Possible temperature increases in soft tissues in the case of nonlinear and linear wave propagation

• Autorzy: Filipczyński L. , Kujawska T. , Tymkiewicz R. , Wójcik J.
• Konferencja: International Symposium on HYDROACOUSTICS AND ULTRASONICS EAA Symposium (formerly 13th FASE Symposium) Gdańsk-Jurata, 12-16 May 1997
• Języki publikacji: EN

Abstrakty

EN

It is well known that the nonlinear propagation increases the absorption of acoustic waves in the medium thus increasing the temperature effects. According to the recently developed new theoretical approach it is possible to determine in a simple way the effective absorption in the case of nonlinear propagation basing on the pulse spectrum analysis [Wójcik, 1996]. In this way it was possible to find the corresponding absorption values occuring in ultrasonography. In this case a classical PVDF membrane hydrophone was used to demonstrate and to measure nonlinear effects. Analysing the obtained wave spectra it was possible to determine the increase of the effective tissue absorption and hence to find the rate of heat generation per unit volume which is crucial for temperature elevations In this way possible temperature increases for the case of nonlinear and linear propagation can be determined.

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 1997
• Tom: Vol. 1
• Strony: 329--332
• Opis fizyczny: Bibliogr. 8 poz., rys.

Twórcy

autor

Filipczyński L.

• lnstitute of Fundamental Technological Research. Polish Academy of Sciences. Department of Ultrasound, Świętokrzyska 21. Warsaw 00-049, Poland

autor

Kujawska T.

• lnstitute of Fundamental Technological Research. Polish Academy of Sciences. Department of Ultrasound, Świętokrzyska 21. Warsaw 00-049, Poland

autor

Tymkiewicz R.

• lnstitute of Fundamental Technological Research. Polish Academy of Sciences. Department of Ultrasound, Świętokrzyska 21. Warsaw 00-049, Poland

autor

Wójcik J.

• lnstitute of Fundamental Technological Research. Polish Academy of Sciences. Department of Ultrasound, Świętokrzyska 21. Warsaw 00-049, Poland

Bibliografia

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