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Photodynamic therapy (PDT) is one of the advanced methods of treatment of skin cancer and surfaces of internal organs.
The basic advantages of PDT are high efficiency and low cost of treatment. PDT technique is needed for providing
fluorescent diagnostics. Laser-based systems are widely applied to the fluorescence excitations for diagnostic because of
a narrow spectrum of fluorescence excitation and high density of radiation. Application of laser systems for carrying out
fluorescent diagnostics gives the image of a tumor distorted by speckles that does not give an opportunity to obtain full
information about the form of a tumor quickly. Besides, these laser excitation systems have complicated structure and
high cost. As a base for the development and creation of a video fluorescent device one of commercially produced
colposcopes was chosen. It allows to decrease cost of the device, and also has enabled to make modernization for already
used colposcopes. A LED-based light source was offered to be used for fluorescence excitation in this work. The
maximum in a spectrum of radiation of LEDs corresponds to the general spectral maximum of protoporphyrin IX (PPIX)
absorption. Irradiance in the center of a light spot is 31 mW/cm2. The receiving optical system of the fluorescent channel
is adjusted at 635 nm where a general spectral maximum of fluorescence PPIX is located. Also the device contains a
RGB video channel, a white light source and a USB spectrometer
LESA-01-BIOSPEC, for measurement of spectra of
fluorescence and diffusion reflections in treatment area. The software is developed for maintenance of the device. Some
studies on laboratory animals were made. As a result, areas with the increased concentration of a PPIX were correctly
detected. At present, the device is used for diagnostics of cancer of female reproductive system in Research Centre for
Obstetrics, Gynecology and Perinatology of the Russian Academy of Medical Sciences (Moscow, Russia).
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