BG110931A - A method and a device for a non-invasive determination of the blood sugar level - Google Patents

Abstract

The method and the device find application in medicine, more specifically for the diagnosis of diabetic state. The method and the device allow the patient to non-invasively measure every day his/her blood sugar without physicianÆs intervention. The crux of the method is that discrete quasimonochromatic sources of light (4) are consecutively scanned by a generator (2) of pulses whose parameters can be regulated. The pulse radiation hits the studied body tissue (5), so that the passed part and the reflected part of the radiation fall upon a photoreceiver for the one (6) and the other part (7), respectively. The two signals are intensified by a differential amplifier (8). The amplified difference is compared for every wavelength to gauged reference values of blood sugar at different levels of sugar in patientÆs organism determined by an invasive method. These reference values are kept in an individual invasive data basis in the organized memory of the device (12) accomplishing the method.

Description

Technical field

The invention relates to a method and device for the non-invasive determination of blood sugar, which will find application in medicine and in particular in the diagnosis of diabetic conditions.

BACKGROUND OF THE INVENTION

Non-invasive methods using near infrared and Raman spectroscopy, polarimetry, light scattering as it passes through tissues, photoacoustic spectroscopy, mean infrared spectroscopy, etc. are known.

Devices are known to use methods for performing absorption analysis of passing light, and detection of a sugar-only signal is quite difficult. The absorption of the radiated spectrum that passes through the skin tissue is not only affected by water, albumin, globulin, hemoglobin, and triglycerides, but also by the environment, by factors such as body temperature and vapor levels. In addition, the blood of different people contains different amounts of protein, water and fat. The actual measurement of blood sugar by absorption in the visible and near-infrared region has problems with different levels of protein and fat absorption.

Closest to the proposed method and device is the technical solution of the publication of patent US 6675030 B2. A high-intensity polychromatic source emits light at the monochromator inlet. A monochromator is a device in which the incoming light from the source, using a prism, is decomposed into separate monochromatic lines. From the output of the monochromator, the resulting monochromatic light in the visible and near infrared spectra is sent to the test specimen, which forms part of the human body. The method uses two paths to analyze the interacting monochromatic light with the sample. In the first, the transmitted light is received by a photodetector by analyzing the dependence of the photocurrent on the wavelength and the irradiation time of the sample. In the second, the reflected light from the sample is received and analyzed by the photodetector.

Depending on the non-invasive individualized spectral scans of the part of the body, as well as the analysis of independent blood samples from the patient obtained from invasive methods, an individual database of the patient is made on a central computer located at the attending physician. Once entered, these data serve the physician to determine the patient's condition further only with the non-invasive spectral method and device.

The disadvantage of the method and the device is that non-invasive results are obtained with the help of an expensive monochromator device, where working with it requires specialized knowledge of spectral technique by the attending physician.

The patient can only go to the attending physician, who must have this expensive equipment, do a series of invasive examinations to enter as a database into a central computer, and then visit the doctor's office for non-invasive monitoring every day.

SUMMARY OF THE INVENTION · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

It is an object of the invention to provide a method for the non-invasive determination of blood sugar that is of lower cost and accessible to the general public by conducting the study in a non-invasive, painless manner at home.

The method is that discrete quasi-monochromatic light sources are scanned sequentially by a pulse generator of a predetermined duration. The set of quasi-monochromatic sources is selected to cover the range of the ultraviolet, visible and near-infrared regions discreetly but sufficiently tightly for the purpose of the method. Pulse radiation, which can be adjusted in frequency, period and intensity to maximize the effect, falls on the body tissue under study so that both the passed part and the reflected part of the radiation fall into the photodetectors. Both signals are extracted by differential amplification, thus eliminating continuous changes in the patient's skin caused by external factors. After amplification, the signal is compared for each wavelength with calibration benchmarks of blood sugar at different levels of sugar in the patient's body, obtained by the invasive method. These benchmarks are stored in an individual disposable invasive database in the organized memory of the device executing the method. This method and device allow, after calibration of the device, through this individual database, the patient can measure their blood sugar non-invasively every day without the need for medical intervention.

The method implementation device consists of quasi-monochromatic sources with a half-width of spectrum of about 50 nm-super luminescent LEDs in the following emission areas: -violet, violet, blue, green, yellow, orange, red, infra-red, white (poly-red, white) ), which are coupled to a scanning generator that can set both the amplitude of the emitted signal to each LED individually and the radiation duration and generation period accurately. The LEDs are located in a holder so that each of their optical focuses falls at the same point of the irradiated object (finger, auricle). The resulting, reflected signal from the irradiated object and the signal passed through the object are received by photodetectors (PIN photodiodes) located in the device.

The photodetectors are connected to a differential amplifier powered by a stabilized voltage source. The photocurrents obtained are compared for each wavelength with blood glucose calibration benchmarks stored in an individual invasive organized memory (EEPROM) database of the device. This data is served by a built-in PIC controller. The measured values are displayed on the LCD. The device is intended to generate a warning light and sound signal at critical blood glucose values.

The advantages of the invention are that no monochromatic radiation produced by decomposition of polychromatic light is used.

·· · • · · · · · · monochromator, where it regulates frequency, a the intensity of the radiation.fe mag1 ;; ^ 1 it is impossible to use quasi monochromatic superluminescent

discrete sources of varying wavelengths powered by a pulse generator with adjustable width, amplitude and frequency that make the device accessible to the general public because of the expected low cost and that the proposed method and device allow the measurement of blood glucose. diabetic and pre-diabetic patients in a non-invasive, painless manner at home. The invention overcomes the stress and fear of daily adoration of the fingers, enabling the measurement of blood sugar to be performed at any time and where necessary.

Description of the attached figures

An exemplary embodiment of the invention is shown in the accompanying figure, wherein;

Figure 1 is a schematic diagram of the device.

An exemplary embodiment of the invention

The essence of the method for non-invasive blood glucose determination according to Figure 1 is expressed in the following.-Powered by a stabilized voltage source 1 pulse generator 2, with set amplitude, period and pulse duration, scans sequentially superluminescent quasimonochromatic 4 The radiation of each source is directed to a part of the human body 5, which may be a finger or mucous membrane of the auricle, its passed part being received by a photodetector for the past radiation 6, and in the same the reflected part of the time is received by the photodetector for the reflected radiation 7. The differential amplifier 8 receives and amplifies the difference between the reflected and the transmitted signals by submitting them for processing to the PIC controller 9, which is a single-chip computer. For each patient in the doctor's office, a profile of the various possible blood glucose levels is invoked once with the invasive method 10, which is a standard procedure for determining who is diabetic. For each measured blood glucose level with the invasive method, a record in memory 11 of the amplified by 8 difference of the photo signals from the two photodetectors 6 and 7 is parallelized. These recorded values serve for calibration benchmarks with which the PIC controller 9 compares subsequent measurements with non-invasive method to display 12 amounts of blood sugar in the display. For critical blood glucose values, the built-in generator 13 includes a light and sound warning signal.

The device operating according to the predetermined method according to Figure 1 is composed of a stabilized voltage source 1, which ensures the normal operation of the individual units of the device connected to the pulse generator 2, with a predetermined amplitude, period and duration of the pulses, which scans sequentially over time, superluminescent quasi-monochromatic sources 4 that are mounted in holder 3 so that the focus of the radiation of each source falls at one point on the irradiated portion of the human body 5. They are attached to the holder 3 and two photodetectors, respectively, a photodetector for the past radiation 6 and a photodetector for the reflected radiation 7. The photodetector for the past h::: ··· .. ·: ·:

radiation 6 is mounted so that TRIMA only. during 5 radiation, and the photodetector for reflected radiation 7 is mounted so that it only receives the radiation reflected by the irradiated part 5. The two photodetectors 6 and 7 are connected to a differential amplifier 8 so that the amplified difference from the output of the amplifier is fed to the input of the PIC controller 9 for processing and comparison with a blood glucose database in memory 11, which is connected to the output of the controller 9. After processing, the PIC controller 9 shows the measured amount of blood sugar on the LCD 12 connected to it and mounted on the front panel of the device. A light and sound generator 13 is also connected to the controller 9, which is triggered at critical blood glucose values.

Claims (2)

Claims * claims 1. A method for the non-invasive determination of blood sugar in which electromagnetic current in the visible and near part of the spectrum passes or is reflected by the investigated object representing the frequency-human-body, and the received signals are compared with an invasive database located in the memory of a computer, characterized in that it is powered by a stabilized voltage source / 1 / impulse generator / 2 /, with set duration, period and pulse amplitude, scans superluminescent quasimonochro sequentially parent sources / 4 /, thus producing powerful pulses of light with a set frequency, repetition period and intensity for maximum effect, directing the radiation of each source to a part of the studied object / 5 / by the human body, at which is often received by the received radiation from a photodetector for the received radiation 161, while its reflected part is simultaneously received by the photodetector for the reflected radiation (7) and by a differential operating amplifier (8), as the difference between the reflected and the transmitted signals with receives, amplifies, and submits to the input of a PIC controller / 9 / that uses calibration benchmarks recorded in advance with an invasive method in memory / 11 / and compares them to the input signals from the output of the operational amplifier / 8 / with them, showing on the display / 12 / blood glucose levels, as at critical blood glucose values, an audible warning signal from the generator / 13 / is activated. A device for carrying out the method according to claim 1, characterized in that it consists of a stabilized voltage source (1) connected to a pulse generator (2), with a predetermined amplitude, period and duration of pulses serving for sequential scanning over time of superluminescent quasi-monochromatic sources (4) mounted in a holder (3) such that the focus of the radiation of each source is at one point on the irradiated part of the investigated object (5) by the human body, such as to the holder / 3 / is attached a fixed photodetector for the transmitted radiation 161 and a photodetector for the reflected radiation (7), the two photodetectors (6), (7) being connected to a differential amplifier (8), which is connected to the input of the PIC controller 9 with an interpolation program integrated therein, for processing and comparing with an invasive blood sugar database stored in memory / 11 / that is connected to the output of the controller / 9 /, where after processing the PIC controller / 9 / the measured amount of blood sugar is reflected on the liquid crystal display / 12 / connected to it and mounted to it the whole panel of the device, and for critical values of blood sugar an integrated generator / 13 / is emitted, emitting a warning light and sound signal. • · · A method and device for non-invasive blood glucose determination will find application in medicine and in particular in the diagnosis of diabetic conditions. Discrete quasi-monochromatic light sources / 4 / are scanned sequentially by an impulse generator / 2 / with set parameters. The impulse radiation falls on the examined tissue from the body (5) so that both the passed part and the reflected part of the radiation fall into the photodetector for the received radiation (6) and the photodetector for the reflected radiation (7). Both signals are amplified by a differential amplifier / 8 /. The amplified difference is compared for each wavelength with blood glucose calibration benchmarks at different levels of patient sugar obtained by the invasive method. These benchmarks are stored in an individual disposable invasive database in the organized memory of the device (12) performing the method. This method and device allow, after calibration of the device, through this individual database, the patient can measure their blood sugar non-invasively every day without the need for medical intervention.