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Yang Y, Shahryari M, Meyer T, Marticorena Garcia SR, Görner S, Salimi Majd M, Guo J, Braun J, Sack I, Tzschätzsch H. Explorative study using ultrasound time-harmonic elastography for stiffness-based quantification of skeletal muscle function. Z Med Phys 2024:S0939-3889(24)00027-8. [PMID: 38508947 DOI: 10.1016/j.zemedi.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 03/22/2024]
Abstract
Time-harmonic elastography (THE) is an emerging ultrasound imaging technique that allows full-field mapping of the stiffness of deep biological tissues. THE's unique ability to rapidly capture stiffness in multiple tissues has never been applied for imaging skeletal muscle. Therefore, we addressed the lack of data on temporal changes in skeletal muscle stiffness while simultaneously covering stiffness of different muscles. Acquiring repeated THE scans every five seconds we quantified shear-wave speed (SWS) as a marker of stiffness of the long head (LHB) and short head (SHB) of biceps brachii and of the brachialis muscle (B) in ten healthy volunteers. SWS was continuously acquired during a 3-min isometric preloading phase, a 3-min loading phase with different weights (4, 8, and 12 kg), and a 9-min postloading phase. In addition, we analyzed temporal SWS standard deviation (SD) as a marker of muscle contraction regulation. Our results (median [min, max]) showed both SWS at preloading (LHB: 1.04 [0.94, 1.12] m/s, SHB: 0.86 [0.78, 0.94] m/s, B: 0.96 [0.87, 1.09] m/s, p < 0.001) and the increase in SWS with loading weight to be muscle-specific (LHB: 0.010 [0.002, 0.019] m/s/kg, SHB: 0.022 [0.017, 0.042] m/s/kg, B: 0.039 [0.019, 0.062] m/s/kg, p < 0.001). Additionally, SWS during loading increased continuously over time by 0.022 [0.004, 0.051] m/s/min (p < 0.01). Using an exponential decay model, we found an average relaxation time of 27 seconds during postloading. Analogously, SWS SD at preloading was also muscle-specific (LHB: 0.018 [0.011, 0.029] m/s, SHB: 0.021 [0.015, 0.027] m/s, B: 0.024 [0.018, 0.037] m/s, p < 0.05) and increased by 0.005 [0.003, 0.008] m/s/kg (p < 0.01) with loading. SWS SD did not change over loading time and decreased immediately in the postloading phase. Taken together, THE of skeletal muscle is a promising imaging technique for in vivo quantification of stiffness and stiffness changes in multiple muscle groups within seconds. Both the magnitude of stiffness changes and their temporal variation during isometric exercise may reflect the functional status of skeletal muscle and provide additional information to the morphological measures obtained by conventional imaging modalities.
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Affiliation(s)
- Yang Yang
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Mehrgan Shahryari
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Tom Meyer
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Stephan Rodrigo Marticorena Garcia
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Steffen Görner
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Mahsa Salimi Majd
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jing Guo
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jürgen Braun
- Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Heiko Tzschätzsch
- Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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Wang Y, Tian XF, Cheng J, Xu XL, Cao JY, Dong Y, Dietrich CF. Normal value of virtual touch imaging quantification elastography in measurements of pancreas. Clin Hemorheol Microcirc 2024:CH232092. [PMID: 38393894 DOI: 10.3233/ch-232092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
OBJECTIVE To evaluate pancreatic tissue stiffness and provide a normal reference shear wave velocity (SWV) value of pancreas from healthy adults by Virtual Touch Imaging Quantification (VTIQ) measurements. METHODS Healthy adult volunteers without known history of hepatobiliary or pancreatic diseases were included. VTIQ elastography (Siemens ACUSON Sequoia, 5C-1 transducer) was used. SWV values were measured at the cephalic, corpus and tail of pancreas and replicated different operators' obtained data. Subgroups were classified according to the volunteers' gender, age, body mass index (BMI), depth of measurements and the echogenicity of the pancreas. RESULTS From February 2023 to July 2023, 33 healthy adult volunteers were included. The success rate of VTIQ measurements in cephalic, corpus and tail regions was 90.90 % (30/33), 96.97 % (32/33) and 90.90 % (30/33) respectively. The color elastograms of healthy adult pancreas showed uniform blue or simultaneously blue and green. The average SWV values were 0.97±0.26 m/s for cephalic, 0.91±0.24 m/s for corpus and 0.97±0.25 m/s for pancreatic tail respectively (P = 0.198). The mean SWV values of pancreas did not show significant difference with age, gender or depth (P > 0.05). BMI was an influence factor in the measurements of SWV values of cephalic and tail of pancreas (P < 0.05). Pancreas with hyperechoic parenchyma showed higher mean SWV values (P < 0.05). The intra-observer (ICC = 0.938 [95% CI: 0.869-0.971]) and the inter-observer (ICC = 0.887 [95% CI: 0.760-0.947]) agreements of VTIQ measurements were excellent. CONCLUSIONS The mean SWV value of the pancreas in healthy adults was 0.96±0.20 m/s (range: 0.52-1.74 m/s). VTIQ technique can be used in pancreatic stiffness measurements with good reliability.
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Affiliation(s)
- Ying Wang
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiao-Fan Tian
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Juan Cheng
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xin-Liang Xu
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jia-Ying Cao
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yi Dong
- Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Christoph F Dietrich
- Department Allgemeine Innere Medizin, Kliniken Hirslanden Beau Site, Salem und Permanence, Bern, Switzerland
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Aleef TA, Lobo J, Baghani A, Mohammed S, Eskandari H, Moradi H, Rohling R, Goldenberg SL, Morris WJ, Mahdavi SS, Salcudean SE. Multi-Frequency 3D Shear Wave Absolute Vibro-Elastography (S-WAVE) System for the Prostate. IEEE TRANSACTIONS ON MEDICAL IMAGING 2023; 42:3436-3450. [PMID: 37342953 DOI: 10.1109/tmi.2023.3288468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/23/2023]
Abstract
This article describes a novel system for quantitative and volumetric measurement of tissue elasticity in the prostate using simultaneous multi-frequency tissue excitation. Elasticity is computed by using a local frequency estimator to measure the three-dimensional local wavelengths of steady-state shear waves within the prostate gland. The shear wave is created using a mechanical voice coil shaker which transmits simultaneous multi-frequency vibrations transperineally. Radio frequency data is streamed directly from a BK Medical 8848 transrectal ultrasound transducer to an external computer where tissue displacement due to the excitation is measured using a speckle tracking algorithm. Bandpass sampling is used that eliminates the need for an ultra-fast frame rate to track the tissue motion and allows for accurate reconstruction at a sampling frequency that is below the Nyquist rate. A roll motor with computer control is used to rotate the transducer and obtain 3D data. Two commercially available phantoms were used to validate both the accuracy of the elasticity measurements as well as the functional feasibility of using the system for in vivo prostate imaging. The phantom measurements were compared with 3D Magnetic Resonance Elastography (MRE), where a high correlation of 96% was achieved. In addition, the system has been used in two separate clinical studies as a method for cancer identification. Qualitative and quantitative results of 11 patients from these clinical studies are presented here. Furthermore, an AUC of 0.87±0.12 was achieved for malignant vs. benign classification using a binary support vector machine classifier trained with data from the latest clinical study with leave one patient out cross-validation.
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Aleef TA, Zeng Q, Moradi H, Mohammed S, Curran T, Honarvar M, Rohling R, Mahdavi SS, Salcudean SE. 3-D Transducer Mounted Shear Wave Absolute Vibro-Elastography: Proof of Concept. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:1026-1038. [PMID: 37027576 DOI: 10.1109/tuffc.2023.3249795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Quantitative tissue stiffness characterization using ultrasound (US) has been shown to improve prostate cancer (PCa) detection in multiple studies. Shear wave absolute vibro-elastography (SWAVE) allows quantitative and volumetric assessment of tissue stiffness using external multifrequency excitation. This article presents a proof of concept of a first-of-a-kind 3-D hand-operated endorectal SWAVE system designed to be used during systematic prostate biopsy. The system is developed with a clinical US machine, requiring only an external exciter that can be mounted directly to the transducer. Subsector acquisition of radio frequency (RF) data allows imaging of shear waves with a high effective frame rate (up to 250 Hz). The system was characterized using eight different quality assurance phantoms. Due to the invasive nature of prostate imaging, at this early stage of development, validation of in vivo human tissue was instead carried out by intercostally scanning the livers of n = 7 healthy volunteers. The results are compared with 3-D magnetic resonance elastography (MRE) and an existing 3-D SWAVE system with a matrix array transducer (M-SWAVE). High correlations were found with MRE (99% in phantoms, 94% in liver data) and with M-SWAVE (99% in phantoms, 98% in liver data).
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Civale J, Parasaram V, Bamber JC, Harris EJ. High frequency ultrasound vibrational shear wave elastography for preclinical research. Phys Med Biol 2022; 67:245005. [PMID: 36410042 PMCID: PMC9728510 DOI: 10.1088/1361-6560/aca4b8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 11/21/2022] [Indexed: 11/22/2022]
Abstract
Preclinical evaluation of novel therapies using models of cancer is an important tool in cancer research, where imaging can provide non-invasive tools to characterise the internal structure and function of tumours. The short propagation paths when imaging tumours and organs in small animals allow the use of high frequencies for both ultrasound and shear waves, providing the opportunity for high-resolution shear wave elastography and hence its use for studying the heterogeneity of tissue elasticity, where heterogeneity may be a predictor of tissue response. Here we demonstrate vibrational shear wave elastography (VSWE) using a mechanical actuator to produce high frequency (up to 1000 Hz) shear waves in preclinical tumours, an alternative to the majority of preclinical ultrasound SWE studies where an acoustic radiation force impulse is required to create a relatively low-frequency broad-band shear-wave pulse. We implement VSWE with a high frequency (17.8 MHz) probe running a focused line-by-line ultrasound imaging sequence which as expected was found to offer improved detection of 1000 Hz shear waves over an ultrafast planar wave imaging sequence in a homogenous tissue-mimicking phantom. We test the VSWE in anex vivotumour xenograft, demonstrating the ability to detect shear waves up to 10 mm from the contactor position at 1000 Hz. By reducing the kernel size used for shear wave speed estimation to 1 mm we are able to produce shear wave speed images with spatial resolution of this order. Finally, we present VSWE data from xenograft tumoursin vivo, demonstrating the feasibility of the technique in mice under isoflurane sedation. Mean shear wave speeds in the tumours are in good agreements with those reported by previous authors. Characterising the frequency dependence of shear wave speed demonstrates the potential to quantify the viscoelastic properties of tumoursin vivo.
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Affiliation(s)
- J Civale
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, Sutton, United Kingdom
| | - V Parasaram
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, Sutton, United Kingdom
| | - JC Bamber
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, Sutton, United Kingdom
| | - EJ Harris
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, Sutton, United Kingdom
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Clevert DA, Jung EM, Weber MA, Lerchbaumer MH, Willinek W, Fischer T. Concepts in the Establishment of Interdisciplinary Ultrasound Centers: The Role of Radiology. ROFO-FORTSCHR RONTG 2022; 194:1322-1332. [PMID: 35850139 DOI: 10.1055/a-1853-7443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Ultrasound (US) is widely used as a fast and cost-efficient first-choice imaging technique without relevant side effects for a variety of diagnostic tasks. Due to technical advances, more complex and sophisticated methods such as color-coded duplex ultrasound, image fusion, contrast-enhanced ultrasound (CEUS), and ultrasound-guided interventions have become increasingly important in diagnostic algorithms. METHOD This study presents an overview of all aspects regarding the establishing of an interdisciplinary US center based on five representative examples in Germany. These aspects include topics of ultrasound education, research, economics, and administration. RESULTS The goal of an interdisciplinary US center is to bundle the use of equipment, staff, rooms, and infrastructure resources (optimization of equipment availability and use of new techniques) to expand the range of examinations, to promote resident training, and to boost continuing medical education of residents. This should result in better patient care and has additionally improved patient care while considering the added value for the participating institutions involved. Interdisciplinary US centers allow a reduction of the number of US devices needed in a hospital and more efficient use of available equipment through bedside time optimization by central organization within interdisciplinary management. The focused application of special US techniques such as CEUS or image fusion for complex, difficult interventions as well as the training and education of younger colleagues in using these techniques is centrally organized by experts and can be improved through the multidisciplinary experience available. CONCLUSION Organizational structures, sharing of materials, and standardization of diagnostic reports facilitate and accelerate cooperation with the referring specialty. KEY POINTS · Interdisciplinary US centers foster clinical collaboration, research, and jointly organized, standardized training.. · Economic aspects include optimization of available equipment, use of the latest US techniques, and centralization of organizational structures.. · Common terminology and standardized reporting increase the satisfaction of referring doctors. CITATION FORMAT · Clevert DA, Jung EM, Weber M et al. Concepts in the Establishment of Interdisciplinary Ultrasound Centers: The Role of Radiology. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1853-7443.
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Affiliation(s)
- Dirk Andre Clevert
- Institut für Klinische Radiologie, Campus Grosshadern, Klinikum der Universität München Großhadern, München, Germany
| | - Ernst Michael Jung
- Institut für Röntgendiagnostik, Universitätsklinikum Regensburg, Germany
| | - Marc-André Weber
- Universitätsmedizin Rostock, Diagnostische und Interventionelle Radiologie, Rostock, Germany
| | - Markus Herbert Lerchbaumer
- Department of Radiology, ChariteCentrum 6 Diagnostische und interventionelle Radiologie und Nuklearmedizin, Berlin, Germany
| | - Winfried Willinek
- 3. Center for Radiology, Neuroradiology, Sonography and Nuclear Medicine, Krankenhaus der Barmherzigen Brueder, Trier, Germany.,Radiology, University of Bonn, Germany
| | - Thomas Fischer
- Department of Radiology, ChariteCentrum 6 Diagnostische und interventionelle Radiologie und Nuklearmedizin, Berlin, Germany
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Poul SS, Ormachea J, Ge GR, Parker KJ. Comprehensive experimental assessments of rheological models' performance in elastography of soft tissues. Acta Biomater 2022; 146:259-273. [PMID: 35525481 DOI: 10.1016/j.actbio.2022.04.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 02/08/2023]
Abstract
Elastography researchers have utilized several rheological models to characterize soft tissue viscoelasticity over the past thirty years. Due to the frequency-dependent behavior of viscoelastic parameters as well as the different techniques and frequencies employed in various studies of soft tissues, rheological models have value in standardizing disparate techniques via explicit mathematical representations. However, the important question remains: which of the several available models should be considered for widespread adoption within a theoretical framework? We address this by evaluating the performance of three well established rheological models to characterize ex vivo bovine liver tissues: the Kelvin-Voigt (KV) model as a 2-parameter model, and the standard linear solid (SLS) and Kelvin-Voigt fractional derivative (KVFD) models as 3-parameter models. The assessments were based on the analysis of time domain behavior (using stress relaxation tests) and frequency domain behavior (by measuring shear wave speed (SWS) dispersion). SWS was measured over a wide range of frequency from 1 Hz to 1 kHz using three different tests: (i) harmonic shear tests using a rheometer, (ii) reverberant shear wave (RSW) ultrasound elastography scans, and (iii) RSW optical coherence elastography scans, with each test targeting a distinct frequency range. Our results demonstrated that the KVFD model produces the only mutually consistent rendering of time and frequency domain data for liver. Furthermore, it reduces to a 2-parameter model for liver (correspondingly to a 2-parameter "spring-pot" or power-law model for SWS dispersion) and provides the most accurate predictions of the material viscoelastic behavior in time (>98% accuracy) and frequency (>96% accuracy) domains. STATEMENT OF SIGNIFICANCE: Rheological models are applied in quantifying tissues viscoelastic properties. This study is unique in presenting comprehensive assessments of rheological models.
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Schulz M, Wilde ACB, Demir M, Müller T, Tacke F, Wree A. Shear wave elastography and shear wave dispersion imaging in primary biliary cholangitis-a pilot study. Quant Imaging Med Surg 2022; 12:1235-1242. [PMID: 35111619 DOI: 10.21037/qims-21-657] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/09/2021] [Indexed: 12/20/2022]
Abstract
Background Primary biliary cholangitis (PBC) is a chronic liver disease that can lead to liver fibrosis and cirrhosis. Two-dimensional shear wave elastography (2D-SWE) is a modern technique for fibrosis assessment. However, data regarding its performance in PBC is sparse. We aimed to characterize severity of liver disease in PBC patients using non-invasive 2D-SWE and the new methods of attenuation imaging (ATI) and shear wave dispersion imaging (SWD). Methods Twenty two PBC patients were examined with 2D-SWE, SWD and ATI, alongside established non-invasive fibrosis and steatosis assessment methods as well as liver function tests. Results Median 2D-SWE values were 1.48 m/s (range, 1.14-2.13 m/s) and 6.7 kPa (range, 3.8-14.7 kPa), respectively. Median SWD, ATI, transient elastography (TE) and controlled attenuation parameter (CAP) values were 13.9 m/s/kHz (range, 11.6-21 m/s/kHz), 0.57 dB/cm/MHz (range, 0.5-0.68 dB/cm/MHz), 7 kPa (range, 3.7-14.6 kPa), and 208 dB/m (range, 107-276 dB/m), respectively. 2D-SWE displayed a significant correlation with spleen length, platelet count, non-invasive fibrosis scores (FIB-4, APRI) and with TE. SWD correlated with alkaline phosphatase (ALP) levels, which is a prognostic marker in PBC. Conclusions Our findings add further evidence that 2D-SWE is a reliable method for fibrosis assessment in PBC. Even though the cohort size was small, the correlation of SWD with the prognostic marker ALP suggests a potentially valuable role of this new non-invasive method in evaluating liver disease activity in PBC.
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Affiliation(s)
- Marten Schulz
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
| | - Anne-Christin B Wilde
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
| | - Münevver Demir
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
| | - Tobias Müller
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
| | - Frank Tacke
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
| | - Alexander Wree
- Department of Hepatology and Gastroenterology, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum (CVK) and Campus Charité Mitte (CCM), Berlin, Germany
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Lim WTH, Ooi EH, Foo JJ, Ng KH, Wong JHD, Leong SS. Shear Wave Elastography: A Review on the Confounding Factors and Their Potential Mitigation in Detecting Chronic Kidney Disease. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:2033-2047. [PMID: 33958257 DOI: 10.1016/j.ultrasmedbio.2021.03.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 06/12/2023]
Abstract
Early detection of chronic kidney disease is important to prevent progression of irreversible kidney damage, reducing the need for renal transplantation. Shear wave elastography is ideal as a quantitative imaging modality to detect chronic kidney disease because of its non-invasive nature, low cost and portability, making it highly accessible. However, the complexity of the kidney architecture and its tissue properties give rise to various confounding factors that affect the reliability of shear wave elastography in detecting chronic kidney disease, thus limiting its application to clinical trials. The objective of this review is to highlight the confounding factors presented by the complex properties of the kidney, in addition to outlining potential mitigation strategies, along with the prospect of increasing the versatility and reliability of shear wave elastography in detecting chronic kidney disease.
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Affiliation(s)
- William T H Lim
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Malaysia
| | - Ean H Ooi
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Malaysia; Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Malaysia.
| | - Ji J Foo
- School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, Malaysia
| | - Kwan H Ng
- Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia; University of Malaya Research Imaging Centre, University of Malaya, Kuala Lumpur, Malaysia
| | - Jeannie H D Wong
- Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia; University of Malaya Research Imaging Centre, University of Malaya, Kuala Lumpur, Malaysia
| | - Sook S Leong
- Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia; Department of Biomedical Imaging, University of Malaya Medical Centre, Kuala Lumpur, Malaysia
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Ormachea J, Parker KJ. Comprehensive Viscoelastic Characterization of Tissues and the Inter-relationship of Shear Wave (Group and Phase) Velocity, Attenuation and Dispersion. ULTRASOUND IN MEDICINE & BIOLOGY 2020; 46:3448-3459. [PMID: 32988669 DOI: 10.1016/j.ultrasmedbio.2020.08.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/21/2020] [Accepted: 08/22/2020] [Indexed: 06/11/2023]
Abstract
We report shear wave phase and group velocity, dispersion and attenuation in oil-in-gelatin viscoelastic phantoms and in vivo liver data. Moreover, we measured the power law coefficient from each dispersion curve and used it, together with the shear wave velocity, to calculate an approximate value for attenuation that agrees with independent attenuation measurements. Results in phantoms exhibit good agreement for all parameters with respect to independent mechanical measurements. For in vivo data, the livers of 20 patients were scanned. Results were compared with pathology scores obtained from liver biopsies. Across these cases, increases in shear wave dispersion and attenuation were related to increased steatosis score. It was found that shear wave dispersion and attenuation are experimentally linked, consistent with simple predictions based on the rheology of tissues, and can be used individually or jointly to assess tissue viscosity. Thus, this study indicates the possible utility of using shear wave dispersion and attenuation to non-invasively and quantitatively assess steatosis.
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Affiliation(s)
- Juvenal Ormachea
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
| | - Kevin J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA
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Moga TV, Sporea I, Lupușoru R, Popescu A, Popa A, Bota S, Șirli R, Danilă M, Schlesinger A, Tzschätzsch H. Performance of a Noninvasive Time-Harmonic Elastography Technique for Liver Fibrosis Evaluation Using Vibration Controlled Transient Elastography as Reference Method. Diagnostics (Basel) 2020; 10:diagnostics10090653. [PMID: 32878078 PMCID: PMC7554698 DOI: 10.3390/diagnostics10090653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 12/15/2022] Open
Abstract
AIM This study aimed to evaluate the diagnosis performance of time-harmonic elastography (THE) technique in real life in assessing liver fibrosis, considering vibration-controlled transient elastography (VCTE) as a reference method. MATERIAL AND METHOD We prospectively evaluated outpatients from the gastroenterology department. Liver stiffness (LS) was measured by the THE system by dedicated operators, and by VCTE by experienced operators. The diagnostic accuracy of THE in staging liver fibrosis was assessed. We also performed an intra- and interobserver reproducibility sub-analysis on a sub-group of 27 subjects, where liver stiffness measurements (LSM) were performed by a novice, an elastography expert, and an ultrasound expert. RESULTS Of the 165 patients, using VCTE cut-off values, 49.6% were F0-F1, 15.7% were F2, 6.6% were F3, and 28.1% were F4. A direct, significant and strong correlation (r = 0.82) was observed between LSM assessed by VCTE and THE, p < 0.0001. The cut-off for ruling out liver cirrhosis (LC) by THE on our study group was <1.61 m/s (7.77 kPa)-AUROC = 0.90 [95% CI (0.82-0.93)], Se = 90.7%, Sp = 66.6%, PPV = 55.7%, NPV = 93.9%. The cut-off for ruling in LC by THE was >1.83 m/s (10 kPa)-AUROC = 0.90 [95% CI (0.82-0.93)], p < 0.0001, Se = 65.1%, Sp = 96.7%, PPV = 90.3%, NPV = 85.7%. The overall agreement between examiners was excellent: 0.94 (95% CI: 0.89-0.97); still, the ICCs were higher for the more experienced elastography examiner: 0.92 (95% CI: 0.82-0.96) vs. 0.94 (95% CI: 0.87-0.97) vs. 0.97 (95% CI: 0.95-0.99). CONCLUSIONS THE is a feasible and reproducible elastography technique that can accurately rule in and rule out advanced liver disease.
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Affiliation(s)
- Tudor Voicu Moga
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
| | - Ioan Sporea
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
| | - Raluca Lupușoru
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
- Department of Functional Science, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania
| | - Alina Popescu
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
- Correspondence: ; Tel.: +40-746-778-526
| | - Alexandru Popa
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
| | - Simona Bota
- Department of Internal Medicine and Gastroenterology, Hepatology, Endocrinology, Rheumatology and Nephrology and Emergency Medicine, Klinikum Klagenfurt am Wörthersee, 9020 Klagenfurt, Austria;
| | - Roxana Șirli
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
| | - Mirela Danilă
- Department of Gastroenterology and Hepatology, University of Medicine and Pharmacy “Victor Babeș”, 300041 Timișoara, Romania; (T.V.M.); (I.S.); (R.L.); (A.P.); (R.Ș.); (M.D.)
| | - Anton Schlesinger
- GAMPT mbH and Institute of Medical Informatics, 06217 Merseburg, Germany;
| | - Heiko Tzschätzsch
- Department of Radiology, Charité–Universitätsmedizin, 10115 Berlin, Germany;
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Heucke N, Wuensch T, Mohr J, Kaffarnik M, Arsenic R, Sinn B, Müller T, Pratschke J, Stockmann M, Sack I, Tzschätzsch H. Non-invasive structure-function assessment of the liver by 2D time-harmonic elastography and the dynamic Liver MAximum capacity (LiMAx) test. J Gastroenterol Hepatol 2019; 34:1611-1619. [PMID: 30756433 DOI: 10.1111/jgh.14629] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/23/2019] [Accepted: 02/10/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIM Accurate assessment of structural and functional characteristics of the liver could improve the diagnosis and the clinical management of patients with chronic liver diseases. However, the structure-function relationship in the progression of chronic liver disease remains elusive. The aim of this study is the combined measurement of liver function by the 13 C-methacetin Liver MAximum capacity (LiMAx) test and tissue-structure related stiffness by 2D time-harmonic elastography for the assessment of liver disease progression. METHODS LiMAx test and time-harmonic elastography were applied, and the serological scores fibrosis 4 index and aspartate aminotransferase to platelet ratio index were calculated in patients with chronic liver diseases (n = 75) and healthy control subjects (n = 22). In 47 patients who underwent surgery, fibrosis was graded by histological examination of the resected liver tissue. RESULTS LiMAx values correlated negatively with liver stiffness (r = -0.747), aminotransferase to platelet ratio index (r = -0.604), and fibrosis 4 (r = -0.573). Median (interquartile range) LiMAx values decreased with fibrosis progression from 395 μg/kg/h (371-460 μg/kg/h) in participants with no fibrosis to 173 μg/kg/h (126-309 μg/kg/h) in patients with severe fibrosis. Median liver stiffness increased progressively with the stage of fibrosis from no fibrosis (1.56 m/s [1.52-1.63 m/s]) to moderate fibrosis (1.60 m/s [1.54-1.67 m/s]) to severe fibrosis (1.85 m/s [1.76-1.92 m/s]). CONCLUSION Our findings show that structural changes in the liver due to progressing liver diseases and reflected by increased tissue stiffness correlate with a functional decline of the organ as reflected by a decreased metabolic capacity of the liver.
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Affiliation(s)
- Niklas Heucke
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tilo Wuensch
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Julia Mohr
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Magnus Kaffarnik
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ruza Arsenic
- Department of Pathology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Bruno Sinn
- Department of Pathology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tobias Müller
- Department of Gastroenterology and Hepatology, Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Johann Pratschke
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Martin Stockmann
- Department of Surgery, Campus Charité Mitte and Campus Virchow Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Heiko Tzschätzsch
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Ormachea J, Parker KJ, Barr RG. An initial study of complete 2D shear wave dispersion images using a reverberant shear wave field. ACTA ACUST UNITED AC 2019; 64:145009. [DOI: 10.1088/1361-6560/ab2778] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Otesteanu CF, Sanabria SJ, Goksel O. Robust Reconstruction of Elasticity Using Ultrasound Imaging and Multi-Frequency Excitations. IEEE TRANSACTIONS ON MEDICAL IMAGING 2018; 37:2502-2513. [PMID: 29994521 DOI: 10.1109/tmi.2018.2837390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biomedical parameters of tissue can be important indicators for clinical diagnosis. One such parameter that reflects tissue stiffness is elasticity, the imaging of which is called elastography. In this paper, we use displacements from harmonic excitations to solve the inverse problem of elasticity based on a finite-element method (FEM) formulation. This leads to iterative solution of nonlinear and nonconvex problems. In this paper, we show the importance and selection of viable initializations in numerical simulation studies and propose techniques for the fusion of multiple initializations for ideal reconstructions of unknown tissue as well as combining information from excitations at multiple frequencies. Results show that our method leads up to 76% decrease in root-mean-squared error (RMSE) and 9.9 dB increase in contrast-to-noise ratio (CNR) in simulations with noise, when compared to conventional iterative FEM without multiple initializations and frequencies. As the wave patterns in individually selected frequencies may introduce artifacts, a joint inverse-problem solution of multi-frequency excitations is introduced as a robust solution, where CNR improvements of up to 11.9 dB are observed. We also present the methods on a tissue-mimicking gelatin phantom study using mechanical excitation and ultrafast plane-wave ultrasound imaging, where the RMSE was improved by up to 51%. An experiment of ablation via heating an ex-vivo bovine liver shows that reconstruction artifacts are reduced with our proposed method.
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Simultaneous magnetic resonance and optical elastography acquisitions: Comparison of displacement images and shear modulus estimations using a single vibration source. J Mech Behav Biomed Mater 2018; 84:135-144. [DOI: 10.1016/j.jmbbm.2018.05.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/05/2018] [Accepted: 05/07/2018] [Indexed: 01/22/2023]
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Hudert CA, Tzschätzsch H, Guo J, Rudolph B, Bläker H, Loddenkemper C, Luck W, Müller HP, Baumgart DC, Hamm B, Braun J, Holzhütter HG, Wiegand S, Sack I. US Time-Harmonic Elastography: Detection of Liver Fibrosis in Adolescents with Extreme Obesity with Nonalcoholic Fatty Liver Disease. Radiology 2018; 288:99-106. [DOI: 10.1148/radiol.2018172928] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Christian A. Hudert
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Heiko Tzschätzsch
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jing Guo
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Birgit Rudolph
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Hendrik Bläker
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Christoph Loddenkemper
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Werner Luck
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Hans-Peter Müller
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Daniel C. Baumgart
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Bernd Hamm
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jürgen Braun
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Hermann-Georg Holzhütter
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Susanna Wiegand
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Ingolf Sack
- From the Center for Chronically Sick Children (C.A.H., S.W.), Departments of Radiology (H.T., J.G., B.H., I.S.), Pathology (B.R., H.B., C.L.), Pediatric Gastroenterology (W.L.), and Gastroenterology and Hepatology (H.P.M., D.C.B.), and the Institutes for Medical Informatics (J.B.) and Biochemistry (H.G.H.), Charité–Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
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Ormachea J, Castaneda B, Parker KJ. Shear Wave Speed Estimation Using Reverberant Shear Wave Fields: Implementation and Feasibility Studies. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:963-977. [PMID: 29477745 DOI: 10.1016/j.ultrasmedbio.2018.01.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 01/09/2018] [Accepted: 01/12/2018] [Indexed: 06/08/2023]
Abstract
Elastography is a modality that estimates tissue stiffness and, thus, provides useful information for clinical diagnosis. Attention has focused on the measurement of shear wave propagation; however, many methods assume shear wave propagation is unidirectional and aligned with the lateral imaging direction. Any deviations from the assumed propagation result in biased estimates of shear wave speed. To address these challenges, directional filters have been applied to isolate shear waves with different propagation directions. Recently, a new method was proposed for tissue stiffness estimation involving creation of a reverberant shear wave field propagating in all directions within the medium. These reverberant conditions lead to simple solutions, facile implementation and rapid viscoelasticity estimation of local tissue. In this work, this new approach based on reverberant shear waves was evaluated and compared with another well-known elastography technique using two calibrated elastic and viscoelastic phantoms. Additionally, the clinical feasibility of this technique was analyzed by assessing shear wave speed in human liver and breast tissues, in vivo. The results indicate that it is possible to estimate the viscoelastic properties in each scanned medium. Moreover, a better approach to estimation of shear wave speed was obtained when only the phase information was taken from the reverberant waves, which is equivalent to setting all magnitudes within the bandpass equal to unity: an idealization of a perfectly isotropic reverberant shear wave field.
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Affiliation(s)
- Juvenal Ormachea
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA.
| | - Benjamin Castaneda
- Laboratorio de Imagenes Medicas, Pontificia Universidad Catolica del Peru, Lima, Peru
| | - Kevin J Parker
- Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York, USA
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Berzigotti A, Ferraioli G, Bota S, Gilja OH, Dietrich CF. Novel ultrasound-based methods to assess liver disease: The game has just begun. Dig Liver Dis 2018; 50:107-112. [PMID: 29258813 DOI: 10.1016/j.dld.2017.11.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 11/08/2017] [Accepted: 11/27/2017] [Indexed: 12/11/2022]
Abstract
In the last 10 years the availability of ultrasound elastography allowed to diagnose and stage liver fibrosis in a non-invasive way and changed the clinical practice of hepatology. Newer ultrasound-based techniques to evaluate properties of the liver tissue other than fibrosis are emerging and will lead to a more complete characterization of the full spectrum of diffuse and focal liver disease. Since these methods are currently undergoing validation and go beyond elastography for liver tissue evaluation, they were not included in the recent guidelines regarding elastography issued by the European Federation of Societies in Ultrasound in Medicine and Biology. In this review paper, we outline the major advances in the field of ultrasound for liver applications, with special emphasis on techniques that could soon be part of the future armamentarium of ultrasound specialists devoted to the assessment of liver disease. Specifically, we discuss current and future ultrasound assessment of steatosis, spleen stiffness for portal hypertension, and elastography for the evaluation of focal liver lesions; we also provide a short glimpse into the next generation of ultrasound diagnostic methods.
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Affiliation(s)
- Annalisa Berzigotti
- Hepatology, University Clinic for Visceral Surgery and Medicine, Inselspital, University of Bern, Berne, Switzerland.
| | - Giovanna Ferraioli
- Clinical Sciences and Infectious Diseases Department, Fondazione IRCCS Policlinico San Matteo, University of Pavia, Pavia, Italy.
| | - Simona Bota
- Department of Gastroenterology, Hepatology, Nephrology and Endocrinology, Klinikum Klagenfurt, Klagenfurt am Wörthersee, Austria.
| | - Odd Helge Gilja
- National Centre for Ultrasound in Gastroenterology, Haukeland University Hospital, Bergen and Department of Clinical Medicine, University of Bergen, Norway.
| | - Christoph F Dietrich
- Department of Internal Medicine 2, Caritas Krankenhaus, Bad Mergentheim, Germany.
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Chapman T, Dubinsky T, Barr RG. Ultrasound Elastography of the Liver: What the Clinician Needs to Know. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2017; 36:1293-1304. [PMID: 28258611 DOI: 10.7863/ultra.16.08001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Todd Chapman
- University of Washington Medical Center, Seattle, Washington, USA
| | | | - Richard G Barr
- Northeast Ohio Medical University, Rootstown, Ohio, USA
- Radiology Consultants, Youngstown, Ohio, USA
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Ipek-Ugay S, Tzschätzsch H, Braun J, Fischer T, Sack I. Physiologic Reduction of Hepatic Venous Blood Flow by the Valsalva Maneuver Decreases Liver Stiffness. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2017; 36:1305-1311. [PMID: 28319252 DOI: 10.7863/ultra.16.07046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/09/2016] [Indexed: 06/06/2023]
Abstract
OBJECTIVES Liver stiffness increases after intake of food or water, suggesting that hepatic venous blood flow affects the results of elastographic measurements. This study investigated the correlation between in vivo liver stiffness and hepatic blood flow using the Valsalva maneuver for reducing intrahepatic venous blood flow. METHODS Intrahepatic changes in venous blood flow were assessed by sonography based on the pulsed wave Doppler velocity, vessel diameter assessment, and blood flow volume measurements in the portal vein and right hepatic vein. Time-harmonic elastography at 7 harmonic driving frequencies (30-60 Hz) was used to measure liver stiffness in the right liver lobe of 15 healthy volunteers. RESULTS The right hepatic vein diameter, flow volume, and peak pulsed wave velocity decreased during the Valsalva maneuver from mean ± SD values of 8.64 ± 1.85 to 6.55 ± 1.84 mm (P = .002), 0.53 ± 0.23 to 0.37 ± 0.26 L/min (P = .037), and 22.14 ± 4.87 to 17.38 ± 5.41 cm/s (P = .01), respectively. This maneuver decreased liver stiffness in all volunteers by a mean of approximately 13% from 1.71 ± 0.22 to 1.48 ± 0.22 m/s (P = .00006). CONCLUSIONS Our results demonstrate that liver stiffness is sensitive to altered venous blood flow, which is of clinical importance when using elastography for evaluation of portal hypertension. Furthermore, our results indicate that accurate measurement of liver stiffness requires standardized breathing conditions to rule out effects of changes in hepatic blood flow on elastographic findings.
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Affiliation(s)
- Selcan Ipek-Ugay
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Heiko Tzschätzsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen Braun
- Department of Institute of Medical Informatics, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas Fischer
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Tzschätzsch H, Sack I, Marticorena Garcia SR, Ipek-Ugay S, Braun J, Hamm B, Althoff CE. Time-Harmonic Elastography of the Liver is Sensitive to Intrahepatic Pressure Gradient and Liver Decompression after Transjugular Intrahepatic Portosystemic Shunt (TIPS) Implantation. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:595-600. [PMID: 27979668 DOI: 10.1016/j.ultrasmedbio.2016.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/13/2016] [Accepted: 10/18/2016] [Indexed: 06/06/2023]
Abstract
We investigated the correlation between hepatic venous pressure gradient (HVPG) and liver shear wave speed (SWS) measured by multi-frequency time-harmonic ultrasound elastography (THE) before and after transjugular intrahepatic portosystemic shunt (TIPS) implantation. Ten patients with ascites, cirrhotic liver disease and portal hypertension were prospectively examined with invasive HVPG measurement and THE before and after TIPS implantation. HVPG and SWS decreased after TIPS placement from 20.4 ± 2.2 mmHg to 9.8 ± 4.1 mmHg (mean ± standard deviation) and from 3.87 ± 0.54 m/s to 3.27 ± 0.44 m/s. Mean reduction HVPG was -10.6 ± 3.7 mmHg, p < 0.001; mean reduction SWS was -0.60 ± 0.29 m/s, p < 0.001. A linear correlation was observed between HVPG and SWS (R = 0.59, p = 0.0061). THE-measured SWS is a first potential direct ultrasound marker for liver decompression following TIPS in ascites-associated cirrhotic liver disease and therefore might be suitable to non-invasively detect portal hypertension.
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Affiliation(s)
- Heiko Tzschätzsch
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Selcan Ipek-Ugay
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen Braun
- Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Christian E Althoff
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
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Parker KJ, Ormachea J, Zvietcovich F, Castaneda B. Reverberant shear wave fields and estimation of tissue properties. Phys Med Biol 2017; 62:1046-1061. [DOI: 10.1088/1361-6560/aa5201] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Tzschätzsch H, Nguyen Trong M, Scheuermann T, Ipek-Ugay S, Fischer T, Schultz M, Braun J, Sack I. Two-Dimensional Time-Harmonic Elastography of the Human Liver and Spleen. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:2562-2571. [PMID: 27567061 DOI: 10.1016/j.ultrasmedbio.2016.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 07/01/2016] [Accepted: 07/02/2016] [Indexed: 06/06/2023]
Abstract
Measurement of shear wave speed of the liver and spleen by elastography is an established diagnostic procedure for the detection of hepatic fibrosis, portal hypertension and esophageal varices. However, current elastography systems are limited by the size and penetration depth of elastographic windows. In this study, 2D time-harmonic elastography is proposed for generating full field-of-view shear wave speed maps in great depth. Two-dimensional time-harmonic elastography uses external harmonic stimulation at multiple frequencies to create compound shear wave speed maps. The method is tested in a phantom with soft and stiff inclusions and used for elastography of the liver and spleen in 13 asymptomatic volunteers. Each volunteer was scanned twice to determine the sensitivity of the method to physiologic variations: first, after 2 h of fasting, and a second time, 15 min after drinking 1 L of water. The wave speed maps of the phantom clearly identified the soft and stiff inclusions, yielding values that were consistent with those from magnetic resonance elastography. In vivo wave speed values were 1.49 ± 0.11 m/s for the liver and 2.03 ± 0.15 m/s for the spleen in a lower-frequency band centered at 40 Hz and 3.15 ± 0.30 m/s for the spleen in a higher-frequency band centered at 120 Hz. After water intake, wave speed values increased by 6% in the liver (p = 0.002) and decreased in the spleen by 4% (p = 0.021, low-frequency band) and 6% (p = 0.0002, high-frequency band), suggesting the high sensitivity of the method to altered blood flow and perfusion pressure. Two-dimensional time-harmonic elastography of the liver and spleen is a promising method for measuring tissue stiffness at different states of blood flow and perfusion in a large tissue window and at great penetration depth.
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Affiliation(s)
- Heiko Tzschätzsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Tobias Scheuermann
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Selcan Ipek-Ugay
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas Fischer
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Jürgen Braun
- Institute of Medical Informatics, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Dittmann F, Tzschätzsch H, Hirsch S, Barnhill E, Braun J, Sack I, Guo J. Tomoelastography of the abdomen: Tissue mechanical properties of the liver, spleen, kidney, and pancreas from single MR elastography scans at different hydration states. Magn Reson Med 2016; 78:976-983. [DOI: 10.1002/mrm.26484] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/17/2016] [Accepted: 09/07/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Florian Dittmann
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Heiko Tzschätzsch
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Sebastian Hirsch
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Eric Barnhill
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Jürgen Braun
- Department of Medical Informatics; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Ingolf Sack
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Jing Guo
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
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The Prevalence of and Risk Factors Associated with Musculoskeletal Disorders among Sonographers in Central China: A Cross-Sectional Study. PLoS One 2016; 11:e0163903. [PMID: 27695095 PMCID: PMC5047644 DOI: 10.1371/journal.pone.0163903] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 09/18/2016] [Indexed: 11/19/2022] Open
Abstract
Objective Studies from industrialized countries show that musculoskeletal disorders (MSD) occur commonly in sonographers. However, little is known about sonographers in China, where the awareness of ergonomics and MSD, workload, and available equipment/facilities may differ. We aimed to investigate the prevalence of MSD and associated risk factors in sonographers in central China. Methods A cross-sectional survey was conducted with 381 sonographers from 14 randomly selected tertiary hospitals in Hubei province, central China. Musculoskeletal symptoms (using the Nordic Questionnaire) and risk factors (mostly derived from the Health Benefit Trust survey instrument and the Dutch Musculoskeletal Questionnaire) were recorded. Multivariate logistic regression was used to quantify associations between risk factors and MSD. Results The 12-month period prevalence of MSD was 98.3%, being highest in the neck (93.5%) and shoulder (92.2%), followed by the lower back (83.2%), wrist/hand, upper back, and elbow. Factors contributing to neck pain were psychological fatigue, shoulder abduction and trunk bend-and-twist posture. Height-adjustable tables and chairs were protective factors. Shoulder pain was associated with female sex, health status, mental stress, shoulder abduction, and trunk bend-and-twist posture. Height-adjustable chairs and the awareness of adjusting the workstation before scanning were protective factors. Elbow pain was associated with health status and height-adjustable tables. Wrist/hand pain was associated with female sex, bending the wrist, and working with obese patients. Upper back pain was associated with shoulder abduction, height-adjustable chairs, and device location. Lower back pain was associated with the number of scans performed per day, awkward postures, bending the trunk, twisting or bending the neck forward, and using a footrest. Conclusions This study suggests a high prevalence of MSD in sonographers in central China. Hence, it is necessary to improve the awareness of MSD by training, and the ergonomics of their current work environment by addressing physical workload, and psychological and equipment/facility-related factors.
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Ipek-Ugay S, Tzschätzsch H, Hudert C, Marticorena Garcia SR, Fischer T, Braun J, Althoff C, Sack I. Time Harmonic Elastography Reveals Sensitivity of Liver Stiffness to Water Ingestion. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:1289-1294. [PMID: 26971462 DOI: 10.1016/j.ultrasmedbio.2015.12.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 12/15/2015] [Accepted: 12/21/2015] [Indexed: 06/05/2023]
Abstract
The aim of the study was to test the sensitivity of liver stiffness (LS) measured by time harmonic elastography in large tissue windows to water uptake and post-prandial effects. Each subject gave written informed consent to participate in this institutional review board-approved prospective study. LS was measured by time harmonic elastography in 10 healthy volunteers pre- and post-prandially, as well as before, directly after and 2 h after drinking water. The LS-time function during water intake was measured in 14 scans over 3 h in five volunteers. LS increased by 10% (p = 0.0015) post-prandially and by 11% (p = 0.0024) after pure water ingestion, and decreased to normal values after 2 h. LS was lower after overnight fasting than after 2-h fasting (3%, p = 0.04). Over the time course, LS increased to post-water peak values 15 min after drinking 0.25 L water and remained unaffected by further ingestion of water. In conclusion, our study indicates that LS measured by time harmonic elastography represents an effective-medium property sensitive to physiologic changes in vascular load of the liver.
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Affiliation(s)
- Selcan Ipek-Ugay
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Heiko Tzschätzsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Christian Hudert
- Clinic for Pediatric Endocrinology and Diabetology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Thomas Fischer
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen Braun
- Institute of Medical Informatics, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Christian Althoff
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Tzschätzsch H, Guo J, Dittmann F, Hirsch S, Barnhill E, Jöhrens K, Braun J, Sack I. Tomoelastography by multifrequency wave number recovery from time-harmonic propagating shear waves. Med Image Anal 2016; 30:1-10. [PMID: 26845371 DOI: 10.1016/j.media.2016.01.001] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 12/23/2015] [Accepted: 01/04/2016] [Indexed: 01/02/2023]
Abstract
Palpation is one of the most sensitive, effective diagnostic practices, motivating the quantitative and spatially resolved determination of soft tissue elasticity parameters by medical ultrasound or MRI. However, this so-called elastography often suffers from limited anatomical resolution due to noise and insufficient elastic deformation, currently precluding its use as a tomographic modality on its own. We here introduce an efficient way of processing wave images acquired by multifrequency magnetic resonance elastography (MMRE), which relies on wave number reconstruction at different harmonic frequencies followed by their amplitude-weighted averaging prior to inversion. This results in compound maps of wave speed, which reveal variations in tissue elasticity in a tomographic fashion, i.e. an unmasked, slice-wise display of anatomical details at pixel-wise resolution. The method is demonstrated using MMRE data from the literature including abdominal and pelvic organs such as the liver, spleen, uterus body and uterus cervix. Even in small regions with low wave amplitudes, such as nucleus pulposus and spinal cord, elastic parameters consistent with literature values were obtained. Overall, the proposed method provides a simple and noise-robust strategy of in-plane wave analysis of MMRE data, with a pixel-wise resolution producing superior detail to MRE direct inversion methods.
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Affiliation(s)
- Heiko Tzschätzsch
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jing Guo
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Florian Dittmann
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Sebastian Hirsch
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Eric Barnhill
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Korinna Jöhrens
- Institute of Pathology, Charité - Universitätsmedizin Berlin, Germany
| | - Jürgen Braun
- Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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Dittmann F, Hirsch S, Tzschätzsch H, Guo J, Braun J, Sack I. In vivo wideband multifrequency MR elastography of the human brain and liver. Magn Reson Med 2015; 76:1116-26. [DOI: 10.1002/mrm.26006] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Revised: 08/25/2015] [Accepted: 09/12/2015] [Indexed: 01/19/2023]
Affiliation(s)
- Florian Dittmann
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Sebastian Hirsch
- Institute of Medical Informatics; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Heiko Tzschätzsch
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Jing Guo
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Jürgen Braun
- Institute of Medical Informatics; Charité - Universitätsmedizin Berlin; Berlin Germany
| | - Ingolf Sack
- Department of Radiology; Charité - Universitätsmedizin Berlin; Berlin Germany
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