3. Medical Diagnostic Applications of Laser Technology

3.6 Photoacoustic Imaging

Photoacoustic imaging is a hybrid technique that combines laser optics and ultrasound. Short laser pulses are absorbed by tissue chromophores, causing rapid thermal expansion and the generation of acoustic waves. Ultrasound transducers then detect these waves to reconstruct high-contrast images of structures such as blood vessels, tumors, or oxygen saturation patterns.

This method enables deep-tissue imaging with optical contrast and is particularly useful in oncology and vascular imaging, including the early detection of breast cancer, melanoma, and atherosclerotic plaques. Photoacoustic systems are also being developed for handheld diagnostic tools and wearable sensors (Zafar et al., 2021).