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Information × Registration Number 0205U000165, 0102U002345 , R & D reports Title Development of new methods optical diagnostic of human organism on the basis NIR-spectroscopy. popup.stage_title Head Plaksij Yurij Stepanovich, Registration Date 18-01-2005 Organization Institute of the Applied Problems of Physics and Biophysics of the National Academy of Scienes popup.description2 The subject of examination is human biotissue іn vіvo. The goal of the work is to elaborate new diagnostic procedures on the basis of red and short-range infrared spectroscopy taking into account the features of biological tissue functioning. Research techniques are infrared spectroscopy and pulsoximetry. There are studied the processes of light propagation in alive biological tissues, which model is accepted the three-dimensional bounded space. A three-layer model is used comprising bloodless top and bottom layers, and intermediate one consisting of two components (blood and tissue) and being randomly heterogeneous. At that it is considered the scattering of photons in the matter dominates over absorption. The theoretical consideration and mathematical modeling of light propagation in tissue under conditions of existence of a pulse wave were carried out. The distributions of modulation index of light passed through a biotissue and backscattered depending on a distance between the observation point andthe beam axis are obtained. A method is developed for determination of concentration of hemoglobin derivatives present in small quantities (methemoglobin, carboxihemoglobin). The changes of oxyhemoglobin concentration under the action of physiological and physical factors are studied. The developed method of optoelectronic determination of cardiovascular system performances enables one from the analysis of amplitude-temporal characteristics of photoplethysmographic curve to determine such diagnostic parameters as duration of anacrotic and dicrotic phases, duration of fast and slow blood filling, period of expulsion, dicrotic and diastolic indices, temporal and peak indices of vascular tone. In contrast to rheographic method the use of photoplethysmogram gives a possibility to conduct local examinations, to determine the changes in status of vessels along their bed, and eliminates an electrical contact and electrical action on a patient carrying out examinations.5635 Product Description popup.authors popup.nrat_date 2020-04-02 Close