Patent ID: 8457722

Claim:
A device for determining an estimate of body water content, comprising: a processing device configured to process a signal indicative of radiation detected from lean tissue of a patient to compute the estimate of body tissue water content, wherein the estimate is correlative to a computed fractional water content of the lean tissue, wherein the computed fractional water content of the lean tissue (f w l ) is determined such that f w l = [ ∑ n = 1 N ⁢ p n ⁢ ⁢ log ⁢ { R ⁡ ( λ n ) } ] - [ ∑ n = 1 N ⁢ p n ] ⁢ ⁢ log ⁢ { R ⁡ ( λ N + 1 ) } [ ∑ m = 1 M ⁢ q m ⁢ ⁢ log ⁢ { R ⁡ ( λ m ) } ] - [ ∑ m = 1 M ⁢ q m ] ⁢ ⁢ log ⁢ { R ⁡ ( λ M + 1 ) } , and where: p n and q m are calibration coefficients; R(λ) is a measure of the detected radiation at a given wavelength; and n=1−N and m=1−M represent indices for a plurality of wavelengths of the detected radiation which may comprise of the same or different combinations of wavelengths.