Researchers are developing a novel biomedical imaging system that combines optical and ultrasound technology to improve diagnosis of life-threatening diseases. Photoacoustic tomography is a noninvasive technique that converts absorbed optical energy into acoustic signal. Pulsed light is sent into body tissue, creating a small increase in temperature that causes tissue to expand and create an acoustic response that can be detected by ultrasound transducer. The ultrasound data is used to visualize the tissue.