A new discovery for a biomedical microscopy that can image into tissues to visualize absorbing structures is pioneered by a Systems Design Engineering professor. Dr. Parsin Haji Reza and his colleagues recently reported their work in Optica. By taking advantage of photoacoustic initial pressures, a functional all-optical non-contact optical-resolution photoacoustic microscopy is reported at depths beyond the optical transport mean-free-path of the excitation wavelength. The proposed method is capable of providing optical resolution images to depths of 2.5mm.
PhotoAcoustic Remote Sensing (PARS) allows photoacoustic imaging without the need for any coupling media such as ultrasound gel. This technique uses all-optical detection to remotely detect the photoacoustic signals through air and is capable of providing real-time imaging with cellular resolution. To achieve this, two laser beams at different wavelengths are employed. One is visible light used to generate the signal, while the other is long penetrating near-infrared light used to detect the signal.
The discovery is significant because it will enable new toolsets for biologists and clinicians to remotely image anything that absorbs light in the body including blood, DNA, RNA, lipids, and melanin. Dr. HajiReza's Lab is working on further development of PARS technology for several clinical and pre-clinical applications in the field of oncology, ophthalmology, neurology, dermatology and gastroenterology. [Video]