Optoacoustic, or photoacoustic, refers to a phenomenon and related techniques that involve the generation of acoustic waves in a material induced by the absorption of light. The term "optoacoustic" combines "opto-" (related to light) and "acoustic" (related to sound), reflecting the dual nature of this phenomenon.
In optoacoustic imaging, a pulsed laser is typically used to irradiate a sample with short laser pulses. When the laser light is absorbed by the sample, it leads to rapid heating and expansion, resulting in the generation of acoustic waves. These acoustic waves can then be detected using ultrasound transducers, and the collected signals are used to create images of the internal structures of the sample.
Key points about optoacoustic imaging include:
Biomedical imaging: Optoacoustic imaging is commonly used in biomedical applications, providing high-resolution images of tissues and organs. It combines the contrast from optical absorption with the spatial resolution of ultrasound, offering a valuable tool for various medical imaging applications, including cancer detection, functional brain imaging, and monitoring physiological processes.
Multispectral imaging: By using lasers of different wavelengths, optoacoustic imaging can provide information about the distribution of various chromophores in tissues, such as hemoglobin, melanin, and other absorbing compounds. This multispectral approach enhances the specificity of the imaging technique.
Non-invasive imaging: Optoacoustic imaging has the advantage of being non-invasive and capable of imaging deeper tissue layers compared to traditional optical imaging methods. This makes it suitable for studying structures within biological tissues.
Preclinical and clinical applications: While optoacoustic imaging has been widely used in preclinical research, there is ongoing research and development to translate this technology for clinical applications. It holds promise for improving diagnostic capabilities and understanding physiological and pathological processes.