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Li S, Zhou Z, Wu S, Wu W. A Review of Quantitative Ultrasound-Based Approaches to Thermometry and Ablation Zone Identification Over the Past Decade. ULTRASONIC IMAGING 2022; 44:213-228. [PMID: 35993226 DOI: 10.1177/01617346221120069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Percutaneous thermal therapy is an important clinical treatment method for some solid tumors. It is critical to use effective image visualization techniques to monitor the therapy process in real time because precise control of the therapeutic zone directly affects the prognosis of tumor treatment. Ultrasound is used in thermal therapy monitoring because of its real-time, non-invasive, non-ionizing radiation, and low-cost characteristics. This paper presents a review of nine quantitative ultrasound-based methods for thermal therapy monitoring and their advances over the last decade since 2011. These methods were analyzed and compared with respect to two applications: ultrasonic thermometry and ablation zone identification. The advantages and limitations of these methods were compared and discussed, and future developments were suggested.
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Affiliation(s)
- Sinan Li
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Zhuhuang Zhou
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Shuicai Wu
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Weiwei Wu
- College of Biomedical Engineering, Capital Medical University, Beijing, China
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2
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Li S, Tsui PH, Song S, Wu W, Zhou Z, Wu S. Detection of microwave ablation coagulation areas using ultrasound Nakagami imaging based on Gaussian pyramid decomposition: A feasibility study. ULTRASONICS 2022; 124:106758. [PMID: 35617777 DOI: 10.1016/j.ultras.2022.106758] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 03/14/2022] [Accepted: 05/07/2022] [Indexed: 06/15/2023]
Abstract
In this paper, we explored the feasibility of using ultrasound Nakagami-m parametric imaging based on Gaussian pyramid decomposition (GPD) to detect microwave ablation coagulation areas. Monte Carlo simulation and phantom simulation results demonstrated that a 2-layer GPD model was sufficient to achieve the same m parameter estimation accuracy, smoothness and resolution as 3-layer and 4-layer. The performances of GPD, moment-based estimator (MBE) and window-modulated compounding (WMC) algorithms were compared in terms of parameter estimation, smoothness, resolution and contrast-to-noise (CNR). Results showed that the m parameter estimation obtained by GPD algorithm was better than that of MBE and WMC algorithms except the small window size (27 × 5). When using a window size of >3 pulse lengths, GPD algorithm could achieve better smoothness and CNR than MBE and WMC algorithms, but there was a certain loss of axial resolution. The computation time of GPD algorithm was less than that of WMC algorithm, while about 2.24 times that of MBE algorithm. Experimental results of porcine liver microwave ablation ex vivo (n = 20) illustrated that the average areas under the operating characteristic curve (AUCs) of Nakagami mGPD, mMBE and mWMC parametric imaging and homodyned-K (HK) α and k parametric imaging to detect coagulation areas were significantly improved by polynomial approximation (PAX). Kruskal-Wallis test showed that the accuracy of coagulation area detection obtained by PAX imaging of mGPD parameter had no significant difference with that of mMBE, mWMC, HK_α and HK_k parameters. This preliminary study suggested that Nakagami imaging based on GPD algorithm may have the potential to detect microwave ablation coagulation areas.
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Affiliation(s)
- Sinan Li
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Po-Hsiang Tsui
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Institute for Radiological Research, Chang Gung University, Taoyuan, Taiwan; Division of Pediatric Gastroenterology, Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
| | - Shuang Song
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Weiwei Wu
- College of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Zhuhuang Zhou
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China.
| | - Shuicai Wu
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China.
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Wang CY, Zhou Z, Chang YH, Ho MC, Lu CM, Wu CH, Tsui PH. Ultrasound single-phase CBE imaging for monitoring radiofrequency ablation of the liver tumor: A preliminary clinical validation. Front Oncol 2022; 12:894246. [PMID: 35936752 PMCID: PMC9355697 DOI: 10.3389/fonc.2022.894246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 06/27/2022] [Indexed: 11/23/2022] Open
Abstract
Radiofrequency ablation (RFA) is an alternative treatment for early-stage hepatocellular carcinoma (HCC). The production of gas bubbles by RFA indicates threshold temperature of tissue necrosis and results in changes in backscattered energy (CBE) when ultrasound monitors RFA. In this study, ultrasound single-phase CBE imaging was used as a means of monitoring RFA of the liver tumor by analyzing the backscattering of ultrasound from gas bubbles in the liver. A total of 19 HCC patients were enrolled in the study. An ultrasound system was used during RFA to monitor the ablation process and acquire raw image data consisting of backscattered signals for single-phase CBE imaging. On the basis of single-phase CBE imaging, the area corresponding to the range of gas bubbles was compared with the tumor sizes and ablation zones estimated from computed tomography. During RFA, ultrasound single-phase CBE imaging enabled improved visualization of gas bubbles. Measured gas bubble areas by CBE were related to tumor size (the Spearman correlation coefficient rs = 0.86; p < 0.05); less dependent on the ablation zone. Approximately 95% of the data fell within the limits of agreement in Bland-Altman plots, and 58% of the data fell within the 95% CI. This study suggests that single-phase CBE imaging provides information about liver tumor size because of the abundant vessels in liver tumors that promote the generation of gas bubbles, which serve as natural contrast agents in RFAs to enhance ultrasound backscattering. Ultrasound single-phase CBE imaging may allow clinicians to determine if the required minimum RFA efficacy level is reached by assessing gas bubbles in the liver tumors.
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Affiliation(s)
- Chiao-Yin Wang
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Zhuhuang Zhou
- Department of Biomedical Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Yu-Hsuan Chang
- Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan
| | - Ming-Chih Ho
- Departments of Surgery, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei, Taiwan
- Center for Functional Image and Interventional Image, National Taiwan University, Taipei, Taiwan
- Department of Surgery, National Taiwan University Hospital Hsin-Chu Biomedical Park Branch, Hsin-Chu, Taiwan
| | - Chiu-Min Lu
- Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Horng Wu
- Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan
- Department of Radiology, College of Medicine, National Taiwan University, Taipei, Taiwan
- *Correspondence: Po-Hsiang Tsui, ; Chih-Horng Wu,
| | - Po-Hsiang Tsui
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Division of Pediatric Gastroenterology, Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
- Department of Biomedical Engineering, Chang Gung University, Taoyuan, Taiwan
- *Correspondence: Po-Hsiang Tsui, ; Chih-Horng Wu,
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4
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Wang D, Adams MS, Jones PD, Liu D, Burdette EC, Diederich CJ. High contrast ultrasonic method with multi-spatiotemporal compounding for monitoring catheter-based ultrasound thermal therapy: Development and Ex Vivo Evaluations. IEEE Trans Biomed Eng 2021; 68:3131-3141. [PMID: 33755552 DOI: 10.1109/tbme.2021.3067910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Changes in ultrasound backscatter energy (CBE) imaging can monitor thermal therapy. Catheter-based ultrasound (CBUS) can treat deep tumors with precise spatial control of energy deposition and ablation zones, of which CBE estimation can be limited by low contrast and robustness due to small or inconsistent changes in ultrasound data. This study develops a multi-spatiotemporal compounding CBE (MST-CBE) imaging approach for monitoring specific to CBUS thermal therapy. METHODS Ex vivo thermal ablations were performed with stereotactic positioning of a 180 directional CBUS applicator, temperature monitoring probes, endorectal US probe, and subsequent lesion sectioning and measurement. Five frames of raw radiofrequency data were acquired throughout in 15s intervals. Using window-by-window estimation methods, absolute and positive components of MST-CBE images at each point were obtained by the compounding ratio of squared envelope data within an increasing spatial size in each short-time window. RESULTS Compared with conventional US, Nakagami, and CBE imaging, the detection contrast and robustness quantified by tissue-modification-ratio improved by 37.24.7 (p<0.001), 37.55.2 (p<0.001), and 6.44.0 dB (p<0.05) in the MST-CBE imaging, respectively. Correlation coefficient and bias between cross-sectional dimensions of the ablation zones measured in tissue sections and estimated from MST-CBE were up to 0.91 (p<0.001) and -0.02 mm2, respectively. CONCLUSION The MST-CBE approach can monitor the detailed changes within target tissues and effectively characterize the dimensions of the ablation zone during CBUS energy deposition. SIGNIFICANCE The MST-CBE approach could be practical for improved accuracy and contrast of monitoring and evaluation for CBUS thermal therapy.
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Zhang S, Wu S, Shang S, Qin X, Jia X, Li D, Cui Z, Xu T, Niu G, Bouakaz A, Wan M. Detection and Monitoring of Thermal Lesions Induced by Microwave Ablation Using Ultrasound Imaging and Convolutional Neural Networks. IEEE J Biomed Health Inform 2020; 24:965-973. [DOI: 10.1109/jbhi.2019.2939810] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Yang K, Li Q, Liu HL, Chen CK, Huang CW, Chen JR, Tsai YW, Zhou Z, Tsui PH. Frequency-domain CBE imaging for ultrasound localization of the HIFU focal spot: a feasibility study. Sci Rep 2020; 10:5468. [PMID: 32214201 PMCID: PMC7096526 DOI: 10.1038/s41598-020-62363-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 03/10/2020] [Indexed: 11/25/2022] Open
Abstract
High-intensity focused ultrasound (HIFU) is a well-accepted tool for noninvasive thermal therapy. To control the quality of HIFU treatment, the focal spot generated in tissues must be localized. Ultrasound imaging can monitor heated regions; in particular, the change in backscattered energy (CBE) allows parametric imaging to visualize thermal information in the tissue. Conventional CBE imaging constructed in the spatial domain may be easily affected by noises when the HIFU focal spot is visualized. This study proposes frequency-domain CBE imaging to improve noise tolerance and image contrast in HIFU focal spot monitoring. Phantom experiments were performed in a temperature-controlled environment. HIFU of 2.12 MHz was applied to the phantoms, during which a clinical scanner equipped with a 3-MHz convex array transducer was used to collect raw image data consisting of backscattered signals for B-mode, spatial-, and frequency-domain CBE imaging. Concurrently, temperature changes were measured at the focal spot using a thermocouple for comparison with CBE values by calculating the correlation coefficient r. To further analyze CBE image contrast levels, a contrast factor was introduced, and an independent t-test was performed to calculate the probability value p. Experimental results showed that frequency-domain CBE imaging performed well in thermal distribution visualization, enabling quantitative detection of temperature changes. The CBE value calculated in the frequency domain also correlated strongly with that obtained using the conventional spatial-domain approach (r = 0.97). In particular, compared with the image obtained through the conventional method, the contrast of the CBE image obtained using the method based on frequency-domain analysis increased by 2.5-fold (4 dB; p < 0.05). Frequency-domain computations may constitute a new strategy when ultrasound CBE imaging is used to localize the focal spot in HIFU treatment planning.
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Affiliation(s)
- Kun Yang
- School of Microelectronics, Tianjin University, Tianjin, China
| | - Qiang Li
- School of Microelectronics, Tianjin University, Tianjin, China
| | - Hao-Li Liu
- Department of Electrical Engineering, Chang-Gung University, Taoyuan, Taiwan
| | - Chin-Kuo Chen
- Department of Otolaryngology - Head and Neck Surgery, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan
| | - Cheng-Wei Huang
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Jheng-Ru Chen
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yu-Wei Tsai
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Zhuhuang Zhou
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China.
| | - Po-Hsiang Tsui
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan. .,Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University and Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan. .,Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan.
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Besler E, Wang YC, Sahakian AV. Real-Time Radiofrequency Ablation Lesion Depth Estimation Using Multi-frequency Impedance With a Deep Neural Network and Tree-Based Ensembles. IEEE Trans Biomed Eng 2019; 67:1890-1899. [PMID: 31675310 DOI: 10.1109/tbme.2019.2950342] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Design and optimization of statistical models for use in methods for estimating radiofrequency ablation (RFA) lesion depths in soft real-time performance. METHODS Using tissue multi-frequency complex electrical impedance data collected from a low-cost embedded system, a deep neural network (NN) and tree-based ensembles (TEs) were trained for estimating the RFA lesion depth via regression. RESULTS Addition of frequency sweep data, previous depth data, and previous RF power state data boosted accuracy of the statistical models. The root mean square errors were 2 mm for NN and 0.5 mm for TEs for previous statistical models and the root mean square errors were 0.4 mm for NN and 0.04 mm for TEs for the statistical models presented in this paper. Simulation ablation performance showed a mean difference against physical measurements of 0.5 ±0.2 mm for the NN-based depth estimation method and 0.7 ±0.4 mm for the TE-based depth estimation method. CONCLUSION The results show that multi-frequency data significantly improves the depth estimation performance of the statistical models. SIGNIFICANCE The RFA lesion depth estimation methods presented in this work achieve millimeter-resolution accuracy with soft real-time performance on an ARMv7-based embedded system for potential translation to clinical RFA technologies.
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Teixeira CA, Pastrana-Chalco M, Simões RJ, Pedrosa A, von Krüger MA, Alvarenga AV, Fontes-Pereira AJ, Pereira WCA. On the Feasibility of Ultrasound Imaging Enrichment by Medium-Temperature Changes. ULTRASONIC IMAGING 2019; 41:17-34. [PMID: 30239291 DOI: 10.1177/0161734618800660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We describe the concept of a new imaging modality based on the tracking and dynamic modeling of local intensity changes (ICs) observed in conventional ultrasound images collected during a medium-temperature change. We computed the pixel-by-pixel IC from averaged B-mode images that exhibited different behaviors with varying temperature resulting from changes in the speed of sound, which consequently induce changes in the backscattered energy. Moreover, for each pixel, a first-order polynomial model was adjusted to the different temperature-dependent ICs. The representation of the polynomial angular parameter in 2D pixel space was used to obtain a parametric image. The results obtained by simulations and with real B-mode images indicated that this new ultrasound imaging modality was able to enhance the contrast and highlight structures that were poorly visible or even undetected in conventional images. A temperature change of 3°C was found to be sufficient to generate appropriate images with the proposed method. In addition, if a temperature change of 6°C was considered, the thermal dose, measured as the cumulative number of equivalent minutes at 43°C (CEM43°C), was 2.4 CEM43°C, which is a value that is considered safe according to the literature. We provide a proof-of-concept of a new imaging modality that opens new opportunities for the enhancement of ultrasound images and consequently contributes to improvements in ultrasound-based diagnoses. Our approach is based on images returned by commercial ultrasound scanners. Therefore, it can be implemented in any ultrasound system and is independent of specific ultrasound hardware and software data acquisition characteristics.
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Affiliation(s)
- C A Teixeira
- 1 Department of Informatics Engineering, Centre for Informatics and Systems (CISUC), University of Coimbra, Coimbra, Portugal
| | - M Pastrana-Chalco
- 1 Department of Informatics Engineering, Centre for Informatics and Systems (CISUC), University of Coimbra, Coimbra, Portugal
- 2 Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - R J Simões
- 1 Department of Informatics Engineering, Centre for Informatics and Systems (CISUC), University of Coimbra, Coimbra, Portugal
| | - A Pedrosa
- 1 Department of Informatics Engineering, Centre for Informatics and Systems (CISUC), University of Coimbra, Coimbra, Portugal
| | - M A von Krüger
- 2 Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - A V Alvarenga
- 3 Laboratory of Ultrasound, National Institute of Metrology, Quality and Technology (Inmetro), Rio de Janeiro, Brazil
| | - A J Fontes-Pereira
- 2 Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - W C A Pereira
- 2 Biomedical Engineering Program, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Zhang L, Li Q, Wang CY, Tsui PH. Ultrasound single-phase CBE imaging for monitoring radiofrequency ablation. Int J Hyperthermia 2018; 35:548-558. [PMID: 30354749 DOI: 10.1080/02656736.2018.1512160] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Radiofrequency (RF) ablation (RFA) is the most commonly used minimally invasive procedure for thermal ablation of liver tumors. Ultrasound not only provides real-time feedback of the electrode location for RFA guidance but also enables visualization of the tissue temperature. Changes in backscattered energy (CBE) have been widely applied to ultrasound temperature imaging for assessing thermal ablation. Pilot studies have revealed that significant shadowing features appear in CBE imaging and are caused by the electrode and RFA-induced gas bubbles. To resolve this problem, the current study proposed ultrasound single-phase CBE imaging based on positive CBE values. An in vitro model with tissue samples derived from the porcine tenderloin was used to validate the proposed method. During RFA with various electrode lengths, ultrasound scans of tissue samples were obtained using a clinical ultrasound scanner equipped with a convex array transducer of 3 MHz. Raw image data comprising 256 scan lines of backscattered RF signals were acquired for B-mode, conventional CBE, and single-phase CBE imaging by using the proposed algorithmic scheme. The ablation sizes estimated using CBE imaging and gross examinations were compared to calculate the correlation coefficient. The experimental results indicated that single-phase CBE imaging largely suppressed artificial CBE information in the shadowed region. Moreover, compared with conventional CBE imaging, single-phase CBE imaging provided a more accurate estimation of ablation sizes (the correlation coefficient was higher than 0.8).
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Affiliation(s)
- Lin Zhang
- a School of Microelectronics , Tianjin University , Tianjin , China
| | - Qiang Li
- a School of Microelectronics , Tianjin University , Tianjin , China
| | - Chiao-Yin Wang
- b Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University , Taoyuan , Taiwan.,c Department of Medical Imaging and Radiological Sciences , College of Medicine, Chang Gung University , Taoyuan , Taiwan
| | - Po-Hsiang Tsui
- c Department of Medical Imaging and Radiological Sciences , College of Medicine, Chang Gung University , Taoyuan , Taiwan.,d Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University and Chang Gung Memorial Hospital at Linkou , Taoyuan , Taiwan.,e Department of Medical Imaging and Intervention , Chang Gung Memorial Hospital at Linkou , Taoyuan , Taiwan
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10
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Zhang S, Xu R, Shang S, Han Y, Liu S, Xu T, Gu C, Zhu X, Niu G, Wan M. In vivo monitoring of microwave ablation in a porcine model using ultrasonic differential attenuation coefficient intercept imaging. Int J Hyperthermia 2018; 34:1157-1170. [DOI: 10.1080/02656736.2018.1437477] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Affiliation(s)
- Siyuan Zhang
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Ranxiang Xu
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Shaoqiang Shang
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Yuqiang Han
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Sihao Liu
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Tianqi Xu
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Chunming Gu
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Xingguang Zhu
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
- Medical Engineering Division, Beijing HuiLongGuan Hospital, Beijing, People's Republic of China
| | - Gang Niu
- Department of Radiology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, People’s Republic of China
| | - Mingxi Wan
- Department of Biomedical Engineering, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi’an Jiaotong University, Xi’an, People’s Republic of China
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11
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Abstract
Radiofrequency ablation (RFA) has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15) were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.
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12
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Liu YD, Li Q, Zhou Z, Yeah YW, Chang CC, Lee CY, Tsui PH. Adaptive ultrasound temperature imaging for monitoring radiofrequency ablation. PLoS One 2017; 12:e0182457. [PMID: 28837584 PMCID: PMC5570358 DOI: 10.1371/journal.pone.0182457] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 07/18/2017] [Indexed: 12/31/2022] Open
Abstract
Radiofrequency ablation (RFA) has been widely used as an alternative treatment modality for liver tumors. Monitoring the temperature distribution in the tissue during RFA is required to assess the thermal dosage. Ultrasound temperature imaging based on the detection of echo time shifts has received the most attention in the past decade. The coefficient k, connecting the temperature change and the echo time shift, is a medium-dependent parameter used to describe the confounding effects of changes in the speed of sound and thermal expansion as temperature increases. The current algorithm of temperature estimate based on echo time shift detection typically uses a constant k, resulting in estimation errors when ablation temperatures are higher than 50°C. This study proposes an adaptive-k algorithm that enables the automatic adjustment of the coefficient k during ultrasound temperature monitoring of RFA. To verify the proposed algorithm, RFA experiments on in vitro porcine liver samples (total n = 15) were performed using ablation powers of 10, 15, and 20 W. During RFA, a clinical ultrasound system equipped with a 7.5-MHz linear transducer was used to collect backscattered signals for ultrasound temperature imaging using the constant- and adaptive-k algorithms. Concurrently, an infrared imaging system and thermocouples were used to measure surface temperature distribution of the sample and internal ablation temperatures for comparisons with ultrasound estimates. Experimental results demonstrated that the proposed adaptive-k method improved the performance in visualizing the temperature distribution. In particular, the estimation errors were also reduced even when the temperature of the tissue is higher than 50°C. The proposed adaptive-k ultrasound temperature imaging strategy has potential to serve as a thermal dosage evaluation tool for monitoring high-temperature RFA.
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Affiliation(s)
- Yi-Da Liu
- School of Electronic Information Engineering, Tianjin University, Tianjin, China
| | - Qiang Li
- School of Electronic Information Engineering, Tianjin University, Tianjin, China
| | - Zhuhuang Zhou
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
- Faculty of Information Technology, Beijing University of Technology, Beijing, China
| | - Yao-Wen Yeah
- Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
| | - Chien-Cheng Chang
- Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
- * E-mail: (PHT); (CCC)
| | - Chia-Yen Lee
- Department of Electrical Engineering, National United University, Miao-Li, Taiwan
| | - Po-Hsiang Tsui
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University and Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
- * E-mail: (PHT); (CCC)
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13
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Pasternak M, Samset E, D'hooge J, Haugen GU. Temperature monitoring by channel data delays: Feasibility based on estimated delays magnitude for cardiac ablation. ULTRASONICS 2017; 77:32-37. [PMID: 28167318 DOI: 10.1016/j.ultras.2017.01.011] [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: 06/24/2016] [Revised: 01/05/2017] [Accepted: 01/12/2017] [Indexed: 06/06/2023]
Abstract
Ultrasound thermometry is based on measuring tissue temperature by its impact on ultrasound wave propagation. This study focuses on the use of transducer array channel data (not beamformed) and examines how a layer of increased velocity (heat induced) affects the travel-times of the ultrasound backscatter signal. Based on geometric considerations, a new equation was derived for the change in time delay as a function of temperature change. The resulting expression provides insight into the key factors that link change in temperature to change in travel time. It shows that velocity enters in combination with heating geometry: complementary information is needed to compute velocity from the changes in travel time. Using the bio-heat equation as a second source of information in the derived expressions, the feasibility of monitoring the temperature increase during cardiac ablation therapy using channel data was investigated. For an intra-cardiac (ICE) probe, using this "time delay error approach" would not be feasible, while for a trans-esophageal array transducer (TEE) transducer it might be feasible.
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Affiliation(s)
- Margot Pasternak
- GE Vingmed Ultrasound, Horten, Norway; KU Leuven, Leuven, Belgium.
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14
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Zhang S, Han Y, Zhu X, Shang S, Huang G, Zhang L, Niu G, Wang S, He X, Wan M. Feasibility of Using Ultrasonic Nakagami Imaging for Monitoring Microwave-Induced Thermal Lesion in Ex Vivo Porcine Liver. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:482-493. [PMID: 27894833 DOI: 10.1016/j.ultrasmedbio.2016.10.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/05/2016] [Accepted: 10/13/2016] [Indexed: 06/06/2023]
Abstract
The feasibility of using ultrasonic Nakagami imaging to evaluate thermal lesions induced by microwave ablation (MWA) in ex vivo porcine liver was explored. Dynamic changes in echo amplitudes and Nakagami parameters in the region of the MWA-induced thermal lesion, as well as the contrast-to-noise ratio (CNR) between the MWA-induced thermal lesion and the surrounding normal tissue, were calculated simultaneously during the MWA procedure. After MWA exposure, a bright hyper-echoic region appeared in ultrasonic B-mode and Nakagami parameter images as an indicator of the thermal lesion. Mean values of the Nakagami parameter in the thermal lesion region increased to 0.58, 0.71 and 0.91 after 1, 3 and 5 min of MVA. There were no significant differences in envelope amplitudes in the thermal lesion region among ultrasonic B-mode images obtained after different durations of MWA. Unlike ultrasonic B-mode images, Nakagami images were less affected by the shadow effect in monitoring of MWA exposure, and a fairly complete hyper-echoic region was observed in the Nakagami image. The mean value of the Nakagami parameter increased from approximately 0.47 to 0.82 during MWA exposure. At the end of the postablation stage, the mean value of the Nakagami parameter decreased to 0.55 and was higher than that before MWA exposure. CNR values calculated for Nakagami parameter images increased from 0.13 to approximately 0.61 during MWA and then decreased to 0.26 at the end of the post-ablation stage. The corresponding CNR values calculated for ultrasonic B-mode images were 0.24, 0.42 and 0.17. This preliminary study on ex vivo porcine liver suggested that Nakagami imaging have potential use in evaluating the formation of MWA-induced thermal lesions. Further in vivo studies are needed to evaluate the potential application.
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Affiliation(s)
- Siyuan Zhang
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Yuqiang Han
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Xingguang Zhu
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Shaoqiang Shang
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Guojing Huang
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Lei Zhang
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Gang Niu
- Department of Radiology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Supin Wang
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China
| | - Xijing He
- Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Mingxi Wan
- Key Laboratory of Biomedical Information Engineering, Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, China.
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15
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Hsiao YS, Deng CX. Calibration and Evaluation of Ultrasound Thermography Using Infrared Imaging. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:503-17. [PMID: 26547634 PMCID: PMC4698082 DOI: 10.1016/j.ultrasmedbio.2015.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 08/24/2015] [Accepted: 09/23/2015] [Indexed: 05/11/2023]
Abstract
Real-time monitoring of the spatiotemporal evolution of tissue temperature is important to ensure safe and effective treatment in thermal therapies including hyperthermia and thermal ablation. Ultrasound thermography has been proposed as a non-invasive technique for temperature measurement, and accurate calibration of the temperature-dependent ultrasound signal changes against temperature is required. Here we report a method that uses infrared thermography for calibration and validation of ultrasound thermography. Using phantoms and cardiac tissue specimens subjected to high-intensity focused ultrasound heating, we simultaneously acquired ultrasound and infrared imaging data from the same surface plane of a sample. The commonly used echo time shift-based method was chosen to compute ultrasound thermometry. We first correlated the ultrasound echo time shifts with infrared-measured temperatures for material-dependent calibration and found that the calibration coefficient was positive for fat-mimicking phantom (1.49 ± 0.27) but negative for tissue-mimicking phantom (-0.59 ± 0.08) and cardiac tissue (-0.69 ± 0.18°C-mm/ns). We then obtained the estimation error of the ultrasound thermometry by comparing against the infrared-measured temperature and revealed that the error increased with decreased size of the heated region. Consistent with previous findings, the echo time shifts were no longer linearly dependent on temperature beyond 45°C-50°C in cardiac tissues. Unlike previous studies in which thermocouples or water bath techniques were used to evaluate the performance of ultrasound thermography, our results indicate that high-resolution infrared thermography is a useful tool that can be applied to evaluate and understand the limitations of ultrasound thermography methods.
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Affiliation(s)
- Yi-Sing Hsiao
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Cheri X Deng
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA.
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16
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Abstract
In this review we present the current status of ultrasound thermometry and ablation monitoring, with emphasis on the diverse approaches published in the literature and with an eye on which methods are closest to clinical reality. It is hoped that this review will serve as a guide to the expansion of sonographic methods for treatment monitoring and thermometry since the last brief review in 2007.
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Affiliation(s)
- Matthew A. Lewis
- Department of Radiology, UT Southwestern Medical Center at Dallas
| | - Robert M. Staruch
- Department of Radiology, UT Southwestern Medical Center at Dallas
- Ultrasound Imaging & Interventions, Philips Research North America
| | - Rajiv Chopra
- Department of Radiology, UT Southwestern Medical Center at Dallas
- Advanced Imaging Research Center, UT Southwestern Medical Center at Dallas
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17
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Zhou Z, Wu W, Wu S, Xia J, Wang CY, Yang C, Lin CC, Tsui PH. A survey of ultrasound elastography approaches to percutaneous ablation monitoring. Proc Inst Mech Eng H 2014; 228:1069-82. [DOI: 10.1177/0954411914554438] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Percutaneous thermal ablation has been widely used as a minimally invasive treatment for tumors. Treatment monitoring is essential for preventing complications while ensuring treatment efficacy. Mechanical testing measurements on tissue reveal that tissue stiffness increases with temperature and ablation duration. Different types of imaging methods can be used to monitor ablation procedures, including temperature or thermal strain imaging, strain imaging, modulus imaging, and shear modulus imaging. Ultrasound elastography demonstrates the potential to become the primary imaging modality for monitoring percutaneous ablation. This review briefly presented the state-of-the-art ultrasound elastography approaches for monitoring radiofrequency ablation and microwave ablation. These techniques were divided into four groups: quasi-static elastography, acoustic radiation force elastography, sonoelastography, and applicator motion elastography. Their advantages and limitations were compared and discussed. Future developments were proposed with respect to heat-induced bubbles, tissue inhomogeneities, respiratory motion, three-dimensional monitoring, multi-parametric monitoring, real-time monitoring, experimental data center for percutaneous ablation, and microwave ablation monitoring.
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Affiliation(s)
- Zhuhuang Zhou
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
| | - Weiwei Wu
- College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing, China
| | - Shuicai Wu
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
| | - Jingjing Xia
- School of Electronic Information Engineering, Tianjin University, Tianjin, China
| | - Chiao-Yin Wang
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chunlan Yang
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
| | - Chung-Chih Lin
- Department of Computer Science and Information Engineering, Chang Gung University, Taoyuan, Taiwan
| | - Po-Hsiang Tsui
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Medical Image Research Center, Institute for Radiological Research, Chang Gung University, Taoyuan, Taiwan
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18
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Teixeira CA, Alvarenga AV, Cortela G, von Krüger MA, Pereira WCA. Feasibility of non-invasive temperature estimation by the assessment of the average gray-level content of B-mode images. ULTRASONICS 2014; 54:1692-1702. [PMID: 24630851 DOI: 10.1016/j.ultras.2014.02.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 12/12/2013] [Accepted: 02/19/2014] [Indexed: 06/03/2023]
Abstract
This paper assesses the potential of the average gray-level (AVGL) from ultrasonographic (B-mode) images to estimate temperature changes in time and space in a non-invasive way. Experiments were conducted involving a homogeneous bovine muscle sample, and temperature variations were induced by an automatic temperature regulated water bath, and by therapeutic ultrasound. B-mode images and temperatures were recorded simultaneously. After data collection, regions of interest (ROIs) were defined, and the average gray-level variation computed. For the selected ROIs, the AVGL-Temperature relation were determined and studied. Based on uniformly distributed image partitions, two-dimensional temperature maps were developed for homogeneous regions. The color-coded temperature estimates were first obtained from an AVGL-Temperature relation extracted from a specific partition (where temperature was independently measured by a thermocouple), and then extended to the other partitions. This procedure aimed to analyze the AVGL sensitivity to changes not only in time but also in space. Linear and quadratic relations were obtained depending on the heating modality. We found that the AVGL-Temperature relation is reproducible over successive heating and cooling cycles. One important result was that the AVGL-Temperature relations extracted from one region might be used to estimate temperature in other regions (errors inferior to 0.5 °C) when therapeutic ultrasound was applied as a heating source. Based on this result, two-dimensional temperature maps were developed when the samples were heated in the water bath and also by therapeutic ultrasound. The maps were obtained based on a linear relation for the water bath heating, and based on a quadratic model for the therapeutic ultrasound heating. The maps for the water bath experiment reproduce an acceptable heating/cooling pattern, and for the therapeutic ultrasound heating experiment, the maps seem to reproduce temperature profiles consistent with the pressure field of the transducer, and in agreement with temperature maps developed by COMSOL®MultiPhysics simulations.
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Affiliation(s)
- C A Teixeira
- Centro de Informática e Sistemas, Polo II, Departamento de Engenharia Informática, Pinhal de Marrocos, Universidade de Coimbra, 3030-290 Coimbra, Portugal.
| | - A V Alvarenga
- Laboratory of Ultrasound/National Institute of Metrology, Standardization and Industrial Quality (Inmetro), Duque de Caxias, Brazil
| | - G Cortela
- Laboratorio de Acústica Ultrasonora, Facultad de Ciencias, Universidad de la República, Iguá 4225, Montevideo 11400, Uruguay
| | - M A von Krüger
- Biomedical Eng. Program/COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - W C A Pereira
- Biomedical Eng. Program/COPPE, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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19
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An approach for the visualization of temperature distribution in tissues according to changes in ultrasonic backscattered energy. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2013; 2013:682827. [PMID: 24260041 PMCID: PMC3821909 DOI: 10.1155/2013/682827] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 09/10/2013] [Indexed: 12/05/2022]
Abstract
Previous studies developed ultrasound temperature-imaging methods based on changes in backscattered energy (CBE) to monitor variations in temperature during hyperthermia. In conventional CBE imaging, tracking and compensation of the echo shift due to temperature increase need to be done. Moreover, the CBE image does not enable visualization of the temperature distribution in tissues during nonuniform heating, which limits its clinical application in guidance of tissue ablation treatment. In this study, we investigated a CBE imaging method based on the sliding window technique and the polynomial approximation of the integrated CBE (ICBEpa image) to overcome the difficulties of conventional CBE imaging. We conducted experiments with tissue samples of pork tenderloin ablated by microwave irradiation to validate the feasibility of the proposed method. During ablation, the raw backscattered signals were acquired using an ultrasound scanner for B-mode and ICBEpa imaging. The experimental results showed that the proposed ICBEpa image can visualize the temperature distribution in a tissue with a very good contrast. Moreover, tracking and compensation of the echo shift were not necessary when using the ICBEpa image to visualize the temperature profile. The experimental findings suggested that the ICBEpa image, a new CBE imaging method, has a great potential in CBE-based imaging of hyperthermia and other thermal therapies.
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20
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Zhou Z, Sheng L, Wu S, Yang C, Zeng Y. Ultrasonic evaluation of microwave-induced thermal lesions based on wavelet analysis of mean scatterer spacing. ULTRASONICS 2013; 53:1325-1331. [PMID: 23648210 DOI: 10.1016/j.ultras.2013.03.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 03/30/2013] [Accepted: 03/31/2013] [Indexed: 06/02/2023]
Abstract
The microwave ablation has become an important manner for tumor treatment. In this paper, we proposed a new method for evaluation of microwave-induced thermal lesions using the wavelet analysis of the mean scatterer spacing (MSS). First, the ultrasonic radiofrequency (RF) data of normal and coagulated porcine liver tissues was collected through the temperature-controlled water bath heating experiments. The convex array ultrasound probe with a center frequency of 3.5 MHz was used. Second, the wavelet analysis was used to compute the MSS of normal and coagulated porcine liver tissues, respectively. Finally, the microwave-induced thermal lesions were detected based on the differences in the MSS between normal tissues and thermal lesions. Eighteen cases of microwave ablation experiments and 20 cases of water bath heating experiments were conducted on fresh porcine liver samples. The MSS of normal porcine liver tissues was 1.15±0.12 mm, and the MSS of coagulated porcine liver tissues was 0.93±0.07 mm. Six cases of thermal lesions were compared between the MSS-detected area and the caliper-measured area, and the MSS-detected area had an error of (13.55±5.29) %. The experimental results indicated that the proposed method could be used in preliminary detection and evaluation of microwave-induced thermal lesions.
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Affiliation(s)
- Zhuhuang Zhou
- College of Life Science and Bioengineering, Beijing University of Technology, Beijing, China
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21
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Wang CY, Geng X, Yeh TS, Liu HL, Tsui PH. Monitoring radiofrequency ablation with ultrasound Nakagami imaging. Med Phys 2013; 40:072901. [DOI: 10.1118/1.4808115] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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