Method and system for use in non-invasive optical measurements of blood parameters
First Claim
1. A method for use in non-invasive optical measurements in a patient'"'"'s body, the method comprising:
- (a) creating a condition of artificial blood kinetics at a measurement location in a patient'"'"'s blood perfused fleshy medium and maintaining this condition for a certain time period, the creation of the artificial blood kinetics comprising applying primary over-systolic pressure to achieve a state of temporary blood flow cessation in the medium at the measurement location, the primary over-systolic pressure being applied either to a certain location upstream of the measurement location with respect to a normal blood flow direction in the medium or to the vicinity of the measurement location;
(b) altering said condition of artificial blood kinetics at the measurement location over a predetermined time interval within said certain time period so as to modulate an optical response by changing scattering properties of blood, said altering of the condition of artificial blood kinetics including applying a perturbation to the medium by at least one secondary pressure pulse of a predetermined value over said predetermined time interval; and
(c) applying optical measurements to the measurement location by illuminating the measurement location with incident light beams of at least two different wavelengths in a range where the light radiation is sensitive to scattering properties of blood, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval.
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Accused Products
Abstract
A method and device are presented for use in non-invasive optical measurements of at least one desired characteristic of patient'"'"'s blood. A condition of artificial blood kinetics is created at a measurement location in a patient'"'"'s blood perfused fleshy medium and maintained for a certain time period. This condition is altered over a predetermined time interval within said certain time period so as to modulate scattering properties of blood. Optical measurements are applied to the measurement location by illuminating it with incident light beams of at least two different wavelengths in a range where the scattering properties of blood are sensitive to light radiation, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval.
198 Citations
43 Claims
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1. A method for use in non-invasive optical measurements in a patient'"'"'s body, the method comprising:
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(a) creating a condition of artificial blood kinetics at a measurement location in a patient'"'"'s blood perfused fleshy medium and maintaining this condition for a certain time period, the creation of the artificial blood kinetics comprising applying primary over-systolic pressure to achieve a state of temporary blood flow cessation in the medium at the measurement location, the primary over-systolic pressure being applied either to a certain location upstream of the measurement location with respect to a normal blood flow direction in the medium or to the vicinity of the measurement location; (b) altering said condition of artificial blood kinetics at the measurement location over a predetermined time interval within said certain time period so as to modulate an optical response by changing scattering properties of blood, said altering of the condition of artificial blood kinetics including applying a perturbation to the medium by at least one secondary pressure pulse of a predetermined value over said predetermined time interval; and (c) applying optical measurements to the measurement location by illuminating the measurement location with incident light beams of at least two different wavelengths in a range where the light radiation is sensitive to scattering properties of blood, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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11. A method for use in non-invasive optical measurements of at least one desired characteristic of patient'"'"'s blood, the method comprising:
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(a) creating a condition of artificial blood kinetics at a measurement location in a patient'"'"'s blood perfused fleshy medium and maintaining this condition for a certain time period, the creation of the artificial blood kinetics comprising applying primary over-systolic pressure to achieve a state of temporary blood flow cessation in the medium at the measurement location, the primary over-systolic pressure being applied either to a certain location upstream of the measurement location with respect to a normal blood flow direction in the medium or to the vicinity of the measurement location; (b) altering said condition of artificial blood kinetics at the measurement location over a predetermined time interval within said certain time period so as to modulate scattering properties of blood, said altering of the condition of artificial blood kinetics including applying perturbations to the medium by secondary pressure of a predetermined cyclic pattern over said predetermined time interval; and (c) applying optical measurements to the measurement location by illuminating the measurement location with incident light beams of at least two different wavelengths in a range where the light radiation is sensitive to scattering properties of blood, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29)
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30. A method for use in non-invasive optical measurements in a human body, the method comprising:
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applying a primary over-systolic pressure to a patient'"'"'s blood perfused fleshy medium at a location in vicinity of a measurement location to thereby create a condition of artificial blood kinetics at the measurement location, and maintaining this condition for a certain time period; varying the over-systolic pressure in the vicinity of the measurement location by applying, over a predetermined time interval, a perturbation to the medium by at least one secondary pressure pulse of a predetermined profile, starting from said primary over-systolic pressure value, thereby altering said condition of artificial blood kinetics at the measurement location over said predetermined time interval within said certain time period so as to modulate scattering properties of blood; and applying optical measurements to the measurement location by illuminating the measurement location with incident light beams of at least two different wavelengths in a range where the light radiation is sensitive to scattering properties of blood detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium for said at least two different wavelengths, respectively, over at least a part of said predetermined time interval.
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31. An optical system for use in non-invasive optical measurements in a human body, the system comprising:
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(A) a probe including;
(i) two substantially U-shaped portions configured for enclosing and holding a portion of the patient'"'"'s flesh medium therebetween and carrying an optical measuring unit operable for illuminating a measurement location on a patient'"'"'s blood perfused flesh medium with different wavelengths of incident light, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium corresponding to the different wavelengths of incident light, respectively; and
(ii) a pressurizing assembly operable for applying pressure to the patient'"'"'s fleshy medium, the pressurizing assembly comprising a drive assembly operable to move the U-shaped portions towards one another, and thereby apply the primary and secondary pressure to the portion of the medium enclosed therebetween;(B) a control unit connectable to said measuring unit and said pressurizing assembly for synchronizing the operation thereof so as to apply a primary over-systolic pressure to a certain location on the medium to create a condition of artificial blood kinetics in the medium at the measurement location and maintain this condition for a certain time period, to apply a secondary controllably varying pressure to the fleshy medium in the vicinity of the measurement location so as to alter said condition of artificial blood kinetics over a predetermined time interval within said certain time period thereby modulating scattering properties of blood, and to apply the optical measurements while altering the condition of the artificial blood kinetics, the control unit comprising;
(a) a memory for storing reference data sensitive to patient individuality and indicative of a desired blood characteristic as a function of a parameter derived from scattering spectral features of the medium, and (b) a data acquisition and processing utility coupled to output of the measuring unit for receiving and analyzing the measured data to utilize the reference data and determine said at least one desired blood characteristic. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39)
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40. A probe for use in non-invasive optical measurements in a human body, the probe including:
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(a) two substantially U-shaped portions configured for enclosing and holding a portion of a patient'"'"'s blood perfused flesh medium therebetween and being driven to move one towards the other, (B) a measuring unit operable for illuminating a measurement location on the portion of the medium with different wavelengths of incident light beams, detecting light responses of the medium, and generating measured data indicative of time evolutions of the light responses of the medium corresponding to the different wavelengths of incident light, respectively; and (C) a pressurizing assembly associated with at least one of the U-shaped portions and operable for moving the U-shaped portion one towards the other to thereby apply a primary over-systolic pressure to the fleshy medium so as to create a condition of artificial blood kinetics in the fleshy medium and maintain this condition for a certain time period and to apply a secondary controllably varying over-systolic pressure to the fleshy medium, so as to alter said condition of artificial blood kinetics over a predetermined time interval within said certain time period, thereby to modulate scattering properties of blood. - View Dependent Claims (41, 42, 43)
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Specification