A CNU research team has developed a photoacoustic fusion imaging method that can observe organs deep in the body without using radiation and without causing pain to the human body.
Professor Lee Chang-ho (Department of Nuclear Medicine) and Professor Kim Hyung-woo (Department of Polymer Convergence Materials Engineering) developed a photoacoustic fusion capable of high-resolution imaging of deep tissue using a nickel-based nanoparticle contrast agent with strong absorption against long-wavelength light (1064 ㎚).
A photoacoustic image is created when human body tissue is instantaneously thermally expanded after light is emitted to the human body and a sound wave (photoacoustic) signal is generated, which is detected by an ultrasonic sensor and imaged.
The joint research team developed the technology by using a long-wavelength laser and developing a contrast agent capable of absorbing it, focusing on the fact that the longer the wavelength of light used, the higher the bio-transmittance and the less cell damage.
This technology has been tested for biocompatibility, and has even demonstrated that the nanoparticles can be injected into the lab rats’ lymph nodes, gastrointestinal tracts, and bladders to obtain photoacoustic images at a depth of up to 3.4 cm.
Existing technologies usually use a short-wavelength laser to observe only soft tissue a few millimeters below the skin, and photoacoustic contrast agents also have a limitation in that they cannot transmit short-wavelength light (650-900 nm) deep into the human body.
The research team stated, "This technology can observe and visualize organs and diseases deep inside the body non-invasively while avoiding the risk of exposure, unlike CT, which requires radioactive materials. It is expected that the clinical application will be possible sooner because the 1,064 ㎚ laser device is relatively inexpensive and can be used with general commercial ultrasonic equipment."
