doi: 10.17586/2226-1494-2018-18-6-939-945


A. V. Belikov, S. V. Gagarsky, A. N. Sergeev, S. N. Smirnov, A. M. Zagorulko

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For citation: Belikov A.V., Gagarsky S.V., Sergeev A.N., Smirnov S.N., Zagorulko A.M. Study of acoustic signal during laser hydroacoustic processing of biological tissue by microsecond pulses of ytterbium-erbium glass laser radiation. Scientific and Technical Journal of Information Technologies, Mechanics and Optics , 2018, vol. 18, no. 6, pp. 939–945 (in Russian). doi: 10.17586/2226-1494-2018-18-6-939-945

Subject of Research.The paper describes the research results of an acoustic signal recorded by a hydrophone while effect on a liquid by microsecond pulses of laser radiation with a wavelength of 1.54 μm and different time substructure. We discuss the influence of energy and time substructure of the laser pulse on the magnitude of generated pressure drops in the liquid and removal efficiency of cataract eye lens tissues. Method. Microsecond pulses of ytterbium-erbium glass laser radiation with different peak power of the "leading" spike and equivalent energy were delivered to the volume of distilled water through an optical fiber. The acoustic signal was registered with "NP 10-1" needle hydrophone (Dapco Inc., USA). An in vitro hydroacoustic treatment of cataract human eye lens was performed. Main Results. We obtained the dependences of the amplitude of the first (thermo-optical) and the second (associated with "collapse-rebound" process of a steam-gas cavity) components of the acoustic signal on the pulse energy for laser pulses with different time substructures. It was established that with an increase in the peak power of the "leading" spike of microsecond pulse, the threshold for the appearance of the second component decreases, and the maximum amplitude of both components increases. The angular distributions of the amplitude of acoustic signal components were obtained. It was found that the first component has a pronounced maximum amplitude in a direction perpendicular to the optical axis of the fiber, whereas the angular distribution of the second component is more uniform. In the in vitro experiment, it was shown that an increase in the peak power of the "leading" spike results in a significant increase in the removed volume and removal efficiency of the human cataract eye lens. Practical Relevance. The obtained results can be used to optimize the parameters of laser radiation for processing of tissue surrounded by a liquid, for example, during laser cataract extraction.

Keywords: laser hydroacoustic processing, ytterbium-erbium glass laser, microsecond pulses, leading spike, acoustic signal, hydrophone, steam-gas cavity, biological tissues

Acknowledgements. This work was financially supported by the Government of the Russian Federation (Grant 08-08).

1. Fedorov S.N., Kopaeva V.G., Andreev Yu.V., Bogdalova E.G., Belikov A.V. Laser technology of cataract extraction. Oftalmokhirurgiya, 1999, no. 1, pp. 3–12. (in Russian)
2. Kopaeva V.G., Andreev Yu.V. Laser Extraction of a Cata-ract. Moscow, Oftalmologiya Publ., 2011, 262 p. (in Rus-sian)
3. Belikov A.V., Gagarsky S.V., Gubin A.B., Weiner S.Ya., Sergeev A.N., Smirnov S.N. Subjoule diode-pumped ytter-biumerbium glass laser with cavity dumping for cataract extraction. Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2015, vol. 15, no. 6, pp. 1021–1029. doi: 10.17586/2226-1494-2015-15-6-1021-1029
4. Hale G.M., Querry M.R. Optical constants of water in the 
200-nm to 200-μm wavelength region. Applied Optics, 1973, vol. 12, no. 3, pp. 555–563. doi: 10.1364/AO.12.000555
5. Belikov A.V., Gagarsky S.V., Sergeev A.N., Smirnov S.N. Study of hydrodynamic processes in liquids under the in-fluence of powerful microsecond Yb,Er:Glass laser pulses. Journal of Instrument Engineering, 2017, vol. 60, no. 4, pp. 367–374. 
doi: 10.17586/0021-3454-2017-60-4-367-374
6. Jansen E.D., Asshauer T., Frenz M., Motamedi M., Dela-cretaz G., Welch A.J. Effect of pulse duration on bubble formation and laser-induced pressure waves during holmi-um laser ablation. Lasers in Surgery and Medicine, 1996, vol. 18, no. 3, pp. 278–293. doi: 10.1002/(SICI)1096-9101(1996)18:3<278::AID-LSM10>3.0.CO;2-2
7. Frenz M., Pratisto H., Konz F., Jansen E.D., Welch A.J., Weber H.P. Comparison of the effects of absorption coef-ficient and pulse duration of 2.12-µm and 2.79-µm radia-tion on laser ablation of tissue. IEEE Journal of Quantum Electronics, 1996, vol. 32, no. 12, pp. 2025–2036. doi: 10.1109/3.544746
8. Bufetova G.A., Nikolaev D.A., Seregin V.F., Shcherbakov I.A., Tsvetkov V.B. Long pulse lasing with Q-switching by FTIR shutter. Laser Physics, 1999, vol. 9, no. 1, pp. 314–318.
9. Denker B.I., Osiko V.V., Sverchkov S.E. et al. Highly efficient erbium glass lasers with Qswitching based on frustrated total 
internal reflection. Soviet Journal of Quantum Electronics, 1992, vol. 22, no. 6, pp. 500–503. (in Russian)
10. Buratto L., Apple D.J., Zanini M. Phacoemulsification: Principles and Techniques. 2nd ed. SLACK Incorporated, 2003, 754 p.
11. Belikov A.V., Gagarsky S.V., Zagorul'ko A.M., Sergeev A.N., Smirnov S.N. Formation of the vapor-gas cavity in the laser hydroacoustic treatment of biotissue in a liquid by microsecond laser pulses. Journal of Instrument Engi-neering, 2018. (in press)
12. Frenz M., Paltauf G., Schmidt-Kloiber H. Laser-generated 
cavitation in absorbing liquid induced by acoustic diffrac-tion. 
Physical Review Letters, 1996, vol. 76, no. 19, pp. 3546–3549. 
doi: 10.1103/PhysRevLett.76.3546
13. Paltauf G., Schmidt-Kloiber H., Frenz M. Photoacoustic waves excited in liquids by fiber-transmitted laser pulses. Journal of the Acoustical Society of America, 1998, vol. 104, no. 2, pp. 890–897. doi: 10.1121/1.423334
14. Lu T., Li Z.J. Underwater holmium-laser-pulse-induced 
complete cavitation bubble movements and acoustic tran-sients. 
Chinese Science Bulletin, 2011, vol. 56, no. 12, pp. 1226–1229. doi: 10.1007/s11434-011-4367-5
15. Lauterborn W., Kurz T., Geisler R., Schanz D., Lindau O. Acoustic cavitation, bubble dynamics and sonolumines-cence. Ultrasonics Sonochemistry, 2007, vol. 14, no. 4, pp. 484–491. doi: 10.1016/j.ultsonch.2006.09.017
16. Duck F.A. Physical Properties of Tissues: A Comprehensive Reference Book. London, Academic Press, 2013, 346 p.

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