A system for assessing the functional state of blood flow in the skin surface layers by the speckle structure of multiply scattered optical radiation

Assessment of the parameters of skin microcirculation is an urgent and important task of modern medicine in the development of methods for diagnosing diseases of the nervous system. The system for assessing the functional state of blood flow in the skin surface layers in the wavelength range from 400 to 850 nm has been improved based on the use of an extended mathematical model of the propagation of optical radiation in human skin by taking into account additional parameters: optical anisotropy of the skin, diameter and shape of erythrocytes in the dermis layer, blood pressure in the brachial artery in the range from 90/60 to 195/130 mm·Hg, plasma protein concentration in the blood (α1, α2, β1, β2, γ-globulins and fibrinogen, g/l), rheological properties of blood flow with a diameter of blood vessels from 4.5 to 500 microns in the skin surface layers, skin temperature from +35 to +41 °C. The developed system makes it possible to determine the severity of microhemodynamic shifts in relation to metabolic disorders, improve diagnosis and evaluate the treatment efficacy of a number of neurological disorders; it also made it possible to reduce the patient examination time and increase the accuracy of measuring the blood flow microcirculation parameters by 10 % (linear and volumetric blood flow velocities) to detect blood flow disturbances in the surface layers of the skin in the normal and abnormal condition of the nervous system.

system, skin, biophysical and structural parameters, blood, contrast, coherent radiation, speckle structure

1. Abramovich N.D., Dik S.К. [Zavisimost razmerov speckl-pyaten i ih contrasta ot biophizicheskih i strukturnyh parametrov biontani]. Pribory i metody izmerenii. 2017;8(2):177-187. DOI: 10.21122/2220- 9506-2017-8-2-177-187. (In Russ.)

2. Abramovich N.D., Dick S.K., Sontea V.P. Speckle pattern of radiation scattered of soft biological tissues. Light fields outside tissue. Journal of technical university of Moldova and moldavian engineering association. 2016;(4):32-36.

3. Dik S.K. [Lazerno-opticheskiye metody i tekhnicheskiye sredstva kontrolya funktsional'nogo sostoyaniya bioob"yektov]. Minsk: BSUIR; 2014. (In Russ.)

4. Barun V.V., Dik S.K., Ivanov A.P., Abramovich N.D. [Modelirovaniye struktury svetovogo spekl-polya vnutri mnogosloynoy tkani kozhi cheloveka]. Inzhenerno-fizicheskiy zhurnal. 2013;86(6):1288-1295. DOI: 10.1007/s10891-013-0962-4. (In Russ.)

5. Zege E.P., Katsev I.L., Ivanov A.P. [Perenos izobrazheniya v rasseivayushchey srede]. Minsk: Nauka i tekhnika; 1985. (In Russ.) 6. Van de Khyulst G. [Rasseyaniye sveta malymi chastitsami]. Moskva: Izd-vo inostr. literatury; 1961. (In Russ.)

6. Ivanov A.P., Katsev I.L. [O spekl-strukture svetovogo polya v dispersnoy srede, osveshchennoy lazernym puchkom.]. Kvantovaya Elektronika. 2005;35(7):670-674. (In Russ.)

7. Tuchin V.V. [Optika biologicheskikh tkaney: metody rasseyaniya sveta v meditsinskoy diagnostike]. Moskow: Fizmatlit; 2013. (In Russ.)

8. Abramovich N.D., Dik S.К. Vsilevskaya L.А., Khludeyev I.I. [Ocenka fynctionalnogo sostoyaniya kozhnoi microhemodinamiki metodami dopplerovskoi floymetrii i speckl-metrii]. Doklady BGUIR = Doklady BGUIR. 2019;121(3):5-11. DOI: 10.35596/1729-7648-2019-123-5-5-11. (In Russ.)

9. Abramovich N.D., Dick S.K., Vasilevskaya L.A., Khludeyev I.I., Sontea V.P. Methods for assessing the state of microhemocirculation of biotissue by speckle-structure of multiple scattered radiation Journal of Engineering Sciences. 2018;XXV(3):52-60. DOI: 10.5281/zenodo.2557298.