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Chen J, Mishra A, Medairos R, Antonelli J, Preminger GM, Lipkin ME, Zhong P. In vitro investigation of stone ablation efficiency, char formation, spark generation, and damage mechanism produced by thulium fiber laser. Urolithiasis 2023; 51:124. [PMID: 37917225 PMCID: PMC10880548 DOI: 10.1007/s00240-023-01501-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 10/25/2023] [Indexed: 11/04/2023]
Abstract
To investigate stone ablation characteristics of thulium fiber laser (TFL), BegoStone phantoms were spot-treated in water at various fiber tip-to-stone standoff distances (SDs, 0.5 ~ 2 mm) over a broad range of pulse energy (Ep, 0.2 ~ 2 J), frequency (F, 5 ~ 150 Hz), and power (P, 10 ~ 30 W) settings. In general, the ablation speed (mm3/s) in BegoStone decreased with SD and increased with Ep, reaching a peak around 0.8 ~ 1.0 J. Additional experiments with calcium phosphate (CaP), uric acid (UA), and calcium oxalate monohydrate (COM) stones were conducted under two distinctly different settings: 0.2 J/100 Hz and 0.8 J/12 Hz. The concomitant bubble dynamics, spark generation and pressure transients were analyzed. Higher ablation speeds were consistently produced at 0.8 J/12 Hz than at 0.2 J/100 Hz, with CaP stones most difficult yet COM and UA stones easier to ablate. Charring was mostly observed in CaP stones at 0.2 J/100 Hz, accompanied by strong spark-generation, explosive combustion, and diminished pressure transients, but not at 0.8 J/12 Hz. By treating stones in parallel fiber orientation and leveraging the proximity effect of a ureteroscope, the contribution of bubble collapse to stone ablation was found to be substantial (16% ~ 59%) at 0.8 J/12 Hz, but not at 0.2 J/100 Hz. Overall, TFL ablation efficiency is significantly better at high Ep/low F setting, attributable to increased cavitation damage with less char formation.
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Affiliation(s)
- Junqin Chen
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Box 90300, Durham, NC, 27708, USA
| | - Arpit Mishra
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Box 90300, Durham, NC, 27708, USA
| | - Robert Medairos
- Department of Urology, Duke University Medical Center, Durham, NC, USA
| | - Jodi Antonelli
- Department of Urology, Duke University Medical Center, Durham, NC, USA
| | - Glenn M Preminger
- Department of Urology, Duke University Medical Center, Durham, NC, USA
| | - Michael E Lipkin
- Department of Urology, Duke University Medical Center, Durham, NC, USA
| | - Pei Zhong
- Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Box 90300, Durham, NC, 27708, USA.
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Nolasco P, Dos Anjos AJ, Dias J, Coelho PV, Coelho C, Evaristo M, Cavaleiro A, Maurício A, Pereira MFC, Infante V, Alves de Matos AP, Martins RC, Carvalho PA. Local Response of Sialoliths to Lithotripsy: Cues on Fragmentation Outcome. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2017; 23:584-598. [PMID: 28434428 DOI: 10.1017/s143192761700037x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Lithotripsy methods show relatively low efficiency in the fragmentation of sialoliths compared with the success rates achieved in the destruction of renal calculi. However, the information available on the mechanical behavior of sialoliths is limited and their apparently tougher response is not fully understood. This work evaluates the hardness and Young's modulus of sialoliths at different scales and analyzes specific damage patterns induced in these calcified structures by ultrasonic vibrations, pneumoballistic impacts, shock waves, and laser ablation. A clear correlation between local mechanical properties and ultrastructure/chemistry has been established: sialoliths are composite materials consisting of hard and soft components of mineralized and organic nature, respectively. Ultrasonic and pneumoballistic reverberations damage preferentially highly mineralized regions, leaving relatively unaffected the surrounding organic matter. In contrast, shock waves leach the organic component and lead to erosion of the overall structure. Laser ablation destroys homogeneously the irradiated zones regardless of the mineralized/organic nature of the underlying ultrastructure; however, damage is less extensive than with mechanical methods. Overall, the present results show that composition and internal structure are key features behind sialoliths' comminution behavior and that the organic matter contributes to reduce the therapeutic efficiency of lithotripsy methods.
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Affiliation(s)
- Pedro Nolasco
- 1CeFEMA,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
| | - Ana J Dos Anjos
- 2Clindem-Clínica dentária e médica Lda.,Rua José Morais,23 r/c Dto,2685-076 Sacavém,Loures,Portugal
| | - José Dias
- 3Service of Stomotology,Centro Hospitalar de Lisboa Norte,Av. Prof. Egas Moniz,1649-035 Lisboa,Portugal
| | - Paulo V Coelho
- 4Nova Medical School - Medical Sciences Faculty (NMS/FCM),Nova University of Lisbon,Campo Mártires da Pátria,130,1169-056 Lisboa,Portugal
| | - Carla Coelho
- 4Nova Medical School - Medical Sciences Faculty (NMS/FCM),Nova University of Lisbon,Campo Mártires da Pátria,130,1169-056 Lisboa,Portugal
| | - Manuel Evaristo
- 6EG-CEMUC,Department of Mechanical Engineering,University of Coimbra,R. Luís Reis Santos,P-3030 788 Coimbra,Portugal
| | - Albano Cavaleiro
- 6EG-CEMUC,Department of Mechanical Engineering,University of Coimbra,R. Luís Reis Santos,P-3030 788 Coimbra,Portugal
| | - António Maurício
- 7CERENA,Department of Civil Engineering, Architecture and Georesources,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
| | - Manuel F C Pereira
- 7CERENA,Department of Civil Engineering, Architecture and Georesources,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
| | - Virgínia Infante
- 8LAETA,IDMEC,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
| | | | - Raúl C Martins
- 10IT,Department of Bioengineering,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
| | - Patricia A Carvalho
- 1CeFEMA,Instituto Superior Técnico,University of Lisbon,Av. Rovisco Pais,1049-001 Lisboa,Portugal
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Ikeda T, Yoshizawa S, Koizumi N, Mitsuishi M, Matsumoto Y. Focused Ultrasound and Lithotripsy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:113-29. [PMID: 26486335 DOI: 10.1007/978-3-319-22536-4_7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Shock wave lithotripsy has generally been a first choice for kidney stone removal. The shock wave lithotripter uses an order of microsecond pulse durations and up to a 100 MPa pressure spike triggered at approximately 0.5-2 Hz to fragment kidney stones through mechanical mechanisms. One important mechanism is cavitation. We proposed an alternative type of lithotripsy method that maximizes cavitation activity to disintegrate kidney stones using high-intensity focused ultrasound (HIFU). Here we outline the method according to the previously published literature (Matsumoto et al., Dynamics of bubble cloud in focused ultrasound. Proceedings of the second international symposium on therapeutic ultrasound, pp 290-299, 2002; Ikeda et al., Ultrasound Med Biol 32:1383-1397, 2006; Yoshizawa et al., Med Biol Eng Comput 47:851-860, 2009; Koizumi et al., A control framework for the non-invasive ultrasound the ragnostic system. Proceedings of 2009 IEEE/RSJ International Conference on Intelligent Robotics and Systems (IROS), pp 4511-4516, 2009; Koizumi et al., IEEE Trans Robot 25:522-538, 2009). Cavitation activity is highly unpredictable; thus, a precise control system is needed. The proposed method comprises three steps of control in kidney stone treatment. The first step is control of localized high pressure fluctuation on the stone. The second step is monitoring of cavitation activity and giving feedback on the optimized ultrasound conditions. The third step is stone tracking and precise ultrasound focusing on the stone. For the high pressure control we designed a two-frequency wave (cavitation control (C-C) waveform); a high frequency ultrasound pulse (1-4 MHz) to create a cavitation cloud, and a low frequency trailing pulse (0.5 MHz) following the high frequency pulse to force the cloud into collapse. High speed photography showed cavitation collapse on a kidney stone and shock wave emission from the cloud. We also conducted in-vitro erosion tests of model and natural kidney stones. For the model stones, the erosion rate of the C-C waveform showed a distinct advantage with the combined high and low frequency waves over either wave alone. For optimization of the high frequency ultrasound intensity, we investigated the relationship between subharmonic emission from cavitation bubbles and stone erosion volume. For stone tracking we have also developed a non-invasive ultrasound theragnostic system (NIUTS) that compensates for kidney motion. Natural stones were eroded and most of the resulting fragments were less than 1 mm in diameter. The small fragments were small enough to pass through the urethra. The results demonstrate that, with the precise control of cavitation activity, focused ultrasound has the potential to be used to develop a less invasive and more controllable lithotripsy system.
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Affiliation(s)
| | - Shin Yoshizawa
- Department of Communications Engineering, Tohoku University, Sendai, Miyagi, Japan
| | - Norihiro Koizumi
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, Japan
| | - Mamoru Mitsuishi
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, Japan
| | - Yoichiro Matsumoto
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, Japan.
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Nyame YA, De S, Sarkissian C, Brown R, Kartha G, Babbar P, Monga M. Kidney Stone Models for In Vitro Lithotripsy Research: A Comprehensive Review. J Endourol 2015; 29:1106-9. [DOI: 10.1089/end.2014.0850] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yaw A. Nyame
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Shubha De
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Carl Sarkissian
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Robert Brown
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Ganesh Kartha
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Paurush Babbar
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Manoj Monga
- Department of Urology, Glickman Urologic and Kidney Institute, Cleveland Clinic Foundation, Cleveland, Ohio
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Lee HP, Leong D, Heng CT. Characterization of kidney stones using thermogravimetric analysis with electron dispersive spectroscopy. ACTA ACUST UNITED AC 2011; 40:197-204. [DOI: 10.1007/s00240-011-0428-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Accepted: 09/21/2011] [Indexed: 11/28/2022]
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Venkatesan N, Shroff S, Jeyachandran K, Doble M. Effect of uropathogens on in vitro encrustation of polyurethane double J ureteral stents. ACTA ACUST UNITED AC 2010; 39:29-37. [DOI: 10.1007/s00240-010-0280-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2009] [Accepted: 05/15/2010] [Indexed: 12/01/2022]
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Ikeda T, Yoshizawa S, Tosaki M, Allen JS, Takagi S, Ohta N, Kitamura T, Matsumoto Y. Cloud cavitation control for lithotripsy using high intensity focused ultrasound. ULTRASOUND IN MEDICINE & BIOLOGY 2006; 32:1383-97. [PMID: 16965979 DOI: 10.1016/j.ultrasmedbio.2006.05.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2005] [Revised: 04/24/2006] [Accepted: 05/11/2006] [Indexed: 05/11/2023]
Abstract
Cloud cavitation is potentially the most destructive form of cavitation. When the cloud cavitation is acoustically forced into a collapse, it has the potential to concentrate a very high pressure, more than 100 times the acoustic pressure, at its center. We experimentally investigate a method to control the collapse of high intensity focused ultrasound (HIFU)-induced cloud cavitation to fragment kidney stones. Our study examines a novel two-frequency wave designed to control the cloud cavitation (cavitation control [C-C] waveform); a high-frequency ultrasound pulse (1 to 4 MHz) to create the cloud cavitation and a low-frequency trailing pulse (545 kHz) following the high-frequency pulse to force the cloud into collapse. High-speed photography has revealed that a localized distribution of the cloud cavitation can be produced within 1 mm on the solid surface by the high-frequency pulse. The low-frequency ultrasound was irradiated to the high-frequency-induced cloud cavitation. A subsequent shock wave emitted from the cloud cavitation was observed both in the shadowgraph photography and the remote hydrophone measurement. Furthermore, in vitro erosion tests of model and natural stones were conducted. In the case of model stones, the erosion rate of the C-C waveform showed a distinct advantage with the combined high- and low-frequency waves over either wave alone. Natural stones were eroded and most of the resulting fragments were less than 1 mm in diameter. The results show that the control of the cloud cavitation has untapped potential for the lithotripsy applications upon further optimization of the ultrasound parameters and complementary in vivo studies.
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Affiliation(s)
- Teiichiro Ikeda
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, Japan.
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Nondestructive analysis of urinary calculi using micro computed tomography. BMC Urol 2004; 4:15. [PMID: 15596006 PMCID: PMC544194 DOI: 10.1186/1471-2490-4-15] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Accepted: 12/13/2004] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Micro computed tomography (micro CT) has been shown to provide exceptionally high quality imaging of the fine structural detail within urinary calculi. We tested the idea that micro CT might also be used to identify the mineral composition of urinary stones non-destructively. METHODS Micro CT x-ray attenuation values were measured for mineral that was positively identified by infrared microspectroscopy (FT-IR). To do this, human urinary stones were sectioned with a diamond wire saw. The cut surface was explored by FT-IR and regions of pure mineral were evaluated by micro CT to correlate x-ray attenuation values with mineral content. Additionally, intact stones were imaged with micro CT to visualize internal morphology and map the distribution of specific mineral components in 3-D. RESULTS Micro CT images taken just beneath the cut surface of urinary stones showed excellent resolution of structural detail that could be correlated with structure visible in the optical image mode of FT-IR. Regions of pure mineral were not difficult to find by FT-IR for most stones and such regions could be localized on micro CT images of the cut surface. This was not true, however, for two brushite stones tested; in these, brushite was closely intermixed with calcium oxalate. Micro CT x-ray attenuation values were collected for six minerals that could be found in regions that appeared to be pure, including uric acid (3515 - 4995 micro CT attenuation units, AU), struvite (7242 - 7969 AU), cystine (8619 - 9921 AU), calcium oxalate dihydrate (13815 - 15797 AU), calcium oxalate monohydrate (16297 - 18449 AU), and hydroxyapatite (21144 - 23121 AU). These AU values did not overlap. Analysis of intact stones showed excellent resolution of structural detail and could discriminate multiple mineral types within heterogeneous stones. CONCLUSIONS Micro CT gives excellent structural detail of urinary stones, and these results demonstrate the feasibility of identifying and localizing most of the common mineral types found in urinary calculi using laboratory CT.
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Abstract
To improve the efficacy of extracorporeal shock wave lithotripsy (ESWL) treatment, it is desirable to identify the physical properties of urinary calculi could offer direct correlation with their fragilities during ESWL and thus could be used to guide treatment procedures for more effective stone fragmentation. Thirty stone specimens removed surgically were compressed by an axial testing system to measure the compressive strength and trace the stress-strain curve. Image analysis software SigmaScan (Jandel Co.) was used to calculate the area under the stress-strain curve, the modulus of toughness, for each stone. The values of compressive strength measured were similar to those reported by other researchers. The modulus of toughness of urinary calculi correlates with clinical representation of the stone fragility during ESWL. The modulus of toughness could be an index to evaluate the physical property of urinary calculi that could be used to guide treatment procedures for more effective stone fragmentation.
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Affiliation(s)
- Shyh-Jen Wang
- Department of Surgery, Veterans General Hospital-Taipei, and National Yang-Ming University, Taiwan, ROC.
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11
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12
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Zhong P, Preminger GM. Mechanisms of differing stone fragility in extracorporeal shockwave lithotripsy. J Endourol 1994; 8:263-8. [PMID: 7981735 DOI: 10.1089/end.1994.8.263] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Clinical experience with extracorporeal shockwave lithotripsy (SWL) has demonstrated significant variations in stone fragility. To understand the physical mechanisms of the differences, we quantitatively determined shockwave-stone interaction under clinically relevant SWL conditions for six stone compositions: calcium oxalate monohydrate (COM), struvite (MAPH), calcium apatite (CA), uric acid (UA), brushite, and cystine. We also characterized the acoustic and mechanical properties of the stones using ultrasound and microindentation techniques. Our results show that renal calculi have distinctly different acoustic and mechanical properties. Higher wave speed, Young's modulus, and fracture toughness were measured from COM and cystine stones, whereas lower values of the corresponding properties were found in CA and MAPH, and the values for brushite and UA stones were in between. Computer modeling of shockwave propagation revealed that under the same shockwave intensity, larger deformation was induced in CA and MAPH stones than in COM and cystine stones. In addition, multiple reflected tensile waves were predicted for stones with concentric layer structure, indicating their susceptibility to shockwave fragmentation. These findings elucidate the mechanisms of the differences in stone fragility observed clinically. Their implications to SWL are discussed.
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Affiliation(s)
- P Zhong
- Department of Surgery, University of Texas Southwestern Medical Center, Dallas
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Chuong CJ, Zhong P, Preminger GM. Acoustic and mechanical properties of renal calculi: implications in shock wave lithotripsy. J Endourol 1993; 7:437-44. [PMID: 8124332 DOI: 10.1089/end.1993.7.437] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The acoustic and mechanical properties of renal calculi dictate how a stone interacts with the mechanical forces produced by shock wave lithotripsy; thus, these properties are directly related to the success of the treatment. Using an ultrasound pulse transmission technique, we measured both longitudinal and transverse (or shear) wave propagation speeds in nine groups of renal calculi with different chemical compositions. We also measured stone density using a pycnometer based on Archimedes' principle. From these measurements, we calculated wave impedance and dynamic mechanical properties of the renal stones. Calcium oxalate monohydrate and cystine stones had higher longitudinal and transverse wave speeds, wave impedances, and dynamic moduli (bulk modulus, Young's modulus, and shear modulus), suggesting that these stones are more difficult to fragment. Phosphate stones (carbonate apatite and magnesium ammonium phosphate hydrogen) were found to have lower values of these properties, suggesting they are more amenable to shock wave fragmentation. These data provide a physical explanation for the significant differences in stone fragility observed clinically.
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Affiliation(s)
- C J Chuong
- Joint Biomedical Engineering Program, University of Texas, Arlington
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Characterization of fracture toughness of renal calculi using a microindentation technique. ACTA ACUST UNITED AC 1993. [DOI: 10.1007/bf00591608] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Chuong CJ, Zhong P, Preminger GM. A comparison of stone damage caused by different modes of shock wave generation. J Urol 1992; 148:200-5. [PMID: 1613869 DOI: 10.1016/s0022-5347(17)36553-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A standard stone phantom was used to compare stone damage after extracorporeal shock wave administration from electrohydraulic, electromagnetic and piezoelectric lithotripters. For each machine, a low and high shock wave intensity setting was chosen: 18 & 24 kV for electrohydraulic; 16 & 19 kV for electromagnetic; power levels 1 and 4 for piezoelectric. The shock wave was focused either at the front (surface facing the wave source) or back surface of the stone and 50, 100, 200 or 400 shocks were delivered to different stone groups. Effects of varying physical properties in the stone phantom were also investigated. Stone damage was described in terms of volume loss and both depth and width of the resulting damage crater. At the lower intensity settings, all three machines produced stone volume loss which was linearly related to the number of shock delivered. At higher intensity settings, volume loss increased rapidly as the number of shocks increased. With the same number of shocks, stone volume loss was greatest with the electrohydraulic machine, followed by electromagnetic and piezoelectric lithotripters for both low and high intensity settings. Damage craters from the piezoelectric device were narrow and deep; those from the electromagnetic machine were of the shape of a right angle circular cone; whereas those from the electrohydraulic lithotripter were shallow and wide. At the high intensity settings, damage from the piezoelectric and electrohydraulic lithotripters appeared to depend upon the position of the focal point with a higher volume loss when the shock waves were targeted at the front surface of the stone. For the electromagnetic device, a higher volume loss was found when we positioned the focal point at the back surface of the stone phantom. Stone phantoms with lower mechanical strength and acoustic impedance were more easily damaged than those with higher values. Finally, a computer regression model was developed to express volume loss in terms of the intensity setting, focal position and number of shocks for each lithotripter.
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Affiliation(s)
- C J Chuong
- Joint Biomedical Engineering Program, University of Texas, Arlington 76019
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