CN103385695A - Multi-wavelength liver reserve function detection instrument and ICG (indocyanine green) concentration detection method - Google Patents

Abstract

The invention relates to a multi-wavelength liver reserve function detection instrument and an ICG (indocyanine green) concentration detection method. The detection instrument comprises an embedded microprocessor, a light source driving circuit, a multi-wavelength light-emitting light source, a photoelectric detector, a signal processing circuit, a liquid crystal display, a data memory, a printer and a PC (personal computer) or a browser, wherein the PC or the browser is externally connected. The detection instrument is characterized in that the embedded microprocessor is respectively connected with the power source driving circuit, the signal processing circuit, the liquid crystal display, an SD (secure digital) card, the printer and the PC or the browser; the multi-wavelength light-emitting light source is connected with the light source driving circuit; and the photoelectrical detector is connected with the signal processing circuit. The multi-wavelength liver reserve function detection instrument has the advantages that the changes of arteries, veins and tissues in the pulsation process and the effect on signals by scattering can be simultaneously calculated, and an ICG concentration value, a ICG curve, oxygen saturation degrees of arteries and veins, and other liver function parameters can be obtained, so the detection precision of the ICG concentration and the like can be improved, and the anti-vibration performance is good.

Description

The method of multi-wavelength liver reserve function detector and detection ICG concentration

Technical field

The present invention relates to medical treatment detection device, relate in particular to a kind of method of multi-wavelength liver reserve function detector and detection ICG concentration.

Background technology

Liver is the metabolic hinge of human body,, to the judgement of liver function impairment degree and reserve function, is the focus that people pay close attention to always.To the accurate evaluation of liver function impairment degree and reserve function, very important to the clinical anesthesia safety of liver cirrhosis patient before liver surgery.Preoperative correct assessment liver reserve function, rationally grasp and cut the liver amount in art, is the important measures of avoiding postoperative liver failure.

The mensuration of liver reserve function is the important and popular research topic of liver surgery in recent years, various countries' scholar's research and developed many effective appraisal procedures, for example: the excretion test of indocyanine-green blood collection method, the aminoacid clearance test, the lignocaine clearance test, arterial ketone body ratio is than measuring, oral glucose tolerance test etc., wherein the pigment dilution method that uses of indocyanine-green excretion test is proved to be able to reflect objectively patient's hepatic functional reserve, to the selection of surgical method, opportunity of operation determine have certain effect.But these technology mostly need repeatedly blood drawing after administration, exists larger to patient's wound, method complexity, the problem of time-consuming length.A kind of how to find noinvasive, estimate accurately liver function method just becomes one of important directions of Genneral Surgery.

The principle of pulse oximetry measuring instrument is used for the pigment By Dilution, but the concentration of indocyanine-green in the dual wavelength pulse dye density method noinvasive METHOD FOR CONTINUOUS DETERMINATION arterial blood that development forms, and method is fast and convenient, is suitable for clinical monitoring and uses.By measuring the absorbance ratio at two wavelength places of 805nm/900nm, utilize the pulse spectrophotography just can obtain the concentration ratio of dyestuff indocyanine-green and Hb, the Hb concentration substitution that peripheral blood is recorded just can obtain the concentration of dyestuff indocyanine-green.This method has Wicresoft, the advantage such as easy, real-time, quick, and the product that only has Nihon Kohden Corporation to utilize the method to form at present applies to market.

Existing dual wavelength pulse dye density method has only considered that the absorbance that transmission absorption that arterial pulse causes causes changes; Also there is researcher to consider the variation of arterial oxygen saturation, be about to arterial oxygen saturation and regard variable rather than constant as, proposed to eliminate the three-wavelength method of arterial oxygen saturation impact.But,, owing to all only having considered the arterial pulse variation, do not consider that venous pulsation changes and organize the impact of pulsatile change, do not consider the impact of scattering yet, therefore cause its reliability and certainty of measurement inadequate, measure not accurate enough.

Light in the transmitting procedure of tissue, has stronger scattering effect.

Therefore provide a kind of and consider that not only arterial pulse changes, consider that also venous pulsation changes and organize the impact of pulsatile change, in also considering to detect, scattering is particularly important on detector and the detection method thereof of the impact of signal.

Summary of the invention

The object of the present invention is to provide a kind of arterial pulse variation of not only considering, consider that also venous pulsation changes and organize the impact of pulsatile change, also consider the impact of scattering, record simultaneously: S _a, S _v, V,

And C _dFive unknown quantitys independently, can improve the multi-wavelength liver reserve function detector of the precision of detection and reliability and detect the method for ICG concentration.

The objective of the invention is to be achieved through the following technical solutions:

A kind of multi-wavelength liver reserve function detector, embedded microprocessor are connected with light source driving circuit, signal processing circuit, liquid crystal display, data storage or SD card, printer, PC or browser respectively; The multi-wave length illuminating light source is connected with light source driving circuit; Photodetector is connected with signal processing circuit;

embedded microprocessor is controlled light source driving circuit, pulse train circuit for generating in light source driving circuit inputs to decoder by the square-wave generator clocking, carry out frequency division output 6 tunnel timesharing rectangular signals by decoder, drive respectively the LED of 6 different wave lengths by drive circuit more luminous, photodetector receives the transillumination that sees through tissue and converts the signal of telecommunication to, signal processing circuit is first passed through the one-level processing and amplifying with the signal of telecommunication, again the signal of telecommunication of different wave length is separated, then carry out respectively after filtering and secondary processing and amplifying being input to the A/D converter in embedded microprocessor, A/D converter converts the signal of telecommunication of different wave length to digital signal, embedded microprocessor obtains the ICG concentration value with processing by analysis according to the signal of each wavelength, the ICG curve, arterial oxygen saturation, Svo2 and other liver function parameter, Simultaneous Transmission of Data is to display, printer, PC/browser, and be stored in data storage or SD card.

Detect the method for ICG concentration with multi-wavelength liver reserve function detector, after intravenous injection ICG, use the light of 6 different wave lengths by tissue, survey respectively the light intensity signal of 6 different wave length emergent lights, wherein arbitrary two kinds of different wave length λ _iAnd λ _jThe ratio of pulsating quantity of transillumination be:

${\mathrm{\Φ}}_{\mathrm{ij}}=\frac{{\mathrm{\ΔI}}_i/I_i}{{\mathrm{\ΔI}}_j/I_j}\≈\frac{{\mathrm{\ΔA}}_i}{{\mathrm{\ΔA}}_j}=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z+F)}+\sqrt{({\mathrm{\ϵ}}_V^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_V^i+{\mathrm{\ϵ}}_d^{i}Z+F)}V+E_x^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z+F)}+\sqrt{({\mathrm{\ϵ}}_V^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_V^j+{\mathrm{\ϵ}}_d^{j}Z+F)}V+E_x^i}$

6 different wave lengths have 5 independently light intensity ratio equations, are solved by 5 independent equations: S _a, S _v, V,

And C _dFive unknown quantitys independently;

In formula: i and j represent respectively the sequence number of any two different wave lengths in 6 wavelength,

Φ _ijTwo kinds of wavelength X _iAnd λ _jThe ratio of pulsating quantity of transillumination

,

The variation ratio of two kinds of wavelength absorbances,

ε _a, ε _vAnd ε _dRepresent that respectively wavelength is λ _iOr λ _jThe time arterial blood specific absorbance, venous blood specific absorbance and the light specific absorbance by ICG,

F is light scattering coefficient,

Z=C _d/ C _Hb, C _HbAnd C _dRespectively the concentration of hemoglobin and ICG,

, Δ D _aWith Δ D _vRespectively arterial blood thickness change value and venous blood thickness change value,

With

Be and hemoglobin concentration C _HbAnd tissue, the relevant variable of tremulous pulse varied in thickness, , A _iAnd B _iConstant, Can by

Expression, namely only have

An independent variable;

ε _a=S _aε _O+ (1-S _a) ε _R, ε _v=S _vε _O+ (1-S _v) ε _R, S _aAnd S _vRepresent respectively arterial oxygen saturation and Svo2.

The present invention uses the light of 6 different wave lengths by tissue, surveys respectively the light intensity signal of 6 different wave length emergent lights, utilizes 5 independently light intensity ratio equations, solves simultaneously: S _a, S _v, V,

And C _dFive independently unknown quantity, wherein ICG concentration C _dBe not subjected to the impact of other unknown quantity.

The invention has the beneficial effects as follows: adopt the present invention to consider that not only arterial pulse changes, consider that also venous pulsation changes and organize the impact of pulsatile change, also consider the impact of scattering, can draw in real time, accurately the value of concentration value, ICG curve, arterial oxygen saturation and the Svo2 of ICG, also can obtain simultaneously other liver function parameter, can improve precision and the reliability of detection.

Description of drawings

Fig. 1 is a kind of structured flowchart of multi-wavelength liver reserve function detector;

Fig. 2 is the light source driving circuit structure chart;

Fig. 3 is pulse train circuit for generating structure chart;

Fig. 4 is multi-wave length illuminating light-source structure schematic diagram;

Fig. 5 is the signal processing circuit structure block diagram;

Fig. 6 is multi-wavelength liver reserve function detector software program flow chart.

The specific embodiment

, in order to make purpose of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.

In embodiments of the present invention,, by a kind of multi-wave length illuminating pattern, realized considering simultaneously that arterial pulse variation, venous pulsation change, organize liver reserve function detection method and the device thereof of pulsatile change and diffuse transmission influence.

As shown in Figure 1, a kind of multi-wavelength liver reserve function detector is comprised of embedded microprocessor, light source driving circuit, multi-wave length illuminating light source, photodetector, signal processing circuit, liquid crystal display, data storage or SD card, printer and PC or the browser that connects of being connected.Embedded microprocessor is key control unit.

Embedded microprocessor is connected with light source driving circuit, signal processing circuit, liquid crystal display, data storage or SD card, printer, PC or browser respectively; The multi-wave length illuminating light source is connected with light source driving circuit; Photodetector is connected with signal processing circuit.

With reference to Fig. 2, light source driving circuit consists of pulse train circuit for generating and the drive circuit that is attached thereto.

Pulse train circuit for generating shown in Figure 3 inputs to decoder by the square-wave generator clocking, carry out frequency division output by decoder and produce 6 tunnel timesharing sequence signals, this 6 road sequence signal is by inputing to drive circuit, and the LED timesharing that drives 6 wavelength in multi-wave length illuminating light source shown in Figure 4 is luminous.

Multi-wave length illuminating light source shown in Figure 4 consists of the LED of 6 different wave lengths, and the wave-length coverage of 6 LED is respectively: λ ₁=650nm-680nm, λ ₂=700nm-730nm, λ ₃=750nm-780nm, λ ₄=790nm-810nm, λ ₅=900nm-920nm, λ ₆=930nm-950nm.

With reference to Fig. 5, the one-level amplifying circuit of signal processing circuit connects respectively the multichannel filtering circuit through demultiplexing circuit, and the multichannel filtering circuit connects respectively the multichannel second amplifying circuit.

photodetector shown in Fig. 1 receives the transillumination that sees through tissue and converts the signal of telecommunication to, signal processing circuit shown in Figure 5 is first processed the signal of telecommunication through the one-level amplifying circuit, again the signal of telecommunication of different wave length being carried out signal through demultiplexing circuit separates, then after carrying out filtering and secondary processing and amplifying, filter circuit and second amplifying circuit be input to respectively the A/D converter in embedded microprocessor, A/D converter converts the signal of telecommunication of different wave length to digital signal, embedded microprocessor obtains the concentration value of ICG by analysis according to the signal of each wavelength with processing, the ICG curve, the value of arterial oxygen saturation and Svo2, also can obtain simultaneously other liver function parameter, data can transfer to display simultaneously, printer, PC/browser and be stored in data storage or the SD card in.

With reference to Fig. 6, multi-wavelength liver reserve function detector detects the method for ICG concentration, and detecting step is:

1. start, start embedded system, enter liver reserve function and detect main interface;

2. set up patient files, 6 wavelength detected parameters are set;

3. 6 wavelength image data, gather and finish;

4. date processing, display parameters and curve, print examining report, and data are saved to the data base;

5. whether finish or set up next patient files;

6. finish.

The present invention uses the light of 6 different wave lengths to pass through tissue, consider that not only arterial pulse changes, consider that also venous pulsation changes and organize the impact of pulsatile change, also consider simultaneously the impact of scattering, after intravenous injection ICG, use the light of 6 different wave lengths by tissue, survey respectively the light intensity signal of 6 different wave length emergent lights, wherein arbitrary two kinds of different wave length λ _iAnd λ _jThe ratio of pulsating quantity of transillumination be:

${\mathrm{\Φ}}_{\mathrm{ij}}=\frac{{\mathrm{\ΔI}}_i/I_i}{{\mathrm{\ΔI}}_j/I_j}\≈\frac{{\mathrm{\ΔA}}_i}{{\mathrm{\ΔA}}_j}$

$=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s^j}$

$=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z+F)}+\sqrt{({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^{i}Z+F)V}+E_x^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z+F)}+\sqrt{({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^{j}Z+F)}V+E_x^j}$

6 different wave lengths have 5 independently light intensity ratio equations, are solved by 5 independent equations: S _a, S _v, V, And C _dFive unknown quantitys independently.

Multi-wavelength liver reserve function detection method is specially:

The concentration that blood oxygen saturation is defined as the Oxygenated blood Lactoferrin accounts for the ratio of total hemoglobin concentration, can be similar to formula (1) expression:

${\mathrm{SO}}_2=\frac{C_{O_2\mathrm{Hb}}}{C_{O_2\mathrm{Hb}}+C_{\mathrm{RHb}}}\×100\%---\left(1\right)$

In formula (1), what divide subrepresentation is the concentration of Oxygenated blood Lactoferrin in human body, what denominator represented is the total concentration that contains oxygen and two kinds of hemoglobin of deoxidation in human body, due in hemoglobin concentration, contain two kinds of hemoglobin concentration of oxygen and deoxidation and accounted for the overwhelming majority, while therefore calculating general concentration with the two be approximately equal to total hemoglobin concentration.Blood oxygen saturation is usually as the oxygen supply of passing judgment on patient respiratory and circulation not enough foundation whether on clinical position.

Light transmittance T represents intensity I and the incident intensity I of transillumination _oRatio, as shown in Equation (2).Light transmittance is larger, and the absorption of exponent confrontation incident illumination is fewer; On the contrary, light transmittance is less, and the absorption of exponent confrontation incident illumination is more.

$T=\frac{I}{I_o}---\left(2\right)$

The negative logarithm of light transmittance is called absorbance, with A, represents, sees formula (3).Absorbance is larger, and the absorption of exponent confrontation incident illumination is more.

$A=-\mathrm{lgT}=\lg \frac{I_o}{I}---\left(3\right)$

Material is not only proportional with the thickness of material at the absorbance of certain single wavelength, and also relation in direct ratio of the concentration of solution, and this law is called the Lambert-Beer law.Utilize Lambert-Beer law the applicant to obtain easily content of material and solution concentration by the absorbance of measuring selected wavelength place.

The Lambert-Beer law can represent with formula (4), and wherein, ε is molar absorption coefficient, and C is the concentration of solution, and D is the thickness of material.Can see from formula, the thickness of absorbance and material and the concentration of solution is relation in direct ratio all.

$A=\lg \frac{I_o}{I}=\mathrm{\ϵCD}---\left(4\right)$

The Lambert-Beer law has three prerequisites as follows:

(1) incident illumination is monochromatic light;

(2) do not interact between each material of absorption process;

(3) effect of radiation and material only limits to absorption process, there is no scattering, fluorescence and photochemistry phenomenon.

The pulse spectrophotography is based upon on the basis of Lambert-Beer law.When a monochromic beam saw through tissue, due to the pulse effect, its was absorbed by ripple component material and static component substances simultaneously, formed respectively temporal evolution and the transillumination of two kinds of component substances of temporal evolution not.A current pulse cycle finishes, and when a rear pulse cycle did not also arrive, transillumination was the strongest, reaches peak value, and light intensity note at this moment is direct current light intensity I; Owing to also having the variation of venous blood thickness and tissue thickness, the at this moment variation of transmitted light intensity to be considered in the pulse process except the arterial blood varied in thickness to be irradiated into these varied in thickness materials to cause; And when pulse volume reached maximum, the transmitted light intensity that these variation materials cause was the most weak.The transmitted light intensity that transillumination time to time change in the pulse process, direct current light intensity deduct in the pulse process obtains exchanging light intensity Δ I.

Because causing material varied in thickness Δ D, pulsation causes being changed to of absorbance:

$\mathrm{\ΔA}=\lg \frac{I_0}{I-\mathrm{\ΔI}}-\lg \frac{I_0}{I}=-\lg \frac{I-\mathrm{\ΔI}}{I}=\mathrm{\ϵC\ΔD}---\left(5\right)$

In transillumination, the interchange light intensity Δ I that pulse causes will be much smaller than direct current light intensity I, so:

$\mathrm{\ΔA}=\mathrm{\ϵC\Δ}=-\mathrm{lgD}\frac{I-\mathrm{\ΔI}}{I}=-\lg (1-\frac{\mathrm{\ΔI}}{I})\≈\frac{\mathrm{\ΔI}}{I}---\left(6\right)$

In the pulse process, the variation of thickness is take the arterial blood varied in thickness as main, the variation less of venous blood thickness and tissue thickness.Ignore the variation of venous blood thickness and tissue thickness if only consider the arterial blood varied in thickness, so:

$\mathrm{\ΔA}={\mathrm{\ϵ}}_a{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a\≈\frac{\mathrm{\ΔI}}{I}---\left(7\right)$

Wherein, ε _aFor arterial blood specific absorbance, C _HbFor the concentration of hemoglobin, Δ D _aFor arterial blood thickness change value, as shown in Equation (8):

${\mathrm{\ϵ}}_a=S_a{\mathrm{\ϵ}}_o+(1-S_a){\mathrm{\ϵ}}_R---\left(8\right)$

Wherein, S _aFor arterial oxygen saturation, ε _OAnd ε _RRepresent respectively Oxygenated blood Lactoferrin O ₂Hb and deoxyhemoglobin RHb be at the specific absorbance of monochromatic af at wavelength lambda, and this formula is approximate obtaining on the basis of having ignored a small amount of Carbon monoxide haemoglobin contained in the hemoglobin and metahemoglobin.

Therefore, when a HONGGUANG λ is arranged respectively ₁With an infrared light λ ₂, the pulsating quantity of absorbance is respectively Δ A ₁With Δ A ₂, the ratio of the pulsating quantity of the transillumination of two kinds of wavelength is for as shown in Equation (9):

${\mathrm{\Φ}}_{12}=\frac{{\mathrm{\ΔI}}_1/I_1}{{\mathrm{\ΔI}}_2/I_2}\≈\frac{{\mathrm{\ΔA}}_1}{{\mathrm{\ΔA}}_2}=\frac{{\mathrm{\ϵ}}_a^1}{{\mathrm{\ϵ}}_a^2}=\frac{S_a{\mathrm{\ϵ}}_o^1+(1-S_a){\mathrm{\ϵ}}_R^1}{S_a{\mathrm{\ϵ}}_o^2+(1-S_a){\mathrm{\ϵ}}_R^2}---\left(9\right)$

Wherein arterial oxygen saturation is as shown in Equation (10):

$S_a=\frac{{\mathrm{\Φ\ϵ}}_R^2-{\mathrm{\ϵ}}_R^1}{\mathrm{\Φ}({\mathrm{\ϵ}}_R^2-{\mathrm{\ϵ}}_o^2)+{\mathrm{\ϵ}}_o^1-{\mathrm{\ϵ}}_R^1}---\left(10\right)$

In practical operation, infrared light λ ₂Wavelength of general selection makes

With

Approximately equal, so formula (10) can be simplified to formula (11):

$S_a=a+\mathrm{b\Φ}---\left(11\right)$

If in the pulse process, count simultaneously arterial blood varied in thickness, venous blood varied in thickness and tissue thickness and change, so:

$\mathrm{\ΔA}={\mathrm{\ϵ}}_a{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+{\mathrm{\ϵ}}_v{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+Z_t{\mathrm{\ΔD}}_t\≈\frac{\mathrm{\ΔI}}{I}---\left(12\right)$

Wherein: ε _aFor the arterial blood specific absorbance, Δ D _aFor arterial blood thickness change value, ε _vFor the venous blood specific absorbance, Δ D _vFor venous blood thickness change value, Δ D _tFor tissue thickness's change value, Z _tIt is a constant that almost has nothing to do with incident wavelength.

The prerequisite that the Lambert-Beer law is set up is that light only has absorption process in material, there is no scattering process.And in fact HONGGUANG and infrared light have stronger scattering phenomenon in organism or human body, ignore the scattering process meeting and cause larger error.According to the Schuster principle, introduce Scattering Factors, F is light scattering coefficient, it is all a constant very on a large scale in hemoglobin concentration, so:

$\mathrm{\ΔA}=\sqrt{{\mathrm{\ϵ}}_a({\mathrm{\ϵ}}_a+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{{\mathrm{\ϵ}}_v({\mathrm{\ϵ}}_v+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s\≈\frac{\mathrm{\ΔI}}{I}---\left(13\right)$

Wherein: ε _a=S _aε _O+ (1-S _a) ε _R, ε _v=S _vε _O+ (1-S _v) ε _R, S _aAnd S _vRepresent respectively arterial oxygen saturation and Svo2.Δ A _s=Z _aΔ D _a+ Z _tΔ D _t, Z here _aIt is a constant that almost has nothing to do with incident wavelength.

Two kinds of wavelength X _iAnd λ _jThe ratio of pulsating quantity of transillumination be:

${\mathrm{\Φ}}_{\mathrm{ij}}=\frac{{\mathrm{\ΔI}}_i/I_i}{{\mathrm{\ΔI}}_j/I_j}\≈\frac{{\mathrm{\ΔA}}_i}{{\mathrm{\ΔA}}_j}=\frac{\sqrt{{\mathrm{\ϵ}}_a^i({\mathrm{\ϵ}}_a^i+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{{\mathrm{\ϵ}}_v^i({\mathrm{\ϵ}}_v^i+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s^i}{\sqrt{{\mathrm{\ϵ}}_a^j({\mathrm{\ϵ}}_a^j+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{{\mathrm{\ϵ}}_v^j({\mathrm{\ϵ}}_v^j+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+A_s^j}$

$=\frac{\sqrt{{\mathrm{\ϵ}}_a^i({\mathrm{\ϵ}}_a^i+F)}+\sqrt{{\mathrm{\ϵ}}_v^i({\mathrm{\ϵ}}_v^i+F)}V+E_x^i}{\sqrt{{\mathrm{\ϵ}}_a^j({\mathrm{\ϵ}}_a^j+F)}+\sqrt{{\mathrm{\ϵ}}_v^j({\mathrm{\ϵ}}_v^j+F)}V+E_x^j}$

Wherein:

$V=\frac{{\mathrm{\ΔD}}_v}{{\mathrm{\ΔD}}_a}---\left(15\right)$

${\mathrm{\ϵ}}_a^i=S_a{\mathrm{\ϵ}}_O^i+(1-S_a){\mathrm{\ϵ}}_R^i---\left(16\right)$

${\mathrm{\ϵ}}_v^i=S_v{\mathrm{\ϵ}}_O^i+(1-S_v){\mathrm{\ϵ}}_R^i---\left(17\right)$

$E_x^i=\frac{{\mathrm{\ΔA}}_s^i}{C_{\mathrm{Hb}}{\mathrm{\ΔD}}_a}=\frac{Z_a{\mathrm{\ΔD}}_a+Z_t{\mathrm{\ΔD}}_t}{C_{\mathrm{Hb}}{\mathrm{\ΔD}}_a}=\frac{Z_a}{C_{\mathrm{Hb}}}+\frac{Z_t{\mathrm{\ΔD}}_t}{C_{\mathrm{Hb}}{\mathrm{\ΔD}}_a}---\left(18\right)$

Here

With C _HbAnd tissue, tremulous pulse varied in thickness have relation.

Experiment shows: wavelength for

Impact very little, therefore can represent:

, A here _iAnd B _iConstant, like this

Can by

Expression, namely only have

An independent variable.

After ICG enters human body by intravenous injection, very fast with the hemoglobin speed that reacts.ICG enters calmly hardly after blood in skin, also by its hetero-organization, not absorbed, and the overwhelming majority is by the liver excretion, and vein injects after rear 20 minutes 97% ICG and just by liver, discharged.Survey the absorbance curve of ICG in blood at 800nm wavelength place, the absorbance of finding ICG in blood is subjected to its concentration affects, both present proportional relationship, the sodium chloride of interpolation 0.9% reaches dilution effect in ICG solution afterwards, finds that this proportional relation of solution after dilution still exists.In different normal plasmas, the coefficient of variation of the concentration of ICG is very little, therefore can think that the test of ICG is subjected to pining down of density of plasma albumin hardly.Due to ICG only by the liver excretion, enter blood not with its hetero-organization generation chemical reaction, hemoglobin is for the not obviously impact of mensuration of ICG, and the concentration of ICG and absorbance linear.Can utilize spectrophotography to calculate the concentration of ICG by the absorbance of the ICG of survey, with this, estimate the reserve function of liver.

After intravenous injection ICG, two kinds of wavelength X _iAnd λ _jThe ratio of pulsating quantity of transillumination be:

${\mathrm{\Φ}}_{\mathrm{ij}}=\frac{{\mathrm{\ΔI}}_i/I_i}{{\mathrm{\ΔI}}_j/I_j}\≈\frac{{\mathrm{\ΔA}}_i}{{\mathrm{\ΔA}}_j}$

$=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^i{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_a+\sqrt{({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}})({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^j{C}_d/C_{\mathrm{Hb}}+F)}{C}_{\mathrm{Hb}}{\mathrm{\ΔD}}_v+{\mathrm{\ΔA}}_s^j}$

$=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z+F)}+\sqrt{({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_v^i+{\mathrm{\ϵ}}_d^{i}Z+F)V}+E_x^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z+F)}+\sqrt{({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_v^j+{\mathrm{\ϵ}}_d^{j}Z+F)}V+E_x^j}---\left(19\right)$

Wherein: C _dThe concentration of ICG, Z=C _d/ C _Hb,

With

Respectively two kinds of wavelength X _iAnd λ _jThe specific absorbance of light by ICG.In formula (19), S is arranged _a, S _v, V, And C _dFive unknown quantitys,, if adopt the hepatic functional reserve tester of six wavelength, can list five independently equations by (19) formula, thereby can solve simultaneously S _a, S _v, V,

And C _dFive independently unknown quantity, wherein ICG concentration C _dBe not subjected to the impact of other unknown quantity.

Claims (7)

1. multi-wavelength liver reserve function detector, it is characterized in that: embedded microprocessor is connected with light source driving circuit, signal processing circuit, liquid crystal display, data storage or SD card, printer, PC or browser respectively; The multi-wave length illuminating light source is connected with light source driving circuit; Photodetector is connected with signal processing circuit;

embedded microprocessor is controlled light source driving circuit, the LED timesharing of a plurality of wavelength in the light source driving circuit driving light source is luminous, photodetector receives the transillumination that sees through tissue and converts the signal of telecommunication to, signal processing circuit is first passed through the one-level processing and amplifying with the signal of telecommunication, again the signal of telecommunication of different wave length is separated, then carry out respectively after filtering and secondary processing and amplifying being input to the A/D converter in embedded microprocessor, A/D converter converts the signal of telecommunication of different wave length to digital signal, embedded microprocessor obtains the ICG concentration value with processing by analysis according to the signal of each wavelength, the ICG curve, arterial oxygen saturation, Svo2 and other liver function parameter, Simultaneous Transmission of Data is to display, printer, PC/browser, and be stored in data storage or SD card.

2. multi-wavelength liver reserve function detector as claimed in claim 1, is characterized in that the multi-wave length illuminating light source consists of the LED of 6 different wave lengths, and the wave-length coverage of 6 LED is respectively λ ₁=650nm-680nm, λ ₂=700nm-730nm, λ ₃=750nm-780nm, λ ₄=790nm-810nm, λ ₅=900nm-920nm, λ ₆=930nm-950nm.

3. multi-wavelength liver reserve function detector as claimed in claim 1, is characterized in that light source driving circuit consists of pulse train circuit for generating and the drive circuit that is attached thereto.

4. multi-wavelength liver reserve function detector as claimed in claim 1, is characterized in that the one-level amplifying circuit of signal processing circuit connects respectively the multichannel filtering circuit through demultiplexing circuit, and the multichannel filtering circuit connects respectively the multichannel second amplifying circuit.

5. multi-wavelength liver reserve function detector as claimed in claim 3, the square-wave generator clocking that it is characterized in that the pulse train circuit for generating inputs to decoder, carry out frequency division output 6 tunnel timesharing rectangular signals by decoder, then it is luminous to drive respectively the LED of 6 different wave lengths by drive circuit.

6. detect the method for ICG concentration with multi-wavelength liver reserve function detector claimed in claim 1, it is characterized in that, after intravenous injection ICG, use the light of 6 different wave lengths to pass through tissue, survey respectively the light intensity signal of 6 different wave length emergent lights, wherein any two kinds of different wave length λ _iAnd λ _jThe ratio of pulsating quantity of transillumination be:

${\mathrm{\Φ}}_{\mathrm{ij}}=\frac{{\mathrm{\ΔI}}_i/I_i}{{\mathrm{\ΔI}}_j/I_j}\≈\frac{{\mathrm{\ΔA}}_i}{{\mathrm{\ΔA}}_j}=\frac{\sqrt{({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_a^i+{\mathrm{\ϵ}}_d^{i}Z+F)}+\sqrt{({\mathrm{\ϵ}}_V^i+{\mathrm{\ϵ}}_d^{i}Z)({\mathrm{\ϵ}}_V^i+{\mathrm{\ϵ}}_d^{i}Z+F)}V+E_x^i}{\sqrt{({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_a^j+{\mathrm{\ϵ}}_d^{j}Z+F)}+\sqrt{({\mathrm{\ϵ}}_V^j+{\mathrm{\ϵ}}_d^{j}Z)({\mathrm{\ϵ}}_V^j+{\mathrm{\ϵ}}_d^{j}Z+F)}V+E_x^i}$

6 different wave lengths have 5 independently light intensity ratio equations, are solved by 5 independent equations: S _a, S _v, V,

And C _dFive unknown quantitys independently;

In formula: i and j represent respectively the sequence number of any two different wave lengths in 6 wavelength,

Φ _ijTwo kinds of wavelength X _iAnd λ _jThe ratio of pulsating quantity of transillumination

,

The variation ratio of two kinds of wavelength absorbances,

ε _a, ε _vAnd ε _dRepresent that respectively wavelength is λ _iOr λ _jThe time arterial blood specific absorbance, venous blood specific absorbance and the light specific absorbance by ICG,

F is light scattering coefficient,

Z=C _d/ C _Hb, C _HbAnd C _dRespectively the concentration of hemoglobin and ICG,

, Δ D _aWith Δ D _vRespectively arterial blood thickness change value and venous blood thickness change value,

With Be and hemoglobin concentration C _HbAnd tissue, the relevant variable of tremulous pulse varied in thickness,

, A _iAnd B _iConstant,

Can by

Expression, namely only have

An independent variable;

ε _a=S _aε _O+ (1-S _a) ε _R, ε _v=S _vε _O+ (1-S _v) ε _R, S _aAnd S _vRepresent respectively arterial oxygen saturation and Svo2.

7. use as claimed in claim 6 multi-wavelength liver reserve function claimed in claim 1 detector detects the method for ICG concentration, it is characterized in that detecting step is:

1. start, start embedded system, enter liver reserve function and detect main interface;

2. set up patient files, 6 wavelength detected parameters are set;

3. 6 wavelength image data, gather and finish;

4. date processing, display parameters and curve, print examining report, and data are saved to the data base;

5. whether finish or set up next patient files;

6. finish.

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