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Lascaud J, Parodi K. On the potential biological impact of radiation-induced acoustic emissions during ultra-high dose rate electron radiotherapy: a preliminary study. Phys Med Biol 2023; 68. [PMID: 36749987 DOI: 10.1088/1361-6560/acb9ce] [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: 12/05/2022] [Accepted: 02/07/2023] [Indexed: 02/09/2023]
Abstract
Ionizing radiation pulses delivered at ultra-high dose rates in emerging FLASH radiotherapy can result in high-intensity low-frequency thermoacoustic emissions that may have a biological impact. This study aims at providing insights into the thermoacoustic emissions expected during FLASH radiotherapy and their likelihood of inducing acoustic cavitation. The characteristics of acoustic waves induced by the energy deposition of a pulsed electron beam similar to previous pre-clinical FLASH radiotherapy studies and their propagation in murine head-like phantoms are investigated in-silico. The results show that the generated pressures are sufficient to produce acoustic cavitation due to resonance in the irradiated object. It suggests that thermoacoustics may, in some irradiation scenarios, contribute to the widely misunderstood FLASH effect or cause adverse effects if not taken into account at the treatment planning stage.
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Affiliation(s)
- Julie Lascaud
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Katia Parodi
- Department of Medical Physics, Ludwig-Maximilians-Universität München, Munich, Germany
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Xu H, Li S, Cao L, Zhu X, Xue Y, Huang Y, Hua Y. The application of a novel hydrodynamic cavitation device to debride intra-articular monosodium urate crystals. BMC Surg 2023; 23:35. [PMID: 36765342 PMCID: PMC9912527 DOI: 10.1186/s12893-023-01929-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 02/01/2023] [Indexed: 02/12/2023] Open
Abstract
INTRODUCTION Efficient and complete debridement of intra-articular deposits of monosodium urate crystals is rarely achieved by existing arthroscopic tools such as shavers or radiofrequency ablation, while cavitation technology represents a prospective solution for the non-invasive clearance of adhesions at intra-articular interfaces. METHODS Simulation modeling was conducted to identify the optimal parameters for the device, including nozzle diameters and jet pressures. Gouty arthritis model was established in twelve rats that were equally and randomly allocated into a cavitation debridement group or a curette debridement group. A direct injection nozzle was designed and then applied on animal model to verify the effect of the cavitation jet device on the removal of crystal deposits. Image analysis was performed to evaluate the clearance efficiency of the cavitation device and the pathological features of surrounding tissue were collected in all groups. RESULTS To maximize cavitation with the practical requirements of the operation, an experimental rig was applied, including a 1 mm direct injection nozzle with a jet pressure of 2.0 MPa at a distance of 20 mm and a nitrogen bottle as high-pressure gas source. With regards to feasibility of the device, the clearance rates in the cavitation group were over 97% and were significantly different from the control group. Pathological examination showed that the deposition of monosodium urate crystals was removed completely while preserving the normal structure of the collagen fibers. CONCLUSIONS We developed a promising surgical device to efficiently remove intra-articular deposits of monosodium urate crystals. The feasibility and safety profile of the device were also verified in a rat model. Our findings provide a non-invasive method for the intraoperative treatment of refractory gouty arthritis.
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Affiliation(s)
- Hanlin Xu
- grid.411405.50000 0004 1757 8861Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Shengkun Li
- grid.411405.50000 0004 1757 8861Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Ling Cao
- grid.411405.50000 0004 1757 8861Department of Rheumatology, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Xiaoxia Zhu
- grid.411405.50000 0004 1757 8861Department of Rheumatology, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Yu Xue
- grid.411405.50000 0004 1757 8861Department of Rheumatology, Huashan Hospital, Fudan University, Shanghai, 200040 China
| | - Yu Huang
- State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Institute of Vibration Shock and Noise, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai, 200240, China.
| | - Yinghui Hua
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, 200040, China.
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Seyedmirzaei Sarraf S, Rokhsar Talabazar F, Namli I, Maleki M, Sheibani Aghdam A, Gharib G, Grishenkov D, Ghorbani M, Koşar A. Fundamentals, biomedical applications and future potential of micro-scale cavitation-a review. LAB ON A CHIP 2022; 22:2237-2258. [PMID: 35531747 DOI: 10.1039/d2lc00169a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Thanks to the developments in the area of microfluidics, the cavitation-on-a-chip concept enabled researchers to control and closely monitor the cavitation phenomenon in micro-scale. In contrast to conventional scale, where cavitation bubbles are hard to be steered and manipulated, lab-on-a-chip devices provide suitable platforms to conduct smart experiments and design reliable devices to carefully harness the collapse energy of cavitation bubbles in different bio-related and industrial applications. However, bubble behavior deviates to some extent when confined to micro-scale geometries in comparison to macro-scale. Therefore, fundamentals of micro-scale cavitation deserve in-depth investigations. In this review, first we discussed the physics and fundamentals of cavitation induced by tension-based as well as energy deposition-based methods within microfluidic devices and discussed the similarities and differences in micro and macro-scale cavitation. We then covered and discussed recent developments in bio-related applications of micro-scale cavitation chips. Lastly, current challenges and future research directions towards the implementation of micro-scale cavitation phenomenon to emerging applications are presented.
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Affiliation(s)
- Seyedali Seyedmirzaei Sarraf
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
| | - Farzad Rokhsar Talabazar
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
| | - Ilayda Namli
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
| | - Mohammadamin Maleki
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
| | - Araz Sheibani Aghdam
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
| | - Ghazaleh Gharib
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
- Center of Excellence for Functional Surfaces and Interfaces for Nano-Diagnostics (EFSUN), Sabanci University, Orhanli, 34956, Tuzla, Istanbul, Turkey
| | - Dmitry Grishenkov
- Department of Biomedical Engineering and Health Systems, KTH Royal Institute of Technology, SE-141 57 Stockholm, Sweden
| | - Morteza Ghorbani
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
- Center of Excellence for Functional Surfaces and Interfaces for Nano-Diagnostics (EFSUN), Sabanci University, Orhanli, 34956, Tuzla, Istanbul, Turkey
| | - Ali Koşar
- Faculty of Engineering and Natural Science, Sabanci University, 34956 Tuzla, Istanbul, Turkey.
- Sabanci University Nanotechnology Research and Application Center, 34956 Tuzla, Istanbul, Turkey
- Center of Excellence for Functional Surfaces and Interfaces for Nano-Diagnostics (EFSUN), Sabanci University, Orhanli, 34956, Tuzla, Istanbul, Turkey
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Moghimnezhad M, Shahidian A, Andayesh M. Multiphysics Analysis of Ultrasonic Shock Wave Lithotripsy and Side Effects on Surrounding Tissues. J Biomed Phys Eng 2021; 11:701-712. [PMID: 34904067 PMCID: PMC8649164 DOI: 10.31661/jbpe.v0i0.1182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Accepted: 07/08/2019] [Indexed: 11/16/2022]
Abstract
Background: Today, the most common method for kidney stone therapy is extracorporeal shock wave lithotripsy. Current research is a numerical simulation of kidney stone fragmentation via ultrasonic shock waves.
Most numerical studies in lithotripsy have been carried out using the elasticity or energy method and neglected the dissipation phenomenon. In the current study,
it is solved by not only the linear acoustics equation, but also the Westervelt acoustics equation which nonlinearity and dissipation are involved. Objective: This study is to compare two methods for simulation of shock wave lithotripsy, clarifying the effect of shock wave profiles and stones’ material, and investigating side effects on surrounding tissues Material and Methods: Computational study is done using COMSOL Multiphysics, commercial software based on the finite element method. Nonlinear governing equations of acoustics,
elasticity and bioheat-transfer are coupled and solved. Results: A decrease in the rise time of shock wave leads to increase the produced acoustic pressure and enlarge focus region. The shock wave damages kidney tissues in both linear and nonlinear
simulation but the damage due to high temperature is very negligible compared to the High Intensity Focused Ultrasound (HIFU). Conclusion: Disaffiliation of wave nonlinearity causes a high incompatibility with reality. Stone’s material is an important factor, affecting the fragmentation
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Affiliation(s)
- Mahdi Moghimnezhad
- MSc, Department of Mechanical Engineering, K. N . Toosi University of Technology, Tehran, Iran
| | - Azadeh Shahidian
- PhD, Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran
| | - Mohammad Andayesh
- BSc, Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran, Iran
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Abbasiasl T, Sutova H, Niazi S, Celebi G, Karavelioglu Z, Kirabali U, Yilmaz A, Uvet H, Kutlu O, Ekici S, Ghorbani M, Kosar A. A Flexible Cystoscope Based on Hydrodynamic Cavitation for Tumor Tissue Ablation. IEEE Trans Biomed Eng 2021; 69:513-524. [PMID: 34329154 DOI: 10.1109/tbme.2021.3100542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Hydrodynamic cavitation is characterized by the formation of bubbles inside a flow due to local reduction of pressure below the saturation vapor pressure. The resulting growth and violent collapse of bubbles lead to a huge amount of released energy. This energy can be implemented in different fields such as heat transfer enhancement, wastewater treatment and chemical reactions. In this study, a cystoscope based on small scale hydrodynamic cavitation was designed and fabricated to exploit the destructive energy of cavitation bubbles for treatment of tumor tissues. The developed device is equipped with a control system, which regulates the movement of the cystoscope in different directions. According to our experiments, the fabricated cystoscope was able to locate the target and expose cavitating flow to the target continuously and accurately. The designed cavitation probe embedded into the cystoscope caused a significant damage to prostate cancer and bladder cancer tissues within less than 15 minutes. The results of our experiments showed that the cavitation probe could be easily coupled with endoscopic devices because of its small diameter. We successfully integrated a biomedical camera, a suction tube, tendon cables, and the cavitation probe into a 6.7 mm diameter cystoscope, which could be controlled smoothly and accurately via a control system. The developed device is considered as a mechanical ablation therapy, can be a solid alternative for minimally invasive tissue ablation methods such as radiofrequency (RF) and laser ablation, and could have lower side effects compared to ultrasound therapy and cryoablation.
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Zhan S, Duan H, Pan L, Tu J, Jia D, Yang T, Li J. Molecular dynamics simulation of shock-induced microscopic bubble collapse. Phys Chem Chem Phys 2021; 23:8446-8455. [PMID: 33876008 DOI: 10.1039/d1cp00406a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Shock waves and micro-jets generated during the process of bubble collapse lead to cavitation damage on the surface of materials in hydraulic machinery equipment parts, which is attention. However, research on the dynamics of bubble collapse is still unclear. In this work, molecular dynamics (MD) simulations are used to study the compression and collapse processes of microscopic bubbles under the impact of different velocities for water molecules. The velocities of the shock wave, time of bubble collapse and shock pressure of collapse were obtained. Results showed that higher the impact velocity, shorter is the time of bubble collapse and the higher velocity of the micro-jet. After the bubble collapse, the micro-jet will form secondary water hammer shocks and a greater shock pressure. The water structure appears to undergo a phase change (ice-VII structure) when the velocity of water molecules is 1.0 km s-1. The shock induces the bubble collapse and the micro-jet significantly increases the chemical activity of water molecules; the degree of ionization of water molecules increases with the shock velocity. In addition, the Hugoniot curve of the shock velocity obtained by molecular dynamics simulations are in good agreement with the experimental data.
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Affiliation(s)
- Shengpeng Zhan
- State Key Laboratory of Special Surface Protection Materials and Application Technology, Wuhan Research Institute of Materials Protection, Wuhan 430030, China.
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Vesipa R, Paissoni E, Manes C, Ridolfi L. Dynamics of bubbles under stochastic pressure forcing. Phys Rev E 2021; 103:023108. [PMID: 33736035 DOI: 10.1103/physreve.103.023108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 01/28/2021] [Indexed: 11/07/2022]
Abstract
Several studies have investigated the dynamics of a single spherical bubble at rest under a nonstationary pressure forcing. However, attention has almost always been focused on periodic pressure oscillations, neglecting the case of stochastic forcing. This fact is quite surprising, as random pressure fluctuations are widespread in many applications involving bubbles (e.g., hydrodynamic cavitation in turbulent flows or bubble dynamics in acoustic cavitation), and noise, in general, is known to induce a variety of counterintuitive phenomena in nonlinear dynamical systems such as bubble oscillators. To shed light on this unexplored topic, here we study bubble dynamics as described by the Keller-Miksis equation, under a pressure forcing described by a Gaussian colored noise modeled as an Ornstein-Uhlenbeck process. Results indicate that, depending on noise intensity, bubbles display two peculiar behaviors: when intensity is low, the fluctuating pressure forcing mainly excites the free oscillations of the bubble, and the bubble's radius undergoes small amplitude oscillations with a rather regular periodicity. Differently, high noise intensity induces chaotic bubble dynamics, whereby nonlinear effects are exacerbated and the bubble behaves as an amplifier of the external random forcing.
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Affiliation(s)
- Riccardo Vesipa
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Eleonora Paissoni
- Cranfield Water Science Institute, Cranfield University, Bedfordshire MK43 0AL, United Kingdom
| | - Costantino Manes
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Luca Ridolfi
- Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino, Italy
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Delgado S, Curiel L, Pichardo S. Steering single-element lead zirconate titanate ultrasound transducers using biaxial driving. ULTRASONICS 2021; 110:106241. [PMID: 32916381 DOI: 10.1016/j.ultras.2020.106241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/09/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Previous work has shown that biaxial driving using two phase-offset orthogonal electric fields (propagation and lateral) improves the efficiency of ferroelectric materials by reducing coercivity and, hence, energy dissipation. In the current investigation, we demonstrated the capability of the biaxial method to steer ultrasound waves in single-element piezoceramic transducers made of prismatic lead zirconate titanate (PZT). We conducted finite element analysis simulations for 133 kHz (model 1) and 470 kHz biaxial (model 2) transducers models. We performed experimental validation with biaxially driven single-element transducers (n = 3) operating at an average frequency of 131 kHz with the same characteristics as model 1. For both models, we found non-symmetric steering that was a function of both the phase and power of the second electric field. At a constant electrical power (1 W) on the propagation electrodes, simulations for the 133 kHz model predicted maximal steering of 10.3°, 22.6°, and 30.9° for lateral electrode powers of 0.1 W, 0.5 W, and 1.0 W, respectively. Experimentally, for model 1, the maximal steering was 11.7° ± 1.9°, 23.5° ± 3.5°, and 30.2° ± 4.4° for the lateral electrode powers of 0.1 W, 0.5 W, and 1.0 W, respectively. Simulations for the 470 kHz model predicted maximal steering of 8.8°, 16.1°, and 27° for lateral electrode powers of 0.1 W, 0.5 W, and 1.0 W, respectively. Simulations showed that the cause of the steering asymmetry was a non-uniform shear deformation associated with the slightly off-resonance lateral electric field driving frequency. This is the first demonstration of ultrasound steering using a single-element transducer, which can have important applications for ultrasound focusing with phased arrays.
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Affiliation(s)
- Sagid Delgado
- Department of Electrical and Computer Engineering, Lakehead University, Canada.
| | - Laura Curiel
- Department of Electrical and Computer Engineering, University of Calgary, Canada.
| | - Samuel Pichardo
- Departments of Radiology and Clinical Neurosciences, University of Calgary, Canada.
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Shi A, Lundt J, Deng Z, Macoskey J, Gurm H, Owens G, Zhang X, Hall TL, Xu Z. Integrated Histotripsy and Bubble Coalescence Transducer for Thrombolysis. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:2697-2709. [PMID: 30279032 PMCID: PMC6215517 DOI: 10.1016/j.ultrasmedbio.2018.08.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/16/2018] [Accepted: 08/17/2018] [Indexed: 05/04/2023]
Abstract
After the collapse of a cavitation bubble cloud, residual microbubbles can persist for up to seconds and function as weak cavitation nuclei for subsequent pulses in a phenomenon known as cavitation memory effect. In histotripsy, the cavitation memory effect can cause bubble clouds to repeatedly form at the same discrete set of sites. This effect limits the efficacy of histotripsy-based tissue fractionation. Our previous studies have indicated that low-amplitude bubble-coalescing (BC) ultrasound sequences interleaved with high-amplitude histotripsy pulses can coalesce the residual bubbles into one large bubble quickly. This reduces the cavitation memory effect and may increase treatment efficacy. Histotripsy has been investigated for thrombolysis by breaking up clots into debris smaller than red blood cells. However, this treatment has low efficacy for aged or retracted clots. In this study, we investigate the use of histotripsy with BC to improve the efficacy of treatment of retracted clots. An integrated histotripsy and bubble-coalescing (HBC) transducer system with specialized electronic driving system was built in-house. One high-amplitude (32 MPa), one-cycle histotripsy pulse followed by 36 low-amplitude (2.4 MPa), one-cycle BC pulses formed one HBC sequence. Results indicate that HBC sequences successfully generated a flow channel through the retracted clots at scan speeds of 0.2-0.5 mm/s. The channel size created using the HBC sequence was 128% to 480% larger than that created using histotripsy alone. The clot debris particles generated during HBC treatments were within the tolerable range. These results illustrate the concept that BC improves the treatment efficacy of histotripsy thrombolysis for retracted clots.
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Affiliation(s)
- Aiwei Shi
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA.
| | - Jonathan Lundt
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Zilin Deng
- Department of Biomedical Engineering, Beihang University, Beijing, China
| | - Jonathan Macoskey
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Hitinder Gurm
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Gabe Owens
- Division of Pediatric Cardiology, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, USA
| | - Xi Zhang
- Fitbit Corporation, San Francisco, California, USA
| | - Timothy L Hall
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Zhen Xu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA; Division of Pediatric Cardiology, Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, Michigan, USA
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Choi MJ, Kang G, Huh JS. Geometrical characterization of the cavitation bubble clouds produced by a clinical shock wave device. Biomed Eng Lett 2017; 7:143-151. [PMID: 30603161 DOI: 10.1007/s13534-017-0017-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/29/2017] [Accepted: 02/05/2017] [Indexed: 11/27/2022] Open
Abstract
This study was to optically visualize the cavitation bubbles produced by a clinical shock wave and to look into their geometric features of the resulting cavitation bubbles in relation to the driving shock wave field. A clinical shock wave therapeutic system was taken for shock wave production. The shock wave induced cavitation bubbles were captured by a professional camera under the illumination of a micro-pulse LED light. The light exposure was set to last for the whole life time of bubbles from formation to subsequent collapses. It was shown that the cavitation bubbles appeared mostly in the vicinity of the focus. The bubbles became more and larger as approaching to the focus. The cavitation bubbles formed jet streams which became enlarged (stronger) as the shock wave device output setting increased. The bubble cloud boundary was reasonably fitted to an elongated ellipsoid characteristically similar to the acoustic focal area. The bubble clouds were enlarged as the output setting increased. The geometric features of the cavitation bubbles characteristically similar to those of the focusing acoustic field have potential to provide the therapeutic focal information without time consuming hydrophone measurements of the shock wave field causing damages of the expensive sensor. The present study is limited to the static afterimages of the cavitation bubbles and investigation including the bubble dynamics is suggested to deliver the more realistic therapeutic area of the shock wave therapy.
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Affiliation(s)
- Min Joo Choi
- 1Department of Medicine, School of Medicine, Jeju National University, 102 Jejudaehakno, Jeju-Si, Jeju Special Self-Governing Province 63294 Republic of Korea.,2Interdisciplinary Postgraduate Program in Biomedical Engineering, Jeju National University, 102 Jejudaehakno, Jeju-Si, Jeju Special Self-Governing Province 63294 Republic of Korea
| | - Gwansuk Kang
- 2Interdisciplinary Postgraduate Program in Biomedical Engineering, Jeju National University, 102 Jejudaehakno, Jeju-Si, Jeju Special Self-Governing Province 63294 Republic of Korea
| | - Jung Sik Huh
- 1Department of Medicine, School of Medicine, Jeju National University, 102 Jejudaehakno, Jeju-Si, Jeju Special Self-Governing Province 63294 Republic of Korea.,3Department of Urology, Jeju National University Hospital, 15, Aran 13-gil, Jeju-Si, Jeju Special Self-Governing Province 63241 Republic of Korea
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