Improvement of SWL Efficacy: Reduction of the Respiration-Induced Kidney Motion by Using an Abdominal Compression Plate.

Background And Purpose: In extracorporeal shockwave lithotripsy (SWL), respiratory-induced motion of the upper urinary tract may hamper stone targeting and disintegration. The objective of this study is to analyze the effect of abdominal compression (AC) to kidney motion and to shock wave efficacy.

Subjects And Methods: The study included 10 volunteers and 10 kidney stone patients.

Monitoring the coupling of the lithotripter therapy head with skin during routine shock wave lithotripsy with a surveillance camera.

Purpose: With lithotripters today the shock waves are typically transmitted into the body via water filled bellows using coupling gel to make contact with the skin. Usually the coupling zone is not visible to the operator. We investigated coupling quality during routine clinical shock wave lithotripsy and the associated effect on shock wave disintegration efficiency.

Ultrasound monitoring of kidney stone extracorporeal shockwave lithotripsy with an external transducer: does fatty tissue cause image distortions that affect stone comminution?

Introduction: Ultrasound imaging, using either an inline or an external transducer, is a standard method for extracorporeal shockwave lithotripsy (SWL) monitoring. This study investigates whether image distortions caused by the low sound speed of fatty tissue could lead to incorrect stone positioning such that disintegration is affected.

Materials And Methods: To define the accuracy needed for SWL monitoring, the dependency of fragmentation efficiency on the distance between stone center and SWL focus was examined by in vitro model stone tests.

Impact of microbubbles on shock wave-mediated DNA uptake in cells in vitro.

Gas-filled microbubbles have been successfully used as gene delivery reagents in combination with diagnostic ultrasound. Although shock wave exposure has been shown to transfect cells with naked DNA in vitro, it has not been tested whether the addition of microbubbles would augment DNA uptake under those conditions. Therefore, the aim of this study was to test the impact of microbubbles on transgene expression in vitro under shock wave exposure conditions.

A new integrated ultrasound system for shockwave lithotripsy.

Background And Purpose: Inline ultrasound monitoring requires good image quality for accurate stone localization, as well as low shockwave shadowing and a robust transducer. In general, conventional transducers designed for another purpose, such as abdominal scanning, are employed. The distance between the transducer and the SWL focus can be varied by a mechanical drive.

Hit/Miss monitoring of ESWL by spectral Doppler ultrasound.

The objective of this study was to investigate spectral Doppler ultrasound (US) for monitoring extracorporeal shock-wave lithotripsy (ESWL). In vitro experiments with model stones showed that Doppler spectra acquired after a shock wave hit result in a high peak followed by a decaying signal. The duration of decay was dependent on shock-wave energy, stone size, gas content of the water and the level of disintegration.

[Quantitative evaluation of cavitation bubble fields induced by lithotripter shock waves].

Extracorporeal shock wave lithotripsy is the world-wide standard therapy for renal stones. The rare-faction phase of the shock wave can induce cavitation within the body. Cavitation contributes to stone disintegration but also to medical side effects.

MR monitoring of focused ultrasound surgery in a breast tissue model in vivo.

The objective of this study was to investigate MRI methods for monitoring focused ultrasound surgery (FUS) of breast tumors. To this end, the mammary glands of sheep were used as tissue model. The tissue was treated in vivo with numerous single sonications which covered extended target volumes by employing a scanning technique.

Multifibre Application in Laser-Induced Interstitial Thermotherapy under On-Line MR Control.

.The application of multiple fibres for the conformal irradiation of tumours by laser-induced interstitial thermotherapy (LITT) has been investigated. A study was performed to evaluate the coagulated zones produced in porcine muscle tissue in vitro.

Quantitative MR temperature monitoring of high-intensity focused ultrasound therapy.

A new quantitative method has been developed for real-time mapping of temperature changes induced by high intensity focused ultrasound (HIFU). It is based on the temperature dependence of the T1 relaxation time and the equilibrium magnetization. To calibrate the temperature measurement, the functional relationship between T1 and temperature was examined in different samples of porcine muscle and fatty tissue.