METHOD FOR NONINVASIVE DETERMINATION OF BLOOD GLUCOSE CONCENTRATION Russian patent published in 2016 - IPC A61B5/145 A61B5/00 

FIELD: medicine.

SUBSTANCE: biological tissue is exposed successively in any sequence to optical light of the first range at wave lengths 950-970 nm, optical light of the second range at wave lengths 1020-1060 nm, optical light of the third range at wave lengths 930-950 nm, optical light of the fourth range at wave lengths 740-760 nm and optical light of the fifth range at wave lengths 830-850 nm. The optical light diffuse-reflected by the biological tissue is received and transformed into an electrical signal. The blood glucose concentration is determined with the use of an experimental calibration dependence of a glucose concentration and received resultant electrical signal having a value of U_RESULTANT = U₂+U₃+U₅-U₁(k₁₂+k₁₃+k₁₅)-U₄(k₄₂+k₄₃+k₄₅), wherein U₁, U₂, U₃, U₄, U₅ are the electrical signals received when exposing the biological tissue to the optical light of the first, second, third, fourth and fifth ranges, respectively; k₁₂, k₁₃, k₁₅ are coefficients derived in keeping with the expressions k₁₂ = K₂S₂/K₁/S₁, k₁₃ = K₃S₃/K₁/S₁, k₁₅ = K₅S₅/K₁/S₁, wherein K₁, K₂, K₃, K₅ are average water absorption factors in the first, second, third, fourth and fifth wave length ranges, respectively; S₁, S₂, S₃, S₅ are average relative spectral responses of an optical light receiver in the first, second, third, fourth and fifth wave length ranges, respectively; k₄₂, k₄₃, k₄₅ are coefficient pre-derived in keeping with the expressions k₄₂ = K₂S₂/K₄/S₄, k₄₃ = K₃S₃/K₄/S₄, k₄₅ = K₅S₅/K₄/S₄, wherein K₂, K₃, K₄, K₅ are average water absorption factors in the first, second, third, fourth and fifth wave length ranges, respectively; S₂, S₃, S₄, S₅ are average relative spectral responses of an optical light receiver in the second, third, fourth and fifth wave length ranges, respectively.

EFFECT: more accurate blood glucose concentration determination by reducing a measurement uncertainty caused by presence of water and melanin in the analysed biological tissue.

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