| During the past ten years, much attention has been paid to the studies of sonoluminescence (SL) which was discovered by Frenzel and Schultes in 1934. SL arises from the cavitation process, in which bubbles filled with gas and vapor are generated within the liquid under ultrasonic action. The bubble dynamics, the mechanism of SL, the theory of SL and the potential applications of SL have been reviewed in the thesis.Being noninvasive, nonionizing, and with possible functional contrast for bio-medical diagnosis, optical imaging of tissues has become an active research field in recent years. Several optical imaging techniques being investigated at present include time-resolved optical imaging, frequency-domain optical imaging, optical coherence tomography, opto-acoustic tomography, and ultrasound-modulated optical acousto-optical tomography. All these optical approaches use an external light source, usually a laser. Current imaging technique has the defects of poor penetration ability for the external laser and autofluorescence disturbance from normal tissues. In addition, the image contrast is just based on the difference in optical properties between abnormal and the surrounding normal biological tissues.Because most biological tissues consist of water, ultrasound, as a mechanical wave, has excellent penetration ability and can be focused on any part inside the body, so it is an appropriate excitation source for clinics. In this work, sonoluminescence imaging method and sonodynamic chemiluminescence imaging method was developed. They are with the advantages of both ultrasound and optical imaging technique.Based on the back illuminated cooled CCD, we have designed anexperiment device with high quantum efficiency, high sensitivity and low noise. The lowest detectable light flux of our equipment is 0.09 photons/sec籶ixel. With the equipment, we have done the following work.1. For the first time, we found that tissues under ultrasound exposure could emit photons so called biological sonoluminescence. SL of several types of tissue was measured. The rapid increase of the SL intensity with the acoustic pressure above the thresholds indicated SL signal could be a sensitive measure for tissue imaging. We then carry out experiments on optical confocal tomography by use of SL signal. A high-sensitive confocal scanning setup based on photon counting technique was developed. With the system, we finally obtained images of the objects embedded in both biological tissue and tissue-simulating media. The images showed a high contrast and a lateral resolution of about 100 mm.2. To find out whether SL signal can be detected in vivo, living animals were used. In the experiments, an SL image of a living nude mouse was obtained with a high-sensitive CCD imaging system. Furthermore, to enhance biological sonoluminescence, Fluoresceinyl Cypridina Luminescent Analog (FCLA), a chemiluminescence analysis agent, was used in vivo. With the assistance of FCLA we succeeded in observing an image for a living animal with high contrast and good signal-to-noise ratio.3. Cancer Sonodynamic Therapy (SDT) appears to be a promising modality for cancer treatment, for ultrasound can penetrate deep within the tissue and can be focused in a small region of tumor to chemically activate relatively non-toxic molecules thus minimizing undesirable side effects. The clinic application broadening and improvement of SDT efficiency were hindered because the mechanism of sonodynarm'c action is not clear. To find out the mechanism of sonodynamic action, chemiluminescence method was engaged for the first time to detect theIVactive oxygen spices during sonosensitization. We used chemiluminescent probe to real-timely detect oxygen free radical formation in the sonosensitization of ATX-70 and HpD. The results show that sonosensitization of ATX-70 and HpD in air-saturated solution could largely enhance the CL intensity of FCLA. Nitrogen saturation eliminated the CL. Singlet oxygen were c...
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