Design and application of low-frequency ultrasound and its combination with laser radiation in surgery and therapy

Further development of combined laser-ultrasonic medical technologies is pr esented. An analysis is made of the main effects produced by low-frequency ultrasound on biological tissues. These effects include cavitation, acousti c streamings, acoustic pressure, and mechanical influence. Possible applica tion of low-frequency ultrasound is considered in regard to tumor therapy, bactericidal treatment of infectious tissues, and spray treatment of head a nd neck wounds. Some limitations of ultrasound application in medicine are discussed, and the feasibility of combining laser radiation with ultrasound is studied. A number of new laser-ultrasonic combinations are put forward and developed. They embrace the combination of photodynamic therapy with ul trasonic tumor therapy (sonophotodynamic therapy), laser-ultrasonic wound t reatment (spray treatment), and laser-ultrasonic drug delivery (photophonop horesis). Some of the above-mentioned technologies were tested experimental ly, and the results obtained are considered.