2024-09-27 09:15:26
Photoacoustic imaging, also known as optoacoustic, is an emerging molecular imaging technique that allows three-dimensional images to be created inside an organism, in a non-invasive and painless way and without using ionizing radiation, through electricity. with flashes of light.
Therefore, using this technique, the attention of specific substances to the body or endogenous chromophores can be selected, such as hemoglobin, melanin, lipids or collagen, among others, by choosing the length or color of the laser where these substances have Greater variation in light absorption with respect to surrounding tissue.
In addition, this imaging technique can benefit from contrast agents or exogenous chromophores to improve images in greater depth. To do this, fluorophores or nanoparticles attached to physical substances, such as proteins or antibodies, are used to obtain more specific images of the areas of the tissue where the concentration is the highest of these materials are available, and functional images, viewing the evolution. of different biological processes.
Researchers from the Institute of Instrumentation for Molecular Imaging (I3M), a joint institution of the Higher Council for Scientific Research (CSIC) and the Polytechnic University of Valencia (UPV), all of these entities in Spain, have obtained the first three-dimensional first. images of melanoma in mice in vivo with a low-cost photoacoustic microscope.
The prototype was written by a group of scientists with the aim of obtaining images of melanomas at depths of several millimeters under the skin and at a high resolution (between 50 and 75 microns). This microscope can help in the early diagnosis of skin cancers like melanoma, a type of skin cancer with the worst prognosis due to its high probability of metastasis, through the bloodstream or lymphatic system.
The prototype was created from a very small microscope design, with a patent granted in early 2024, which allows the use of pulsed laser diodes (PLD) of infrared light (wavelength of 905 nanometers), as a compact source and semiconductor well laser, instead of lasers based on solid-state crystal, bulky and more expensive than PLDs, which are commonly used in such photoacoustic microscopes.
The project has been developed by a team led by Juan José García Garrigós, CSIC researcher at the Ultrasound Laboratory (UMIL) of I3M. This group, led by I3M researcher Alejandro Cebrecos, is a pioneer in Spain in the research and development of photoacoustic imaging. In addition, Professor Francisco Marco Jiménez, from the Institute of Animal Science and Technology (ICTA), of the Polytechnic University of Valencia, has collaborated in the experiments, and the Institute of Biomechanics of Valencia (IBV) has participated in the design of the prototype.
It is worth highlighting the participation of Javier Navarro Calvo, who developed his doctoral thesis on this technology at I3M, and who recently received the Andrés Lara Award for Young Researchers at the Tecniacústica 2024 conference, held in the city of Faro (Portugal).
Experiment in mice
Last July, the I3M group performed several in vivo imaging tests on mice with this photoacoustic microscope, thanks to which, for the first time, images of melanoma in mice were obtained with a low-cost technology based in the pulsed laser diode. According to García Garrigós, “This method allows us to obtain high-resolution tissue images very quickly, that is, in a few minutes for about one square millimeter. All this through its laser scanning design with mirrors. Moreover, the fidelity of the depth image is achieved thanks to the development of new production algorithms, based on the compensation of the response to the spatial impulse, published in the near future in the journals of special education. “
I3M has obtained the first 3D images of melanoma in mice with a low-cost photoacoustic microscope. (Images: I3M / CSIC / UPV)
Currently, the I3M scientist points out, “We are working to develop the design, with a more mobile design aimed at facilitating its clinical operation, in addition to adding another laser light source with a visible wavelength , changing to a two photoacoustic microscope with which, in addition to melanomas, the surrounding vascular networks will be observed with much more sensitivity than in the current design, which, for example, will allow allowed to see the possible angiogenesis associated with tumor progression, thus improving the diagnosis. (Source: Polytechnic University of Valencia)
#Viewing #melanomas #lowcost #photoacoustic #microscope