Grant: Research Tools and Instruments - Category 1 (<$150,000)

Photoacoustic imaging is an emerging field that utilizes laser pulses to excite ultrasound waves in tissue and uses ultrasound detectors to record the ultrasound waves and reconstruct an image. When tissue absorbs a laser pulse, its local temperature is slightly yet rapidly increased by laser heating. The rapid temperature rising induces acoustic wave through thermal expansion. The advantage of photoacoustic imaging is biochemical specificity and deep penetration. Photoacoustic imaging measures optical absorption which is complementary to the ultrasound measurement of mechanical properties of tissues. Optical absorption has been shown to be able to identify different bio-molecules in tissues. Blood vessels can be imaged because blood has higher absorption than surrounding tissues. Tumors can potentially be detected because they have higher blood flow than normal tissues. A tunable, high-energy, pulsed laser source is requested in this grant. There are a series of research projects that will be based on the new laser system. A photoacoustic imaging system will be developed using the laser as a light source. Signal processing algorithms derived from ultrasound imaging will be applied to the photoacoustic imaging. Nanoparticles will be studied as contrast agent for the photoacoustic imaging. Therefore, this laser will enable investigators at UBC to start a new research direction in the emerging photoacoustic imaging field. The primary application will be in the area of prostate cancer, where photoacoustic imaging will be combined with current ultrasound imaging to enhance the sensitivity and specificity of cancer detection.