PHOTODYNAMIC UNIT PROVIDING VISUAL
MONITORING OF THE FLUORESCENT INDICATING
OF IRRADIATED AREA
Designed and manufactured by CONSTYLES, (Moscow),
with the participation of RADA-PHARMA™ Ltd (Moscow)
ElAN photodynamic unit is based on a dedicated video camera equipped with a charge-coupled device (camera) and laser semiconductor diodes of 650 – 670 Nm wavelength; the device is designed for the visual diagnosis and photodynamic treatment of pathologic dysplasia and cancer cell colonies. The device can be used as a separate unit or combined with therapeutic laser apparatus, surgical lasers, laser spectrometers, and other diagnostic units included in the equipment of photodynamics rooms in clinics, hospitals, and research medical centers.
The key components of the unit are represented by a matrix of semiconductor diodes and dedicated video camera with a special light filter providing exact recording of fluorescence process. The matrix includes a series of light-emitting diodes built-in with a tight pack enabling focusing (within specified limits) of integrated radiation of the diodes. The unit allows the use of standard video-image reproduction equipment. The matrix provides radiation beaming of a pathologic zone that has been previously sensibilized by a photosensitizer. In this process, the diode (matrix) emission wavelength shall match the absorption band of a photosensitizer preparation. The radiation is used to cause the necrosis; this process is accompanied by the fluorescence effect provided by the photosensitizer accumulated in the radiation area.
The video monitoring of the radiation area enables recording of the fluorescence zone as the visually explicit bright zone compensating the radiation background of the matrix. The said monitoring of the fluorescence zone with accumulated photosensitizer is a diagnostic imaging procedure. This diagnostic imaging can precede or accompany the radiation therapy, or can be performed as a separate diagnostic procedure. The matrix irradiation intensity (energy density) can be lowered in respect to the therapeutic implication.
A video image recorded by display can be stored in analog or digital form. The latter makes it possible to provide computer processing of the fluorescence zone image for the purpose of obtaining the additional quantitative information: a fluorescence intensity distribution over the surface, a relative quantity of the fluorescence. These tasks will be implemented in the further designs.
The unit enables the use of various types of photosensitizers, in the first instance, high-performance and low-toxic preparations, such as, Radachlorin photosensitizer. The unit with Radachlorin has successfully passed test to satisfaction.
|Average laser power density in the focal zone, mW\cm2:||60|
|Wavelength of radiation, Nm||650-670|
|Wavelength of fluorescence, Nm||670-680|
|Matrix size, mm||300×300|
|Focal area, ám2||40|
|Target laser wavelength, Nm||532|
|Luminiferous fiber core diameter, (microns)||300(500)…600|
|Power supply||220V, 50Hz, 250W|
|Maximum weight, kg|
|Operational life, hours,||>1500|
According to the Resolution of the Committee for New Medical Equipment of the Ministry of Health of the Russian Federation, Protocol No. 2 of 04.03.2004 , the unit is recommended for large-scale manufacturing and use in the medical practice.