• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.205-210
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• 2001

The effectiveness of extracorporeal shock wave lithotripter for the therapy of calculus has been well known in the field of urology. There are many studies about the performance of that and the influence into human body. Among them, it is an impertant issue that cavitation is always deal with shock wave. A medium of the shock wave is related to the cavitation phenomenon. In this paper, therefore, we analysis the spectra of radiated sounds and the break efficiency on focal region due to the medium of shock wave. The results show that the cavitation bubbles produce a harmful on the break efficiency and the stability of the radiated sounds due to the ESWL.

• The Journal of the Acoustical Society of Korea
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• v.19 no.5
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• pp.35-40
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• 2000

In this paper, the relation between the radiated sound and the vibration due to piezoelectric ESWL(Extracorporeal Shock Wave Lithotripter) is examined and the results of the experiments are represented. Next, the relation between the focal point and the vibration of the objects is examined. The same experiments with the objects that can be broken are done and the relation between the vibration and the break efficiency of the phantom is experimentally investigated. These results show that the relativity between the power of the peak frequency and the break efficiency can be confirmed.

• The Journal of the Acoustical Society of Korea
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• v.16 no.6
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• pp.36-40
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• 1997

The effectiveness of Extracorporeal Shock Wave Lithotripter(ESWL) for the therapy of calculus has been generally known in the field of urology. However, there are very little paper investigated about physical characteristics of sounds radiated when phantom is shotting with shock waves. Therefore, this paper, firstly, investigates the sounds radiated when impact is applied to the phantom with a single shot by an impact hammer and a clinical ESWL Next, it determines the variance of the sounds radiated during the breaking process using a piece of chalk as a phantom of a calculus. These results will be applied to the examination of the existence of the calculus at the focus and the monitoring the breaking process.

• Journal of Biomedical Engineering Research
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• v.24 no.5
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• pp.453-458
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• 2003

When the piezoelectric extracorporeal shock wave lithotripter is operated. sounds are generated. In this paper, we present a fact that the sounds are radiated undoubtedly from the object to be hit by the shock waves. For this results. we use the method to identify the sound source location of the radiated sounds by estimating the distance and the bearing from the sound source using one hydrophone. In addition. we investigate the relation between the radiated sounds and the vibrations of the objects using bronze models of disc type with clear vibrating characteristics and present the results of experiments to be analyzed.

• Proceedings of the IEEK Conference
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• 2000.06d
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• pp.186-189
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• 2000

In this paper, the relation between the vibration and the sound radiated due to the piezoelectric ESWL (Extra-corporeal Shock Wave Lithotripter) is examined And the relation between the focus and the vibration of the objects is examined. The same experiments with the objects that can be breton are done and the relation between the vibration and the break efficiency of the phantom is experimentally investigated. These results show that the relativity between the power of the peak frequency and the break efficiency can be confirmed.

• The Journal of the Acoustical Society of Korea
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• v.25 no.1
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• pp.43-48
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• 2006

When the vibration of a phantom induced by Extracorporeal Shock Wave Lithotripter (ESWL) was investigated. we found the fact that the Peak frequency in the Power spectrum shifts from high frequency to low frequency as the number of shots increases[2]. The fact was confirmed experimentally by detecting the peak frequency obtained from the vibrations of bronze models[3]. This Paper investigates the experimental results. For the Purpose. we carried out the computer simulation using the finite element method. It is found that the results from the experiments are computer by computer simulation.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.311-312
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• 1998

It is an important issue that cavitation is always deal with shock wave. During operation with ESWL(Extracorporeal Shock Wave Lithotriptor), the cavitation bubbles are generated at the focal region. This phenomenon is an important problem because the cavitation bubbles have a harmful effect on the disintegration ability and the human body. In this paper, therefore, we investigate the relation between the cavitation and the radiated sound due to the ESWL.

• Proceedings of the Acoustical Society of Korea Conference
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• autumn
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• pp.257-260
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• 1999

본 연구에서는 압전형 쇄석기에 의한 충격파 조사시에 초점위치 및 파쇄정도에 따른 파쇄대상물의 진동과 그 때 들려오는 방사음과의 관계에 대하여 검토해 본 시뮬레이션 결과를 제시한다. 아울러 동일한 실험을 파쇄가능한 대상물에 시행하여 진동과 파쇄효율과의 관계에 대해서도 실험적으로 검토한다. 최종적으로 압전형 쇄석기로 충격파를 대상물에 조사할 때, 충격시의 방사음과 대상물의 진동 및 그것에 따른 파쇄효율의 전체적인 상관성에 대하여 고찰한다.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.287-291
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• 2005

To determine the appropriate session for changing treatment modality according to the size of proximal ureter stone with complete obstruction, We analyzed 201 patients with proximal ureter stone primarily treated by Dornier MPL 9000 lithotripter from January, 2002 to August, 2004. Of total 201 patients, the patients without complete obstruction were 142, and with complete obstruction were 59. In the patients without complete obstruction, the accumulative stone free rate of the first, second, and third session were 68.3%, 86.6%, and 94.4%, respectively. The accumulative stone free rate according to the stone size at third session were 100%, 90.5%, 00.0% in stones less than 10 mm, 10 to less than 20 mm, and larger than or 20 mm, respectively. In the patients with complete obstruction, the accumulative stone free rate of the first, second, and third session were 44.1%, 66.1%, and 76.3%, respectively. The accumulative stone free rate according to the stone size at third session were 100%, 65.5%, 33.3% in stones less than 10 mm, 10 to less than 20 mm, and larger than or 20 mm, respectively. In our study, the size of proximal ureter stone with complete obstruction influenced noticeably on the success rate of extracorporeal shock wave lithotripsy (ESWL). We propose that the proximal ureter stones larger than or 10 mm with complete obstruction are treated by ureteroscopic manipulation than ESWL as the first line treatment modality.