - Samantha L Lipman
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Ned C Rouze
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Kathryn R Nightingale
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
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24
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Detection and characterisation of biopsy tissue using quantitative optical coherence elastography (OCE) in men with suspected prostate cancer. Cancer Lett 2014; 357:121-128. [PMID: 25444932 DOI: 10.1016/j.canlet.2014.11.021] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/28/2014] [Accepted: 11/07/2014] [Indexed: 01/18/2023]
Abstract
We present first quantitative three-dimensional (3D) data sets recorded using optical coherence elastography (OCE) for the diagnosis and detection of prostate cancer (PCa). 120 transrectal ultrasound guided prostate biopsy specimens from 10 men suspected with prostate cancer were imaged using OCE. 3D quantitative mechanical assessment of biopsy specimens obtained in kilopascals (kPa) at an interval of 40 µm was compared with histopathology. Sensitivity, specificity, and positive and negative predictive values were calculated for OCE in comparison to histopathology. The results show OCE imaging could reliably differentiate between benign prostate tissue, acinar atypical hyperplasia, prostatic intraepithelial neoplasia and malignant PCa. The sensitivity and specificity of OCE for the detection of prostate cancer was 0.98 and 0.91 with AUC > 0.99. Quantitative 3D OCE based on the assessment of mechanical properties of tissues can reliably differentiate prostate tissue specimen in an ex-vivo setting. This is a promising imaging modality for characterising different grades of cancers.
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25
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Multi-parametric 3D quantitative ultrasound vibro-elastography imaging for detecting palpable prostate tumors. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2014. [PMID: 25333163 DOI: 10.1007/978-3-319-10404-1_70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
In this article, we describe a system for detecting dominant prostate tumors, based on a combination of features extracted from a novel multi-parametric quantitative ultrasound elastography technique. The performance of the system was validated on a data-set acquired from n = 10 patients undergoing radical prostatectomy. Multi-frequency steady-state mechanical excitations were applied to each patient's prostate through the perineum and prostate tissue displacements were captured by a transrectal ultrasound system. 3D volumetric data including absolute value of tissue elasticity, strain and frequency-response were computed for each patient. Based on the combination of all extracted features, a random forest classification algorithm was used to separate cancerous regions from normal tissue, and to compute a measure of cancer probability. Registered whole mount histopathology images of the excised prostate gland were used as a ground truth of cancer distribution for classifier training. An area under receiver operating characteristic curve of 0.82 +/- 0.01 was achieved in a leave-one-patient-out cross validation. Our results show the potential of multi-parametric quantitative elastography for prostate cancer detection for the first time in a clinical setting, and justify further studies to establish whether the approach can have clinical use.
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Li SM, Li GX, Fu DM, Wang Y, Dang LQ. Liver fibrosis evaluation by ARFI and APRI in chronic hepatitis C. World J Gastroenterol 2014; 20:9528-9533. [PMID: 25071348 PMCID: PMC4110585 DOI: 10.3748/wjg.v20.i28.9528] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 04/09/2014] [Accepted: 05/05/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the value of liver fibrosis assessment by acoustic radiation force impulse (ARFI) and the AST/PLT ratio index (APRI) in chronic hepatitis C patients.
METHODS: One hundred and twenty eight patients with chronic hepatitis C were examined using ARFI elastometry and APRI, calculated according to known formulae. The gold standard of liver biopsy was referred; ROC curve analysis was used to assess all ARFI and APRI values. The corresponding cut-off values, sensitivities, and specificities were calculated and compared. In addition, the correlation of liver fibrosis stages in chronic hepatitis C patients with ARFI measurements and APRI were also tested to evaluate significant data.
RESULTS: The values of ARFI in S1-S4 were 1.23 ± 0.34 m/s, 1.48 ± 0.43 m/s, 2.06 ± 0.45 m/s, and 2.30 ± 0.87 m/s. The values of APRI in S1-S4 were 0.31 ± 0.45 m/s, 0.28 ± 0.38 m/s, 0.58 ± 0.59 m/s and 0.65 ± 0.34 m/s. ARFI (r = 0.649, P < 0.05) showed a better correlation with liver fibrosis stages in chronic hepatitis C than APRI (r = 0.478, P < 0.05). The areas under the ROC curves for ARFI and APRI were 0.775 and 0.721 for stages ≥ S2, 0.901 and 0.787 for stages ≥ S3, and 0.792 and 0.780 for S = 4, respectively.
CONCLUSION: Both ARFI and APRI could evaluate liver fibrosis stages in chronic hepatitis C. ARFI is more accurate than the APRI index.
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27
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Zhu Y, Zhang X, Zheng Y, Chen X, Shen Y, Lin H, Guo Y, Wang T, Chen S. Quantitative analysis of liver fibrosis in rats with shearwave dispersion ultrasound vibrometry: comparison with dynamic mechanical analysis. Med Eng Phys 2014; 36:1401-7. [PMID: 24835187 DOI: 10.1016/j.medengphy.2014.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 04/02/2014] [Accepted: 04/04/2014] [Indexed: 12/19/2022]
Abstract
Ultrasonic elastography, a non-invasive technique for assessing the elasticity properties of tissues, has shown promising results for disease diagnosis. However, biological soft tissues are viscoelastic in nature. Shearwave dispersion ultrasound vibrometry (SDUV) can simultaneously measure the elasticity and viscosity of tissue using shear wave propagation speeds at different frequencies. In this paper, the viscoelasticity of rat livers was measured quantitatively by SDUV for normal (stage F0) and fibrotic livers (stage F2). Meanwhile, an independent validation study was presented in which SDUV results were compared with those derived from dynamic mechanical analysis (DMA), which is the only mechanical test that simultaneously assesses the viscoelastic properties of tissue. Shear wave speeds were measured at frequencies of 100, 200, 300 and 400 Hz with SDUV and the storage moduli and loss moduli were measured at the frequency range of 1-40 Hz with DMA. The Voigt viscoelastic model was used in the two methods. The mean elasticity and viscosity obtained by SDUV ranged from 0.84±0.13 kPa (F0) to 1.85±0.30 kPa (F2) and from 1.12±0.11 Pa s (F0) to 1.70±0.31 Pa s (F2), respectively. The mean elasticity and viscosity derived from DMA ranged from 0.62±0.09 kPa (F0) to 1.70±0.84 kPa (F2) and from 3.38±0.32 Pa s (F0) to 4.63±1.30 Pa s (F2), respectively. Both SDUV and DMA demonstrated that the elasticity of rat livers increased from stage F0 to F2, a finding which was consistent with previous literature. However, the elasticity measurements obtained by SDUV had smaller differences than those obtained by DMA, whereas the viscosities obtained by the two methods were obviously different. We suggest that the difference could be related to factors such as tissue microstructure, the frequency range, sample size and the rheological model employed. For future work we propose some improvements in the comparative tests between SDUV and DMA, such as enlarging the harmonic frequency range of the shear wave to highlight the role of viscosity, finding an appropriate rheological model to improve the accuracy of tissue viscoelasticity estimations.
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Affiliation(s)
- Ying Zhu
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Xinyu Zhang
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Yi Zheng
- Department of Electrical and Computer Engineering, St. Cloud State University, St. Cloud, MN 56301, USA
| | - Xin Chen
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Yuanyuan Shen
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Haoming Lin
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Yanrong Guo
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Tianfu Wang
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China
| | - Siping Chen
- National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen 518160, China.
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Cui G, Yang Z, Zhang W, Li B, Sun F, Xu C, Wang K. Evaluation of acoustic radiation force impulse imaging for the clinicopathological typing of renal fibrosis. Exp Ther Med 2013; 7:233-235. [PMID: 24348796 PMCID: PMC3860982 DOI: 10.3892/etm.2013.1377] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 10/21/2013] [Indexed: 01/22/2023] Open
Abstract
This study aimed to explore the assessment value of virtual touch quantization (VTQ) for the clinicopathological typing of renal fibrosis. The quantitative detection of 76 patients with nephropathy was performed using acoustic radiation force impulse imaging (ARFI). The extent of the renal fibrosis in each patient was confirmed using ultrasound-guided biopsy pathology. The VTQ values were compared with the degree of renal fibrosis in order to analyze the correlation between them. Patients were divided pathologically into four groups, as follows: non-fibrosis (n=14), mild fibrosis (n=40), moderate fibrosis (n=21) and severe fibrosis (n=1). Compared with the non-fibrosis group, the VTQ values of the mild and moderate fibrosis groups were significantly increased (P<0.01); however, there was no significant difference between the VTQ values of the mild and moderate fibrosis groups (P>0.05). According to the receiver operating characteristic (ROC) curve, a VTQ value of renal parenchyma of >1.67 m/sec was determined to be an indicator of renal fibrosis, with a sensitivity of 86.3% and a specificity of 83.3%. VTQ technology may be significant in the assessment of the extent of renal fibrosis.
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Affiliation(s)
- Guanghe Cui
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Zhi Yang
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Wenxiao Zhang
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Baowei Li
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Fang Sun
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Cui Xu
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
| | - Kun Wang
- Department of Ultrasonic Medicine, The Affiliated Hospital of Binzhou Medical College, Binzhou, Shandong 256603, P.R. China
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Palmeri ML, Feltovich H, Homyk AD, Carlson LC, Hall TJ. Evaluating the feasibility of acoustic radiation force impulse shear wave elasticity imaging of the uterine cervix with an intracavity array: a simulation study. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2013; 60:2053-64. [PMID: 24081254 PMCID: PMC4423534 DOI: 10.1109/tuffc.2013.2796] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The uterine cervix softens, shortens, and dilates throughout pregnancy in response to progressive disorganization of its layered collagen microstructure. This process is an essential part of normal pregnancy, but premature changes are associated with preterm birth. Clinically, there are no reliable noninvasive methods to objectively measure cervical softening or assess cervical microstructure. The goal of these preliminary studies was to evaluate the feasibility of using an intracavity ultrasound array to generate acoustic radiation force impulse (ARFI) excitations in the uterine cervix through simulation, and to optimize the acoustic radiation force (ARF) excitation for shear wave elasticity imaging (SWEI) of the tissue stiffness. The cervix is a unique soft tissue target for SWEI because it has significantly greater acoustic attenuation (α = 1.3 to 2.0 dB·cm(-1)·MHz(-)1) than other soft tissues, and the pathology being studied tends to lead to an increase in tissue compliance, with healthy cervix being relatively stiff compared with other soft tissues (E ≈ 25 kPa). Additionally, the cervix can only be accessed in vivo using a transvaginal or catheter-based array, which places additional constraints on the excitation focal characteristics that can be used during SWEI. Finite element method (FEM) models of SWEI show that larger-aperture, catheter-based arrays can utilize excitation frequencies up to 7 MHz to generate adequate focal gain up to focal depths 10 to 15 mm deep, with higher frequencies suffering from excessive amounts of near-field acoustic attenuation. Using full-aperture excitations can yield ~40% increases in ARFI-induced displacements, but also restricts the depth of field of the excitation to ~0.5 mm, compared with 2 to 6 mm, which limits the range that can be used for shear wave characterization of the tissue. The center-frequency content of the shear wave particle velocity profiles ranges from 1.5 to 2.5 kHz, depending on the focal configuration and the stiffness of the material being imaged. Overall, SWEI is possible using catheter-based imaging arrays to generate adequate displacements in cervical tissue for shear wave imaging, although specific considerations must be made when optimizing these arrays for this shear wave imaging application.
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Affiliation(s)
- Mark L. Palmeri
- Biomedical Engineering Department, Duke University, Durham, NC,
| | - Helen Feltovich
- Medical Physics Department, University of Wisconsin–Madison, Madison, WI
- Maternal Fetal Medicine Department, Intermountain Healthcare, Provo, UT
| | | | - Lindsey C. Carlson
- Medical Physics Department, University of Wisconsin–Madison, Madison, WI
| | - Timothy J. Hall
- Medical Physics Department, University of Wisconsin–Madison, Madison, WI
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Doherty JR, Trahey GE, Nightingale KR, Palmeri ML. Acoustic radiation force elasticity imaging in diagnostic ultrasound. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2013; 60:685-701. [PMID: 23549529 PMCID: PMC3679553 DOI: 10.1109/tuffc.2013.2617] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The development of ultrasound-based elasticity imaging methods has been the focus of intense research activity since the mid-1990s. In characterizing the mechanical properties of soft tissues, these techniques image an entirely new subset of tissue properties that cannot be derived with conventional ultrasound techniques. Clinically, tissue elasticity is known to be associated with pathological condition and with the ability to image these features in vivo; elasticity imaging methods may prove to be invaluable tools for the diagnosis and/or monitoring of disease. This review focuses on ultrasound-based elasticity imaging methods that generate an acoustic radiation force to induce tissue displacements. These methods can be performed noninvasively during routine exams to provide either qualitative or quantitative metrics of tissue elasticity. A brief overview of soft tissue mechanics relevant to elasticity imaging is provided, including a derivation of acoustic radiation force, and an overview of the various acoustic radiation force elasticity imaging methods.
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Affiliation(s)
- Joshua R Doherty
- Department of Biomedical Engineering, Duke University, Durham, NC, USA.
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Ultrasound-based characterization of prostate cancer: an in vivo clinical feasibility study. MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION : MICCAI ... INTERNATIONAL CONFERENCE ON MEDICAL IMAGE COMPUTING AND COMPUTER-ASSISTED INTERVENTION 2013; 16:279-86. [PMID: 24579151 DOI: 10.1007/978-3-642-40763-5_35] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
UNLABELLED This paper presents the results of an in vivo clinical study to accurately characterize prostate cancer using new features of ultrasound RF time series. METHODS The mean central frequency and wavelet features of ultrasound RF time series from seven patients are used along with an elaborate framework of ultrasound to histology registration to identify and verify cancer in prostate tissue regions as small as 1.7 mm x 1.7 mm. RESULTS In a leave-one-patient-out cross-validation strategy, an average classification accuracy of 76% and the area under ROC curve of 0.83 are achieved using two proposed RF time series features. The results statistically significantly outperform those achieved by previously reported features in the literature. The proposed features show the clinical relevance of RF time series for in vivo characterization of cancer.
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Dhanaliwala A.H, Hossack JA, Mauldin FW. Assessing and improving acoustic radiation force image quality using a 1.5-D transducer design. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2012; 59:1602-8. [PMID: 22828855 PMCID: PMC4047991 DOI: 10.1109/tuffc.2012.2360] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
A 1.5-D transducer array was proposed to improve acoustic radiation force impulse (ARFI) imaging signal-to-noise ratio (SNRARFI) and image contrast relative to a conventional 1-D array. To predict performance gains from the proposed 1.5-D transducer array, an analytical model for SNRARFI upper bound was derived. The analytical model and 1.5-D ARFI array were validated using a finite element modelbased numerical simulation framework. The analytical model demonstrated good agreement with numerical results (correlation coefficient = 0.995), and simulated lesion images yielded a significant (2.92 dB; p < 0.001) improvement in contrast-tonoise ratio when rendered using the 1.5-D ARFI array.
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Hsu SJ, Byram BC, Bouchard RR, Dumont DM, Wolf PD, Trahey GE. Acoustic radiation force impulse imaging of mechanical stiffness propagation in myocardial tissue. ULTRASONIC IMAGING 2012; 34:142-58. [PMID: 22972912 PMCID: PMC3500656 DOI: 10.1177/0161734612456580] [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] [Indexed: 05/04/2023]
Abstract
Acoustic radiation force impulse (ARFI) imaging has been shown to be capable of imaging local myocardial stiffness changes throughout the cardiac cycle. Expanding on these results, the authors present experiments using cardiac ARFI imaging to visualize and quantify the propagation of mechanical stiffness during ventricular systole. In vivo ARFI images of the left ventricular free wall of two exposed canine hearts were acquired. Images were formed while the heart was externally paced by one of two electrodes positioned on the epicardial surface and either side of the imaging plane. Two-line M-mode ARFI images were acquired at a sampling frequency of 120 Hz while the heart was paced from an external stimulating electrode. Two-dimensional ARFI images were also acquired, and an average propagation velocity across the lateral field of view was calculated. Directions and speeds of myocardial stiffness propagation were measured and compared with the propagations derived from the local electrocardiogram (ECG), strain, and tissue velocity measurements estimated during systole. In all ARFI images, the direction of myocardial stiffness propagation was seen to be away from the stimulating electrode and occurred with similar velocity magnitudes in either direction. When compared with the local epicardial ECG, the mechanical stiffness waves were observed to travel in the same direction as the propagating electrical wave and with similar propagation velocities. In a comparison between ARFI, strain, and tissue velocity imaging, the three methods also yielded similar propagation velocities.
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34
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Balleyguier C, Canale S, Ben Hassen W, Vielh P, Bayou EH, Mathieu MC, Uzan C, Bourgier C, Dromain C. Breast elasticity: principles, technique, results: an update and overview of commercially available software. Eur J Radiol 2012; 82:427-34. [PMID: 22445593 DOI: 10.1016/j.ejrad.2012.03.001] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Breast ultrasound elasticity evaluation has become a routine tool in addition to diagnostic ultrasound during the last five years. Two elasticity evaluation modes are currently available: free-hand elastography and shear-wave elastography (SWE). Most of the commercially available elastography scanners have specific procedures which must be understood by the users. Free-hand elastography usually displays qualitative imaging such as an elastogram, but most of the companies now use it to quantify the relative stiffness between a lesion and the surrounding breast tissue. SWE is a new mode theoretically independent of the sonographer which displays more quantitative information, and can be useful for characterizing breast lesions. Recent studies on elastography suggest that elasticity imaging can increase B-mode accuracy and specificity in differentiating benign and malignant breast lesions. This functional imaging mode could help reduce the number of biopsies performed for benign breast lesions. This review gives a detailed description of the main commercially available systems and the results of current applications in the evaluation of breast elasticity.
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Affiliation(s)
- C Balleyguier
- Radiology Department, Institut Gustave Roussy, Villejuif, France.
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35
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Abern MR, Tsivian M, Polascik TJ. Focal Therapy of Prostate Cancer: Evidence-based Analysis for Modern Selection Criteria. Curr Urol Rep 2012; 13:160-9. [DOI: 10.1007/s11934-012-0241-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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36
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Zhang Y, Tang J, Li YM, Fei X, He EH, Li QY, Shi HY. The contribution of strain patterns in characterization of prostate peripheral zone lesions at transrectal ultrasonography. Acta Radiol 2012; 53:119-26. [PMID: 22139716 DOI: 10.1258/ar.2011.110504] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Elasticity is an important characteristic of tissue. During an elastography examination, various strain images of lesions are observed, and a suitable classification of strain patterns (SP) may provide vital diagnostic information about lesions. Numerous studies have shown that ultrasound elastography can improve the detection of prostate cancer, but the diagnostic value of SP classification has not yet been fully evaluated. PURPOSE To investigate the contribution of SP on the characterization of prostate peripheral zone lesions by transrectal real-time tissue elastography (TRTE) in combination with conventional transrectal ultrasonography (TRUS). MATERIAL AND METHODS One hundred and seventy-one patients with suspected prostate cancer underwent TRUS and TRTE examinations. The SPs of the suspicious lesions were classified into five scores by TRTE according to the degree and distribution of strain. All findings were confirmed by transrectal systematic 12-core biopsies and targeted biopsies for suspicious areas detecting by TRUS and/or TRTE. RESULTS One hundred and forty-eight of 171 patients had high-quality TRTE imaging and were included into the study. When a cut-off point of SP score III was used, the area under the receiver-operating characteristic curve (AUC) was, respectively, 0.75 (95% CI: 0.67-0.83), 0.85 (95% CI: 0.78-0.91) and 0.84 (95% CI: 0.77-0.91) for the diagnosis of prostate cancer by TRUS, TRTE and TRTE + TRUS. A linear tendency of SP and Gleason scores was observed in scores III-V. The detection rate of prostate cancer using TRTE-targeted biopsy (75.8%) was significantly higher than that of systematic 12-core biopsy plus TRUS-targeted biopsy (14.5%) (P = 0.00). CONCLUSION This study suggests the significant contribution of SP on characterization of prostate peripheral zone lesions and the improvement of TRTE-targeted biopsy on detection of prostate cancer.
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Affiliation(s)
| | | | | | | | | | | | - Huai-yin Shi
- Department of Pathology, Chinese People's Liberation Army General Hospital, Beijing, China
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37
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Zhai L, Polascik TJ, Foo WC, Rosenzweig S, Palmeri ML, Madden J, Nightingale KR. Acoustic radiation force impulse imaging of human prostates: initial in vivo demonstration. ULTRASOUND IN MEDICINE & BIOLOGY 2012; 38:50-61. [PMID: 22104533 PMCID: PMC3403291 DOI: 10.1016/j.ultrasmedbio.2011.10.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 08/31/2011] [Accepted: 10/07/2011] [Indexed: 05/04/2023]
Abstract
Reliably detecting prostate cancer (PCa) has been a challenge for current imaging modalities. Acoustic radiation force impulse (ARFI) imaging is an elasticity imaging method that uses remotely generated, focused acoustic beams to probe tissue stiffness. A previous study on excised human prostates demonstrated ARFI images portray various prostatic structures and has the potential to guide prostate needle biopsy with improved sampling accuracy. The goal of this study is to demonstrate the feasibility of ARFI imaging to portray internal structures and PCa in the human prostate in vivo. Custom ARFI imaging sequences were designed and implemented using a modified Siemens Antares™ scanner with a three-dimensional (3-D) wobbler, end-firing, trans-cavity transducer, EV9F4. Nineteen patients were consented and imaged immediately preceding surgical prostatectomy. Pathologies and anatomic structures were identified in histologic slides by a pathologist blinded to ARFI data and were then registered with structures found in ARFI images. The results demonstrated that when PCa is visible, it generally appears as bilaterally asymmetric stiff structures; benign prostatic hyperplasia (BPH) appears heterogeneous with a nodular texture; the verumontanum and ejaculatory ducts appears softer compared with surrounding tissue, which form a unique 'V' shape; and the boundary of the transitional zone (TZ) forms a stiff rim separating the TZ from the peripheral zone (PZ). These characteristic appearances of prostatic structures are consistent with those found in our previous study of prostate ARFI imaging on excised human prostates. Compared with the matched B-mode images, ARFI images, in general, portray prostate structures with higher contrast. With the end-firing transducer used for this study, ARFI depth penetration was limited to 22 mm. Image contrast and resolution were decreased as compared with the previous ex vivo study due to the small transducer aperture. Even with these limitations, this study suggests ARFI imaging holds promise for guidance of targeted prostate needle biopsy and focal therapy, as well as aiding assessment of changes during watchful waiting/active surveillance.
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Affiliation(s)
- Liang Zhai
- Department of Biomedical Engineering, Duke University, Durham, NC 27708-0281, USA.
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38
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Biomechanical Modeling of the Prostate for Procedure Guidance and Simulation. STUDIES IN MECHANOBIOLOGY, TISSUE ENGINEERING AND BIOMATERIALS 2012. [DOI: 10.1007/8415_2012_121] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Wells PNT, Liang HD. Medical ultrasound: imaging of soft tissue strain and elasticity. J R Soc Interface 2011; 8:1521-49. [PMID: 21680780 PMCID: PMC3177611 DOI: 10.1098/rsif.2011.0054] [Citation(s) in RCA: 305] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Accepted: 05/23/2011] [Indexed: 02/06/2023] Open
Abstract
After X-radiography, ultrasound is now the most common of all the medical imaging technologies. For millennia, manual palpation has been used to assist in diagnosis, but it is subjective and restricted to larger and more superficial structures. Following an introduction to the subject of elasticity, the elasticity of biological soft tissues is discussed and published data are presented. The basic physical principles of pulse-echo and Doppler ultrasonic techniques are explained. The history of ultrasonic imaging of soft tissue strain and elasticity is summarized, together with a brief critique of previously published reviews. The relevant techniques-low-frequency vibration, step, freehand and physiological displacement, and radiation force (displacement, impulse, shear wave and acoustic emission)-are described. Tissue-mimicking materials are indispensible for the assessment of these techniques and their characteristics are reported. Emerging clinical applications in breast disease, cardiology, dermatology, gastroenterology, gynaecology, minimally invasive surgery, musculoskeletal studies, radiotherapy, tissue engineering, urology and vascular disease are critically discussed. It is concluded that ultrasonic imaging of soft tissue strain and elasticity is now sufficiently well developed to have clinical utility. The potential for further research is examined and it is anticipated that the technology will become a powerful mainstream investigative tool.
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Affiliation(s)
- Peter N T Wells
- School of Engineering, Cardiff University, Queen's Buildings, The Parade, Cardiff CF24 3AA, UK.
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40
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Sarvazyan A, Hall TJ, Urban MW, Fatemi M, Aglyamov SR, Garra BS. AN OVERVIEW OF ELASTOGRAPHY - AN EMERGING BRANCH OF MEDICAL IMAGING. Curr Med Imaging 2011; 7:255-282. [PMID: 22308105 PMCID: PMC3269947 DOI: 10.2174/157340511798038684] [Citation(s) in RCA: 255] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
From times immemorial manual palpation served as a source of information on the state of soft tissues and allowed detection of various diseases accompanied by changes in tissue elasticity. During the last two decades, the ancient art of palpation gained new life due to numerous emerging elasticity imaging (EI) methods. Areas of applications of EI in medical diagnostics and treatment monitoring are steadily expanding. Elasticity imaging methods are emerging as commercial applications, a true testament to the progress and importance of the field.In this paper we present a brief history and theoretical basis of EI, describe various techniques of EI and, analyze their advantages and limitations, and overview main clinical applications. We present a classification of elasticity measurement and imaging techniques based on the methods used for generating a stress in the tissue (external mechanical force, internal ultrasound radiation force, or an internal endogenous force), and measurement of the tissue response. The measurement method can be performed using differing physical principles including magnetic resonance imaging (MRI), ultrasound imaging, X-ray imaging, optical and acoustic signals.Until recently, EI was largely a research method used by a few select institutions having the special equipment needed to perform the studies. Since 2005 however, increasing numbers of mainstream manufacturers have added EI to their ultrasound systems so that today the majority of manufacturers offer some sort of Elastography or tissue stiffness imaging on their clinical systems. Now it is safe to say that some sort of elasticity imaging may be performed on virtually all types of focal and diffuse disease. Most of the new applications are still in the early stages of research, but a few are becoming common applications in clinical practice.
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41
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Palmeri ML, Nightingale KR. Acoustic radiation force-based elasticity imaging methods. Interface Focus 2011; 1:553-64. [PMID: 22419986 PMCID: PMC3262278 DOI: 10.1098/rsfs.2011.0023] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Accepted: 05/18/2011] [Indexed: 12/14/2022] Open
Abstract
Conventional diagnostic ultrasound images portray differences in the acoustic properties of soft tissues, whereas ultrasound-based elasticity images portray differences in the elastic properties of soft tissues (i.e. stiffness, viscosity). The benefit of elasticity imaging lies in the fact that many soft tissues can share similar ultrasonic echogenicities, but may have different mechanical properties that can be used to clearly visualize normal anatomy and delineate pathological lesions. Acoustic radiation force-based elasticity imaging methods use acoustic radiation force to transiently deform soft tissues, and the dynamic displacement response of those tissues is measured ultrasonically and is used to estimate the tissue's mechanical properties. Both qualitative images and quantitative elasticity metrics can be reconstructed from these measured data, providing complimentary information to both diagnose and longitudinally monitor disease progression. Recently, acoustic radiation force-based elasticity imaging techniques have moved from the laboratory to the clinical setting, where clinicians are beginning to characterize tissue stiffness as a diagnostic metric, and commercial implementations of radiation force-based ultrasonic elasticity imaging are beginning to appear on the commercial market. This article provides an overview of acoustic radiation force-based elasticity imaging, including a review of the relevant soft tissue material properties, a review of radiation force-based methods that have been proposed for elasticity imaging, and a discussion of current research and commercial realizations of radiation force based-elasticity imaging technologies.
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Affiliation(s)
- Mark L. Palmeri
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
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42
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Palmeri ML, Nightingale KR. What challenges must be overcome before ultrasound elasticity imaging is ready for the clinic? IMAGING IN MEDICINE 2011; 3:433-444. [PMID: 22171226 PMCID: PMC3235674 DOI: 10.2217/iim.11.41] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ultrasound elasticity imaging has been a research interest for the past 20 years with the goal of generating novel images of soft tissues based on their material properties (i.e., stiffness and viscosity). The motivation for such an imaging modality lies in the fact that many soft tissues can share similar ultrasonic echogenicities, but may have very different mechanical properties that can be used to clearly visualize normal anatomy and delineate diseased tissues and masses. Recently, elasticity imaging techniques have moved from the laboratory to the clinical setting, where clinicians are beginning to characterize tissue stiffness as a diagnostic metric and commercial implementations of ultrasonic elasticity imaging are beginning to appear on the market. This article provides a foundation for elasticity imaging, an overview of current research and commercial realizations of elasticity imaging technology and a perspective on the current successes, limitations and potential for improvement of these imaging technologies.
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Affiliation(s)
- Mark L Palmeri
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
- Department of Anesthesiology, Duke University, Durham, NC 27708, USA
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Curiel L, Hynynen K. Localized harmonic motion imaging for focused ultrasound surgery targeting. ULTRASOUND IN MEDICINE & BIOLOGY 2011; 37:1230-9. [PMID: 21683514 PMCID: PMC3130203 DOI: 10.1016/j.ultrasmedbio.2011.05.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 03/31/2011] [Accepted: 05/10/2011] [Indexed: 05/12/2023]
Abstract
Recently, an in vivo real-time ultrasound-based monitoring technique that uses localized harmonic motion (LHM) to detect changes in tissues during focused ultrasound surgery (FUS) has been proposed to control the exposure. This technique can potentially be used as well for targeting imaging. In the present study, we evaluated the potential of using LHM to detect changes in stiffness and the feasibility of using it for imaging purposes in phantoms and in vivo tumor detection. A single-element FUS transducer (80 mm focal length, 100 mm diameter, 1.485 MHz) was used for inducing a localized harmonic motion and a separate ultrasound diagnostic transducer excited by a pulser/receiver (5 kHz PRF, 5 MHz) was used to track motion. The motion was estimated using cross-correlation techniques on the acquired radio-frequency (RF) signal. Silicon phantom studies were performed to determine the size of inclusion that was possible to detect using this technique. Inclusions were discerned from the surroundings as a reduction on LHM amplitude and it was possible to depict inclusions as small as 4 mm. The amplitude of the induced LHM was always lower at the inclusions compared with the one obtained at the surroundings. Ten New Zealand rabbits had VX2 tumors implanted on their thighs and LHM was induced and measured at the tumor region. Tumors (as small as 10 mm in length and 4 mm in width) were discerned from the surroundings as a reduction on LHM amplitude.
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Affiliation(s)
- Laura Curiel
- Thunder Bay Regional Research Institute and Electrical Engineering, Lakehead University, Thunder Bay, Ontario, Canada.
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Parker KJ, Doyley MM, Rubens DJ. Imaging the elastic properties of tissue: the 20 year perspective. Phys Med Biol 2010; 56:R1-R29. [PMID: 21119234 DOI: 10.1088/0031-9155/56/1/r01] [Citation(s) in RCA: 257] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
After 20 years of innovation in techniques that specifically image the biomechanical properties of tissue, the evolution of elastographic imaging can be viewed from its infancy, through a proliferation of approaches to the problem to incorporation on research and then clinical imaging platforms. Ultimately this activity has culminated in clinical trials and improved care for patients. This remarkable progression represents a leading example of translational research that begins with fundamentals of science and engineering and progresses to needed improvements in diagnostic and monitoring capabilities applied to major categories of disease, surgery and interventional procedures. This review summarizes the fundamental principles, the timeline of developments in major categories of elastographic imaging, and concludes with recent results from clinical trials and forward-looking issues.
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Affiliation(s)
- K J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Hopeman Engineering Building, Box 270126, Rochester, NY 14627, USA.
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Goertz RS, Amann K, Heide R, Bernatik T, Neurath MF, Strobel D. An abdominal and thyroid status with Acoustic Radiation Force Impulse Elastometry--a feasibility study: Acoustic Radiation Force Impulse Elastometry of human organs. Eur J Radiol 2010; 80:e226-30. [PMID: 20971591 DOI: 10.1016/j.ejrad.2010.09.025] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 09/23/2010] [Indexed: 12/19/2022]
Abstract
PURPOSE Acoustic Radiation Force Impulse (ARFI) is a new method for the quantification of tissue elasticity. To date, ARFI technology has not been applied systematically to establish an abdominal and thyroid status. The aim of this prospective feasibility study was to evaluate ARFI elastometry performed on various healthy abdominal organs and the thyroid gland. MATERIAL AND METHODS 94 patients (43 females, 51 males) with a mean age of 54 years and 20 healthy controls were enrolled in the study. A routine ultrasound examination of the abdomen was scheduled in 72, and of the thyroid in 25. ARFI elastometry was performed in liver, spleen, pancreas, prostate, kidneys and thyroid gland with the ultrasound system Acuson S2000. ARFI values are proportional to tissue elasticity. Patients with ultrasonic or anamnestic evidence of diseased organs were excluded from the analysis. ARFI measurements were compared with the aid of the t-test and correlated using Spearman's correlation coefficient. RESULTS ARFI elastometry proved feasible and the measurements obtained in the various organs differed significantly. Among healthy organs the spleen showed the highest mean ARFI velocities, followed by the kidney, thyroid, pancreas and the prostate. The lowest ARFI values were regularly found in healthy liver. Measurements in the kidneys and the spleen showed high standard deviation. CONCLUSIONS ARFI elastometry may describe parenchymal stiffness of various abdominal organs and the thyroid gland. Further investigations are needed to compare these baseline findings in healthy organs with those of various tumours or diseases affecting the individual organs.
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Affiliation(s)
- R S Goertz
- Department of Internal Medicine 1, University of Erlangen, Ulmenweg 18, 91054 Erlangen, Germany.
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Zhai L, Madden J, Foo WC, Mouraviev V, Polascik TJ, Palmeri ML, Nightingale KR. Characterizing stiffness of human prostates using acoustic radiation force. ULTRASONIC IMAGING 2010; 32:201-13. [PMID: 21213566 PMCID: PMC3413332 DOI: 10.1177/016173461003200401] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Acoustic Radiation Force Impulse (ARFI) imaging has been previously reported to portray normal anatomic structures and pathologies in ex vivo human prostates with good contrast and resolution. These findings were based on comparison with histological slides and McNeal's zonal anatomy. In ARFI images, the central zone (CZ) appears darker (smaller displacement) than other anatomic zones and prostate cancer (PCa) is darker than normal tissue in the peripheral zone (PZ). Since displacement amplitudes in ARFI images are determined by both the underlying tissue stiffness and the amplitude of acoustic radiation force that varies with acoustic attenuation, one question that arises is how the relative displacements in prostate ARFI images are related to the underlying prostatic tissue stiffness. In linear, isotropic elastic materials and in tissues that are relatively uniform in acoustic attenuation (e.g., liver), relative displacement in ARFI images has been shown to be correlated with underlying tissue stiffness. However, the prostate is known to be heterogeneous. Variations in acoustic attenuation of prostatic structures could confound the interpretation of ARFI images due to the associated variations in the applied acoustic radiation force. Therefore, in this study, co-registered three-dimensional (3D) ARFI datasets and quantitative shear wave elasticity imaging (SWEI) datasets were acquired in freshly-excised human prostates to investigate the relationship between displacement amplitudes in ARFI prostate images and the matched reconstructed shear moduli. The lateral time-to-peak (LTTP) algorithm was applied to the SWEI data to compute the shear-wave speed and reconstruct the shear moduli. Five types of prostatic tissue (PZ, CZ, transition zone (TZ) and benign prostatic hyperplasia (BPH), PCa and atrophy) were identified, whose shear moduli were quantified to be 4.1 +/- 0.8 kPa, 9.9 +/- 0.9 kPa, 4.8 +/- 0.6 kPa, 10.0 +/- 1.0 kPa and 8.0 kPa, respectively. Linear regression was performed to compare ARFI displacement amplitudes and the inverse of the corresponding reconstructed shear moduli at multiple depths. The results indicate an inverse relation between ARFI displacement amplitude and reconstructed shear modulus at all depths. These findings support the conclusion that ARFI prostate images portray underlying tissue stiffness variations.
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Affiliation(s)
- Liang Zhai
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
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