Blood culture detection system based on spectral reflectance technology and alarm method thereof

Abstract

This invention discloses a blood culture detection system based on spectral reflectance technology, comprising: a culture container for culturing samples; a sensor for sensing the sample state and changing color according to changes in the sample state; a light signal acquisition component for projecting single-wavelength light onto the sensor and receiving the reflected light signal after reflection by the sensor; and a reading module for obtaining a reading result indicating whether the sample is infected based on the received reflected light signal; the light source is used to project at least two different colors of single-wavelength light onto the sensor. This invention also discloses an alarm method for the blood culture detection system based on spectral reflectance technology. The blood culture detection system and alarm method of this invention, based on spectral reflectance technology, improve the accuracy of positive rate readings by using different wavelength light sources for detection.

Description

Technical Field

[0001] This invention belongs to the field of in vitro detection technology, specifically a blood culture detection system and its alarm method based on spectral reflectance technology. Background Technology

[0002] The principle of blood culture analysis is to qualitatively detect the presence of microorganisms by monitoring changes in turbidity, pH, CO2 concentration of metabolic products, and fluorescently labeled substrates or metabolic products in the culture medium (liquid). Based on different detection principles, it can be divided into four types: colorimetric, fluorescence, barometric, and electrode methods. Currently, the mainstream method is colorimetry. In colorimetry, a sensor is placed at the bottom of each culture bottle, and a semi-permeable silica membrane is placed between the culture medium and the sensor. Only CO2 can pass through this semi-permeable silica membrane. When microorganisms grow in the blood culture bottle, the released CO2 permeates to the sensor. After water saturation, it produces H+, changing the sensor's pH value and causing a color change from blue-green to yellow. As the CO2 concentration increases, the sensor's color becomes lighter, and the reflected light becomes stronger (the lighter the color, the higher the "reflectance unit" value). Therefore, in colorimetry, the presence of microbial growth can be determined by color changes.

[0003] The general method for detecting infection in blood involves culturing the blood and monitoring changes in the culture medium. If the growth of microorganisms in the culture medium exceeds the standard value, it indicates infection. The monitoring method typically involves an LED light source projecting light onto a sensor, and a photodiode detecting the reflected light. As the CO2 concentration increases, the sensor becomes lighter, the reflected light becomes stronger, and the lighter the color, the higher the reflectance unit value. Different reflectance units are obtained over time. By comparing the initial reflectance units with the current reflectance units, a positive result (i.e., whether the blood sample is infected) is determined. If, after a certain number of days, the CO2 level does not change significantly, the instrument will report the culture bottle as negative.

[0004] However, when the sensor's color change is small, the change in reflectance is small, resulting in low response sensitivity. Clinically, this manifests as poor sensitivity to weakly growing bacteria, leading to false negatives and affecting the accuracy of the positive rate. Furthermore, environmental changes causing curve fluctuations can also impact accuracy. Current technologies typically improve accuracy by increasing response sensitivity, such as enhancing the sensor's sensitivity to CO2 or pH, but none of these methods consider the influence of the light source on accuracy. Summary of the Invention

[0005] Existing technologies all use single-wavelength LED light sources. Experimental verification has revealed two issues: First, when the color change of the sensor is small, the change in reflectance is small, resulting in low response sensitivity. Clinically, this manifests as poor sensitivity to weakly growing bacteria, easily leading to false negatives and affecting the accuracy of positive rate interpretation. Second, when environmental changes cause curve fluctuations, single-wavelength LED light source detection is prone to false positives, also affecting the accuracy of positive rate interpretation. Therefore, single-wavelength LED light source detection cannot adapt to a wide range of reflective substrates, and the reflectance data from a single-wavelength LED light source has limitations for interpretation.

[0006] In view of this, the purpose of the present invention is to provide a blood culture detection system and its alarm method based on spectral reflectance technology, which improves the accuracy of positive rate interpretation by using different wavelength light sources for detection.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention first proposes a blood culture detection system based on spectral reflectance technology, comprising:

[0009] Culture containers are used to culture samples;

[0010] A sensor used to sense the state of a sample and change color as the state of the sample changes.

[0011] An optical signal acquisition component is used to project a single wavelength of light onto the sensor and to receive the reflected light signal after it has been reflected by the sensor.

[0012] The interpretation module is used to determine whether the sample is infected based on the received reflected light signal;

[0013] The optical signal acquisition component is used to project at least two different colors of single wavelength light onto the sensor.

[0014] Furthermore, the interpretation module obtains the interpretation result of whether the sample is infected based on the reflection signal parameters of the single wavelength light.

[0015] Furthermore, the reflected signal parameters are reflected signal parameters that can reflect changes in the sensor's color, including but not limited to at least one of the following: intensity of the reflected signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

[0016] Furthermore, the interpretation module outputs a result determining whether a sample is infected based on whether the reflection signal parameters of all N single-wavelength lights reach a set threshold: if the reflection signal parameters of N1 single-wavelength lights reach the set threshold, a preliminary positive interpretation result is obtained and displayed; within the verification time range, if the reflection signal parameters of another N2 single-wavelength lights reach the set threshold, a positive interpretation result is obtained and displayed; if the reflection signal parameters of another N3 single-wavelength lights do not reach the set threshold, a negative interpretation result is obtained; where: N1+N2≤N; N1+N3≤N; N1≤N3; N3>N / 2; Q≥N-N1-N2+1.

[0017] Furthermore, the interpretation module outputs a result to determine whether the sample is infected based on whether the reflection signal parameter of any single wavelength light reaches a set threshold: if the reflection signal parameter of a single wavelength light reaches the set threshold, a preliminary positive interpretation result is obtained and displayed; if the reflection signal parameters of all single wavelength lights do not reach the set threshold during the sample culture period, a negative interpretation result is obtained.

[0018] Furthermore, when the interpretation module obtains a preliminary positive interpretation result, it records and displays the preliminary positive interpretation time.

[0019] Furthermore, the interpretation module is configured to, after obtaining a preliminary positive interpretation result, also determine whether to end the detection or continue the detection based on the acquired reflected light signal.

[0020] Furthermore, during the continued detection process, if the interpretation module obtains a positive interpretation result based on the reflection signal parameters of other single-wavelength light, it outputs and displays the positive interpretation result; if, until the end of the culture time, the interpretation module obtains a negative interpretation result based on the reflection signal parameters of other single-wavelength light, the preliminary positive interpretation result is corrected to a negative interpretation result.

[0021] Furthermore, before continuing to acquire light signals, the method also includes: determining whether the culture container has been removed; if the culture container has been removed, the detection ends; if the culture container has not been removed, the reflected light signal continues to be acquired, and the interpretation module confirms whether to end the detection or continue the detection based on the reflected light signal.

[0022] Furthermore, after the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of the corresponding single wavelength light, it initiates the first verification procedure;

[0023] The first verification period is defined as the first set time period after the interpretation module obtains the preliminary positive interpretation result. During the first verification period, the interpretation module verifies the preliminary positive interpretation result based on whether the reflection signal parameters of other single wavelength light reach a threshold. If the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single wavelength light, the preliminary positive interpretation result is eliminated. If the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of any other single wavelength light, a positive interpretation result is obtained, and the verification ends.

[0024] Furthermore, if the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single-wavelength light, a second verification procedure is initiated during the continued verification of the sample. The second verification period is defined as the second set time period after the first verification time period. During the second verification time period, if a preliminary positive interpretation result is obtained again based on the reflection signal parameters of the single-wavelength light from which the preliminary positive interpretation result was obtained, the interpretation module obtains a positive interpretation result, and the verification ends. Otherwise, the sample continues to be verified until the end of the second verification time period.

[0025] Furthermore, the optical signal acquisition component includes a light source and a receiver. The light source is used to project a single wavelength of light onto the sensor, and the receiver is used to receive the reflected light signal after being reflected by the sensor.

[0026] Furthermore, the light source is a single light source capable of emitting at least two different colors of single wavelength light; or, the light source includes a single light source capable of emitting white light and at least two filters capable of transmitting single wavelength light of different colors; or, the light source includes at least two light-emitting units, and different light-emitting units are capable of emitting single wavelength light of different colors.

[0027] Furthermore, the light source is a ring-shaped light source installed around the perimeter of the installation space, and the ring-shaped light source is provided with at least two light-emitting units, each of which can emit a single wavelength of light of a different color.

[0028] Furthermore, it also includes a container placement module, which includes a cavity for placing the culture container and an installation space for installing the optical signal acquisition component; the sensor is disposed at the bottom of the culture container.

[0029] This invention also proposes an alarm method for a blood culture detection system based on spectral reflectance technology, comprising the following steps:

[0030] S1: N different colors of single wavelength light are sequentially projected onto a sensor located at the bottom of the culture container using a light source. When the light source projects the i-th single wavelength light onto the sensor, the receiver receives the i-th reflected light signal after the i-th single wavelength light is reflected by the sensor. Where N≥2.

[0031] S2: Determine whether the reflection signal parameters of the i-th reflected light signal have reached the set threshold: if yes, obtain and display the preliminary positive interpretation result, and execute S3; if no, execute S6.

[0032] S3: Determine if the culture container has been removed: if yes, the detection ends; if no, start the verification program and execute S4.

[0033] S4: Use a light source to sequentially project N different colors of single wavelength light onto a sensor located at the bottom of the culture container; and when the light source projects the i-th single wavelength light onto the sensor, use a receiver to receive the i-th reflected light signal after the i-th single wavelength light is reflected by the sensor; where N≥2;

[0034] S5: Within the first verification time, determine whether the reflection signal parameter of any single wavelength light other than the i-th single wavelength light reaches the set threshold: if yes, obtain and display the positive judgment result and end the detection; if no, eliminate the preliminary positive judgment result and execute S6.

[0035] S6: Determine if the sample culture is complete: If yes, the test ends and a negative result is obtained and displayed; if no, proceed to S4.

[0036] Furthermore, the reflected signal parameters are reflected signal parameters that can reflect changes in the sensor's color, including but not limited to at least one of the following: intensity of the reflected signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

[0037] Furthermore, the light source is a single light source capable of emitting light of a single wavelength in at least two different colors; or,

[0038] The light source includes a single light source capable of emitting white light and at least two filters capable of transmitting single wavelengths of light of different colors, wherein the filters are controlled to pass through the light source in turn; or,

[0039] The light source includes at least two light-emitting units, each of which is capable of emitting a single wavelength of light of a different color.

[0040] The beneficial effects of this invention are as follows:

[0041] This invention relates to a blood culture detection system based on spectral reflectance technology. By setting the light source to project at least two different colors of single-wavelength light onto the sensor, the interpretation module can use the reflected light signals of at least two different colors of single-wavelength light to obtain the interpretation result of whether the sample is infected, thereby improving the accuracy of the positive rate interpretation. The reasons are as follows:

[0042] (1) When the color change of the sensor is small, since at least two different colors of single wavelength light are used, during the sample culture process, as the color of the sensor changes, at least one single wavelength light is close to or even the same as the color of the reactor. Thus, according to the principle of spectral reflection, light of similar or the same color (light with the same or similar wavelength) has a higher reflectance, which can increase the unit change in reflectance and thus improve the response sensitivity. Clinically, this means that it can improve the response sensitivity to weakly growing bacteria. On the one hand, it can improve the efficiency of preliminary positive interpretation, so that patients can receive timely treatment. On the other hand, it can also avoid false negative interpretation and improve the accuracy of positive rate interpretation.

[0043] (2) After obtaining a preliminary positive result, the preliminary positive result can be verified by using single wavelength light of other colors to improve the accuracy of the positive rate. In particular, when the environment changes, the reflected light information curve of a single wavelength light of a certain color may fluctuate, which may lead to a false positive result. However, for single wavelength light of other colors, the environmental change has little effect on the reflected light information curve and will not lead to a false positive result. In this way, by combining the reflected light information of single wavelength light of at least two colors, the influence of environmental change on the accuracy of the positive rate can be avoided. Attached Figure Description

[0044] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration:

[0045] Figure 1 This is a diagram illustrating the principle of spectral reflectance of a red object.

[0046] Figure 2 The spectral reflectance curves of objects of different colors are shown; (a) red object; (b) blue object; (c) green object.

[0047] Figure 3 This is a schematic diagram of the structure of an embodiment 1 of a microbial culture unit;

[0048] Figure 4 This is a graph showing how reflectance changes over time.

[0049] Figure 5 This is a flowchart of a blood culture detection method based on spectral reflectance technology.

[0050] Explanation of reference numerals in the attached figures:

[0051] 1-Cultivation container; 2-Installation space; 3-Sensor; 4-Receiver; 5-Light-emitting unit. Detailed Implementation

[0052] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0053] Principle of Spectral Reflection: The selective absorption and reflection of light by an object can be expressed by a spectral reflectance curve. The ratio of the luminous flux reflected by the object to the luminous flux incident on the object is the relationship curve between light reflectance and wavelength. The spectral reflectance curve of an object reflects the comprehensive characteristics of that object, including its selective absorption of incident light, light scattering, and specular reflection from its surface. Figure 1 The reason why the red object shown is red is that when light from a light source reaches the object's surface, due to the object's own properties, it absorbs blue, green, and yellow light, but not red light. The unabsorbed red light is reflected back and reaches the observer, so the observer can only see the reflected red light, thus making the object appear red. This is the process by which an object exhibits its surface color.

[0054] Since the property of an object regarding color is the selective absorption of electromagnetic waves of different wavelengths, we use spectral reflectance curves to express this property. For example... Figure 2 As shown, red objects have relatively low reflectivity for short wavelengths, meaning they absorb blue and yellow light; blue objects have relatively low reflectivity for long wavelengths, meaning they absorb yellow and red light; and green objects have relatively low reflectivity for both long wavelengths (red and yellow light) and short wavelengths (blue light). For the same object, the spectral reflectivity curves are different depending on the light source reaching its surface. For example, when a blue object is illuminated by a red light source, its spectral reflectance curve is low across the entire wavelength range; when illuminated by a green light source, its spectral reflectance curve is low across the entire wavelength range; when illuminated by a blue light source, its spectral reflectance curve is high in the short wavelength range; when illuminated by a red light source, its spectral reflectance curve is low across the entire wavelength range; when illuminated by a green light source, its spectral reflectance curve is high in the mid-wavelength range; when illuminated by a blue light source, its spectral reflectance curve is low across the entire wavelength range; when illuminated by an orange light source, its spectral reflectance curve is high in the long wavelength range; when illuminated by a green light source, its spectral reflectance curve is low across the entire wavelength range; when illuminated by a blue light source, its spectral reflectance curve is low across the entire wavelength range.

[0055] Therefore, based on spectral reflectance characteristics, single-wavelength light of multiple colors is used to collect reflectance change data for each band throughout the entire bacterial growth cycle, corresponding to the color changes of the sensor. The final interpretation is then based on the data from multiple bands, providing negative or positive results. This approach addresses the limitations of single-wavelength light source detection in adapting to a wide range of reflective substrates, as well as the limitations of single-wavelength reflectance data for algorithmic interpretation.

[0056] Example 1

[0057] like Figure 3 As shown, the microbial culture detection unit of this embodiment includes a cavity for placing a culture container 1, and an installation space 2 for installing a light signal acquisition component below the cavity. Specifically, the bottom of the culture container 1 is provided with a sensor 3 for sensing the sample state and changing color according to changes in the sample state. The light signal acquisition component includes a light source and a receiver 4. The light source is used to project at least two different colors of single-wavelength light onto the sensor 3, and the receiver 4 is used to receive the reflected light after being reflected by the sensor 3.

[0058] Specifically, a light source capable of emitting at least two different colors of single-wavelength light can be implemented in various ways. For example, the light source can be a single light source capable of directly emitting at least two different colors of single-wavelength light, such as a color-changing LED light source; the light source can also include a single light source capable of emitting white light, at least two filters capable of transmitting single-wavelength light of different colors, and a switching mechanism for controlling the sequential passing of the filters through the light source. Since white light contains all visible light bands, specific wavelengths of light can pass through the filters, thereby achieving the technical objective of emitting multiple specific colors of single-wavelength light; of course, the light source can also include at least two light-emitting units 5, each capable of emitting a single-wavelength light of a different color. In this embodiment, the light source also includes two light-emitting units 5, each capable of emitting a single-wavelength light of a different color. Of course, in some other preferred embodiments, the light source can be configured as a ring-shaped light source installed around the perimeter of the installation space 2, with at least two light-emitting units within the ring-shaped light source, each capable of emitting a single-wavelength light of a different color. The ring-shaped light source has the advantage of convenient installation and positioning.

[0059] Specifically, at least a portion of the inner surface of the mounting space 2 is a rough surface designed to eliminate stray light, thus preventing stray light from interfering with the detection results. The rough surface can take various structural forms, such as a serrated rough surface, a threaded rough surface, or a dotted raised rough surface. Furthermore, in general understanding, microbial culture instruments use strong signal detection; that is, the signal strength received by the receiver is sufficient for accurate analysis. Therefore, from the perspectives of performance, cost, and difficulty, the interference of stray light is usually not considered, nor is it necessary. In this embodiment, the focus is on the time for positive result interpretation, especially the sensitivity for interpreting weakly growing bacteria, which led to the consideration of reducing noise to improve sensitivity. In this embodiment, setting the inner surface of the mounting space as a rough surface to eliminate stray light helps improve sensitivity under specific conditions, especially by combining single-wavelength light of multiple colors, which greatly shortens the positive result reporting time for weakly growing bacteria.

[0060] In this embodiment, the mounting space 2 includes a first mounting area 2a located below the cavity, with the light source mounted on the side wall of the first mounting area 2a. By adjusting the tilt angle of the side wall of the first mounting area 2a, the light emitted by the light source mounted on the side wall of the first mounting area 2a can be easily projected onto the sensor 3, and the reflected light after being reflected by the sensor 3 can be received by the receiver 4. In this embodiment, the inner surface of the first mounting area 2a has an inner wall size that gradually decreases from top to bottom. Specifically, the inner surface of the first mounting area 2a can be a conical surface with an inner diameter that gradually decreases from top to bottom, or it can be a square pyramidal surface with an inner wall size that gradually decreases from top to bottom. Specifically, the receiver 4 can be mounted on the bottom surface of the first mounting area 2a; alternatively, a cylindrical mounting area 2b can be provided below the first mounting area 2a, and the receiver 4 can be mounted inside the cylindrical mounting area 2b.

[0061] This embodiment also proposes a microbial culture instrument, including an incubator, which is provided with at least one microbial culture and detection unit as described above in this embodiment.

[0062] Example 2

[0063] This embodiment of a blood culture detection system based on spectral reflectance technology includes a culture container, a sensor, a light signal acquisition component, and an interpretation module. Specifically, the culture container is used to culture the sample; the sensor senses the sample state and changes color according to changes in the sample state; the light signal acquisition component includes a light source and a receiver, the light source projects a single wavelength of light onto the sensor, and the receiver receives the reflected light signal after reflection from the sensor. The interpretation module determines whether the sample is infected based on the received reflected light signal. In this embodiment, the light source projects at least two different colors of single wavelength light onto the sensor.

[0064] Specifically, a light source capable of emitting at least two different colors of single-wavelength light can be implemented in various ways. For example, the light source can be a single light source capable of directly emitting at least two different colors of single-wavelength light, such as a color-changing LED light source; the light source can also include a single light source capable of emitting white light, at least two filters capable of transmitting single-wavelength light of different colors, and a switching mechanism for controlling the filters to pass sequentially through the light source. Since white light contains all visible light bands, specific wavelengths of light can pass through the filters, thereby achieving the technical objective of emitting multiple specific colors of single-wavelength light; of course, the light source can also include at least two light-emitting units, each capable of emitting single-wavelength light of a different color. In a preferred embodiment of this invention, the light source can be configured as a ring-shaped light source installed around the perimeter of the installation space, with at least two light-emitting units within the ring-shaped light source, each capable of emitting single-wavelength light of a different color. The ring-shaped light source has the advantage of convenient installation and positioning.

[0065] In some preferred embodiments, the single-wavelength light emitted by the light source can include short-wavelength light (such as blue light), long-wavelength light (such as red light), and single-wavelength light with wavelengths between short and long wavelengths (such as green light), etc. This allows the single-wavelength light of different colors emitted by the light source to cover a wider range of visible light wavelengths. Based on the principle of spectral reflectance, as the color of the sensor changes with the sample state, there will always be a single-wavelength light whose color and wavelength are close to or even equal to the color and wavelength of the reactor. Therefore, for this single-wavelength light, the sensor has a higher reflectivity, improving response sensitivity and thus increasing the accuracy of the positive rate reading. Tables 1-4 show the reflectivity data for single-wavelength light of different colors.

[0066] Table 1. Reflectance data for blue single-wavelength light

[0067]

[0068] Table 2 Reflectance data for green single-wavelength light

[0069]

[0070] Table 3. Reflectance data for orange single-wavelength light.

[0071]

[0072]

[0073] Table 4 Reflectance data for red single-wavelength light

[0074]

[0075] The data above shows that different colors of single-wavelength light have different response sensitivities to the same substrate film; for sensors in aerobic and anaerobic bottles, there is an optimal response spectrum corresponding to different color levels. During the transition from blue-violet to dark green, blue has the optimal response spectrum; during the transition from dark green to yellow, green has the optimal response spectrum. (This refers to different optimal response bands at different stages of the color change process of the sensing film).

[0076] Simultaneously, actual growth curves are collected, selecting only the data from the first 3 hours, as shown in Figure 4. From top to bottom, these represent green single-wavelength light, red single-wavelength light, and orange single-wavelength light. During interpretation in the module, the positive reporting time is first given using the curve with high response sensitivity to improve detection efficiency and ensure timely treatment for patients. Subsequently, the positive reporting results can be verified using curves of other colors of single-wavelength light to improve accuracy. In other words, multi-color single-wavelength light data can simultaneously meet the needs of timely positive reporting and accuracy, truly solving clinical pain points. Specifically, for weakly growing bacteria in clinical practice, the problems of long positive reporting times and misjudgments of positive and negative results can be effectively resolved.

[0077] In this embodiment, the interpretation module outputs a result determining whether a sample is infected based on whether the reflection signal parameter of any single wavelength light reaches a set threshold. If the reflection signal parameter of a single wavelength light reaches the set threshold, a preliminary positive interpretation result is obtained and displayed. If, during the sample culture period, the reflection signal parameters of all single wavelength lights do not reach the set threshold, a negative interpretation result is obtained and displayed. Thus, among multiple colors of single wavelength light, as long as the reflection signal parameter of any single wavelength light exceeds the set threshold, a preliminary positive interpretation result is obtained. This improves the sensitivity to weakly growing bacteria, avoids false negatives, and increases the accuracy of the positive rate interpretation. Specifically, the reflection signal parameter is a reflection signal parameter that can reflect changes in the sensor's color, including but not limited to at least one of the following: intensity of the reflection signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

[0078] Specifically, when the interpretation module obtains a preliminary positive interpretation result, it records and displays the preliminary positive interpretation time. The preliminary positive interpretation time is the time when the reflection signal parameter of the corresponding single wavelength light reaches the set threshold, or the preliminary positive interpretation time is the time when the interpretation module obtains the preliminary positive interpretation result based on the reflection signal parameter of the corresponding single wavelength light. The preliminary positive interpretation time provides a time reference for the verification program.

[0079] In this embodiment, the interpretation module is configured to: after obtaining a preliminary positive interpretation result, further determine whether to end or continue the detection based on the acquired reflected light signal. Specifically, in this embodiment, before continuing to acquire the light signal, it further includes: determining whether the culture container has been removed; if the culture container has been removed, the detection ends; if the culture container has not been removed, the reflected light signal continues to be acquired, and the interpretation module confirms whether to end or continue the detection based on the reflected light signal.

[0080] Specifically, in one embodiment of this example, during the continued detection process, if the interpretation module obtains a positive interpretation result based on the reflection signal parameters of other single wavelength light, it outputs and displays the positive interpretation result and ends the detection; if, until the end of the culture time, the interpretation module obtains a negative interpretation result based on the reflection signal parameters of other single wavelength light, the preliminary positive interpretation result is corrected to a negative interpretation result.

[0081] In another embodiment of this invention, after the interpretation module obtains and displays a preliminary positive interpretation result based on the reflection signal parameters of the corresponding single wavelength light, if the culture container has not been removed, the first verification procedure is initiated. In this embodiment, the set time period after the interpretation module obtains the preliminary positive interpretation result is designated as the first verification time period, which is the remaining culture time of the sample. During the first verification time period, the interpretation module verifies the preliminary positive interpretation result based on whether the reflection signal parameters of other single wavelength light reach a threshold. If the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single wavelength light, the preliminary positive interpretation result is eliminated. If the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of any other single wavelength light, a positive interpretation result is obtained and displayed, and the sample detection ends. In this way, the influence of false positive interpretations caused by environmental changes on the final interpretation result can be avoided.

[0082] Furthermore, if the wavelength distribution of the single-wavelength light projected by the optical signal acquisition component to the sensor is uneven, such as consisting of longer-wavelength red light and shorter-wavelength violet light, and the first wavelength light that yields the initial positive reading is red light, it indicates that the sensor is sensitive to red light and has high reflectivity, but may have lower reflectivity for violet light. In the first verification procedure, violet light may consistently produce negative readings due to its lower reflectivity, leading to false negatives. Therefore, to avoid false negatives in the first verification procedure caused by a large wavelength difference between other single-wavelength lights and the single-wavelength light that yields the initial positive reading, in a preferred embodiment of this example, the remaining culture time of the sample can be divided into a first verification period and a second verification period. If, during the first verification period, the verification module obtains negative readings based on the reflection signal parameters of all other single-wavelength lights, the second verification procedure is initiated while the sample continues to be verified. In the second verification procedure, the second verification period is defined as the second time interval following the first verification period. Within this second verification period, if a preliminary positive result is obtained again based on the reflection signal parameters of the single wavelength light from which the preliminary positive result was obtained (i.e., the same single wavelength light obtains at least two positive results), the interpretation module receives and displays the positive result, and the sample detection ends. Otherwise, the sample continues to be verified until the end of the second verification period. Specifically, the end of this second verification period is the end of the verification procedure. In particular, setting the second verification period after the first verification period allows it to be set to a sufficiently long time after the preliminary positive result. If the preliminary positive result is a false positive due to environmental changes, since the second verification period is sufficiently long after the preliminary positive result, the environmental change factor has been eliminated. Therefore, starting the second verification procedure within the second verification period can also avoid false positives caused by environmental changes.

[0083] This embodiment of the blood culture detection system based on spectral reflectance technology also includes a container placement module. Specifically, the container placement module includes a cavity for placing the culture container and an installation space for installing the optical signal acquisition component. The sensor is located at the bottom of the culture container and is used to sense the sample state and change color as the sample state changes.

[0084] This embodiment of the blood culture detection system based on spectral reflectance technology also includes a control module, which is used to control the light source to project different colors of single wavelength light onto the sensor in turn.

[0085] This embodiment of the blood culture detection system based on spectral reflectance technology also includes a display module, which displays the interpretation results and interpretation time. Specifically, the display module displays the preliminary positive interpretation result and its interpretation time at a second time; the first time is the interpretation time of the preliminary positive interpretation result, and the first time is equal to the second time. Thus, after obtaining the preliminary positive interpretation result, it can be displayed immediately through the display module. After obtaining the preliminary positive interpretation result information through the display module, medical personnel can immediately provide targeted treatment to the patient, ensuring timely treatment.

[0086] Of course, in some other embodiments, the interpretation module outputs a result determining whether the sample is infected based on whether the reflection signal parameters of all N single-wavelength lights reach a set threshold. Specifically, based on the color and wavelength distribution of the single-wavelength lights, it can also be: if the reflection signal parameters of N1 single-wavelength lights reach the set threshold, a preliminary positive interpretation result is obtained; if the culture container is not removed, the preliminary positive interpretation result is verified within a set verification time; within the verification time range, if the reflection signal parameters of another N2 single-wavelength lights reach the set threshold, a positive interpretation result is obtained; if the reflection signal parameters of another N3 single-wavelength lights do not reach the set threshold, a negative interpretation result is obtained; where: N1+N2≤N; N1+N3≤N; N1≤N3; N3>N / 2; Q≥N-N1-N2+1. That is, the preliminary positive interpretation result can be that the reflection signal parameters of one single-wavelength light reach the set threshold, or it can be that the reflection signal parameters of two or more single-wavelength lights reach the set threshold. In a more preferred embodiment, the colors or wavelengths of the two or more single-wavelength lights are relatively similar.

[0087] Example 3

[0088] like Figure 5 As shown in this embodiment, the alarm method of the blood culture detection system based on spectral reflectance technology includes the following steps:

[0089] S1: A light source sequentially projects N different colors of single-wavelength light onto a sensor located at the bottom of the culture container. When the light source projects the i-th single-wavelength light onto the sensor, a receiver receives the i-th reflected light signal after the i-th single-wavelength light is reflected by the sensor, obtaining the i-th reflected signal parameter; where N≥2. Specifically, the reflected signal parameter is a reflected signal parameter that can reflect changes in the sensor's color, including but not limited to at least one of the following: intensity of the reflected signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

[0090] S2: Determine whether the i-th reflected signal parameter has reached the set threshold: if yes, obtain and output the preliminary positive interpretation result, and execute S3; if no, execute S6. Specifically, the preliminary positive interpretation result can be output through the display module.

[0091] S3: Determine if the culture container has been removed: if yes, the detection ends; if no, start the verification program and execute S4.

[0092] S4: Use a light source to sequentially project N different colors of single wavelength light onto a sensor located at the bottom of the culture container; and when the light source projects the i-th single wavelength light onto the sensor, use a receiver to receive the i-th reflected light signal after the i-th single wavelength light is reflected by the sensor; where N≥2.

[0093] S5: Within the first verification time, determine whether the reflection signal parameter of any single wavelength light other than the i-th single wavelength light reaches the set threshold: if yes, a positive judgment result is obtained and the verification ends; if no, the preliminary positive judgment result is eliminated and S6 is executed.

[0094] In particular, in a preferred embodiment of this example, if the reflection signal parameters of all single-wavelength light except the i-th single-wavelength light do not reach the set threshold, then the second verification procedure is initiated: the second verification time period is the second verification time period set after the first verification time period. During the second verification time period, it is determined whether the i-th reflection signal parameter of the i-th single-wavelength light reaches the set threshold. If yes, a positive reading result is obtained and the verification ends; if no, then S6 is executed.

[0095] S6: Determine if the sample culture is complete: If yes, the test ends and a negative result is obtained and displayed; if no, proceed to S4.

[0096] Specifically, a light source capable of emitting at least two different colors of single-wavelength light can be implemented in various ways. For example, the light source can be a single light source capable of directly emitting at least two different colors of single-wavelength light, such as a color-changing LED light source; the light source can also include a single light source capable of emitting white light, at least two filters capable of transmitting single-wavelength light of different colors, and a switching mechanism for controlling the filters to pass sequentially through the light source. Since white light contains all visible light bands, specific wavelengths of light can pass through the filters, thereby achieving the technical objective of emitting multiple specific colors of single-wavelength light; of course, the light source can also include at least two light-emitting units, each capable of emitting single-wavelength light of a different color. In a preferred embodiment of this invention, the light source can be configured as a ring-shaped light source installed around the perimeter of the installation space, with at least two light-emitting units within the ring-shaped light source, each capable of emitting single-wavelength light of a different color. The ring-shaped light source has the advantage of convenient installation and positioning.

[0097] In some preferred embodiments, the single-wavelength light emitted by the light source can include short-wavelength light (such as blue light), long-wavelength light (such as red light), and single-wavelength light with wavelengths between short and long wavelengths (such as green light), etc. This allows the single-wavelength light of different colors emitted by the light source to cover a wider range of visible light wavelengths. Based on the principle of spectral reflection, as the color of the sensor changes with the sample state, there will always be a single-wavelength light whose color and wavelength are close to or even equal to the color and wavelength of the reactor. Therefore, for this single-wavelength light, the sensor has a higher reflectivity, improving response sensitivity and thus increasing the accuracy of the positive rate reading. (See Tables 1-4 and...) Figure 4 As shown.

[0098] Specifically, in this embodiment, the interpretation module outputs a result determining whether a sample is infected based on whether the reflection signal parameter of any single wavelength light reaches a set threshold: if the reflection signal parameter of a single wavelength light reaches the set threshold, a preliminary positive interpretation result is obtained and displayed; if, during the sample culture period, the reflection signal parameters of all single wavelength lights do not reach the set threshold, a negative interpretation result is obtained and displayed. Thus, among multiple colors of single wavelength light, as long as the reflection signal parameter of any single wavelength light exceeds the set threshold, a preliminary positive interpretation result is obtained, which can improve the response sensitivity to weakly growing bacteria, avoid false negatives, and improve the accuracy of the positive rate interpretation. Specifically, the reflection signal parameter is a reflection signal parameter that can reflect changes in the sensor's color, including but not limited to at least one of the following: intensity of the reflection signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

[0099] Specifically, when the interpretation module obtains a preliminary positive interpretation result, it records and displays the preliminary positive interpretation time. The preliminary positive interpretation time is the time when the reflection signal parameter of the corresponding single wavelength light reaches the set threshold, or the preliminary positive interpretation time is the time when the interpretation module obtains the preliminary positive interpretation result based on the reflection signal parameter of the corresponding single wavelength light. The preliminary positive interpretation time provides a time reference for the verification program.

[0100] In this embodiment, the interpretation module is configured to: after obtaining a preliminary positive interpretation result, further determine whether to end or continue the detection based on the acquired reflected light signal. Specifically, in this embodiment, before continuing to acquire the light signal, it further includes: determining whether the culture container has been removed; if the culture container has been removed, the detection ends; if the culture container has not been removed, the reflected light signal continues to be acquired, and the interpretation module confirms whether to end or continue the detection based on the reflected light signal.

[0101] Specifically, in one embodiment of this example, during the continued detection process, if the interpretation module obtains a positive interpretation result based on the reflection signal parameters of other single wavelength light, it outputs and displays the positive interpretation result and ends the detection; if, until the end of the culture time, the interpretation module obtains a negative interpretation result based on the reflection signal parameters of other single wavelength light, the preliminary positive interpretation result is corrected to a negative interpretation result.

[0102] In another embodiment of this invention, after the interpretation module obtains and displays a preliminary positive interpretation result based on the reflection signal parameters of the corresponding single wavelength light, if the culture container has not been removed, the first verification procedure is initiated. In this embodiment, the set time period after the interpretation module obtains the preliminary positive interpretation result is designated as the first verification time period. During the first verification time period, the interpretation module verifies the preliminary positive interpretation result based on whether the reflection signal parameters of other single wavelength light reach a threshold. If the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single wavelength light, the preliminary positive interpretation result is eliminated. If the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of any other single wavelength light, a positive interpretation result is obtained and displayed, and the sample detection ends. This avoids the impact of false positive interpretations caused by environmental changes on the final interpretation result.

[0103] Furthermore, if the wavelength distribution of the single-wavelength light projected by the optical signal acquisition component to the sensor is uneven, such as consisting of longer-wavelength red light and shorter-wavelength violet light, and the first wavelength light that yields the initial positive reading is red light, it indicates that the sensor is sensitive to red light and has high reflectivity, but may have lower reflectivity for violet light. In the first verification procedure, violet light may consistently result in a negative reading due to its lower reflectivity, leading to false negatives. Therefore, to avoid false negatives in the first verification procedure due to excessive wavelength differences between other single-wavelength lights and the single-wavelength light that yields the initial positive reading, in a preferred embodiment of this invention, if the reading module obtains a negative reading based on the reflection signal parameters of all other single-wavelength lights, the second verification procedure is initiated during the continued verification of the sample. In the second verification procedure, the second verification period is defined as the second set time period following the first verification time period. Within this second verification time period, if a preliminary positive result is obtained again based on the reflection signal parameters of the single wavelength light from which the preliminary positive result was obtained (i.e., the same single wavelength light obtains at least two positive results), the interpretation module obtains and displays the positive result, and the sample detection ends. Otherwise, the sample continues to be verified until the end of the second verification time period. Specifically, the end of the second verification time period is the end of the verification procedure. In particular, setting the second verification time period after the first verification time period allows it to be set to a sufficiently long period after the preliminary positive result. If the preliminary positive result is a false positive due to environmental changes, since the second verification time period is sufficiently long after the preliminary positive result, the environmental change factor has been eliminated. Therefore, starting the second verification procedure within the second verification time period can also avoid false positives caused by environmental changes.

[0104] The embodiments described above are merely preferred embodiments for fully illustrating the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A blood culture detection system based on spectral reflectance technology, characterized in that: include: Culture containers are used to culture samples; A sensor used to sense the state of a sample and change color as the state of the sample changes. An optical signal acquisition component is used to project a single wavelength of light onto the sensor and to receive the reflected light signal after it has been reflected by the sensor. The interpretation module is used to determine whether the sample is infected based on the received reflected light signal; The optical signal acquisition component is used to project at least two different colors of single wavelength light onto the sensor.

2. The blood culture detection system based on spectral reflectance technology according to claim 1, characterized in that: The interpretation module obtains the interpretation result of whether the sample is infected based on the reflection signal parameters of the single wavelength light.

3. The blood culture detection system based on spectral reflectance technology according to claim 1 or 2, characterized in that: The reflected signal parameters are reflected signal parameters that can reflect changes in the sensor color, including but not limited to at least one of the following: intensity of the reflected signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

4. The blood culture detection system based on spectral reflectance technology according to claim 1 or 2, characterized in that: The interpretation module outputs a result determining whether a sample is infected based on whether the reflection signal parameters of all N single-wavelength lights reach a set threshold: if the reflection signal parameters of N1 single-wavelength lights reach the set threshold, a preliminary positive interpretation result is obtained and displayed; within the verification time range, if the reflection signal parameters of another N2 single-wavelength lights reach the set threshold, a positive interpretation result is obtained and displayed; if the reflection signal parameters of another N3 single-wavelength lights do not reach the set threshold, a negative interpretation result is obtained; where: N1+N2≤N; N1+N3≤N; N1≤N3; N3>N / 2; Q≥N-N1-N2+1.

5. The blood culture detection system based on spectral reflectance technology according to claim 1 or 2, characterized in that: The interpretation module outputs a result to determine whether the sample is infected based on whether the reflection signal parameter of any single wavelength light reaches a set threshold: if the reflection signal parameter of a single wavelength light reaches the set threshold, a preliminary positive interpretation result is obtained and displayed; if the reflection signal parameters of all single wavelength lights do not reach the set threshold during the sample culture period, a negative interpretation result is obtained.

6. The blood culture detection system based on spectral reflectance technology according to claim 5, characterized in that: When the interpretation module obtains a preliminary positive interpretation result, it records and displays the time of the preliminary positive interpretation.

7. The blood culture detection system based on spectral reflectance technology according to claim 5 or 6, characterized in that: The interpretation module is configured to, after obtaining a preliminary positive interpretation result, further determine whether to end the detection or continue the detection based on the acquired reflected light signal.

8. The blood culture detection system based on spectral reflectance technology according to claim 7, characterized in that: During the continued detection process, if the interpretation module obtains a positive interpretation result based on the reflection signal parameters of other single wavelength light, it outputs and displays the positive interpretation result; if, until the end of the culture time, the interpretation module obtains a negative interpretation result based on the reflection signal parameters of other single wavelength light, it corrects the preliminary positive interpretation result to a negative interpretation result.

9. The blood culture detection system based on spectral reflectance technology according to claim 7, characterized in that: Before continuing to acquire light signals, the process also includes: determining whether the culture container has been removed; if the culture container has been removed, the detection ends; if the culture container has not been removed, the reflected light signal continues to be acquired, and the interpretation module confirms whether to end the detection or continue the detection based on the reflected light signal.

10. The blood culture detection system based on spectral reflectance technology according to claim 7, characterized in that: Once the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of the corresponding single wavelength light, it initiates the first verification procedure. The first verification period is defined as the first set time period after the interpretation module obtains the preliminary positive interpretation result. During the first verification period, the interpretation module verifies the preliminary positive interpretation result based on whether the reflection signal parameters of other single wavelength light reach the threshold. If the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single wavelength light, the preliminary positive interpretation result is eliminated. If the interpretation module obtains a preliminary positive interpretation result based on the reflection signal parameters of any other single wavelength light, then a positive interpretation result is obtained, and the verification ends.

11. The blood culture detection system based on spectral reflectance technology according to claim 10, characterized in that: If the interpretation module obtains a negative interpretation result based on the reflection signal parameters of all other single-wavelength light, a second verification procedure is initiated during the continued verification of the sample. The second verification period is defined as the second set time period after the first verification time period. During the second verification time period, if a preliminary positive interpretation result is obtained again based on the reflection signal parameters of the single-wavelength light from which the preliminary positive interpretation result was obtained, the interpretation module obtains a positive interpretation result, and the verification ends. Otherwise, the sample continues to be verified until the end of the second verification time period.

12. The blood culture detection system based on spectral reflectance technology according to any one of claims 1-11, characterized in that: The optical signal acquisition component includes a light source and a receiver. The light source is used to project a single wavelength of light onto the sensor, and the receiver is used to receive the reflected light signal after being reflected by the sensor. The light source is a single light source capable of emitting at least two different colors of single wavelength light; or, the light source includes a single light source capable of emitting white light and at least two filters capable of transmitting single wavelength light of different colors; or, the light source includes at least two light-emitting units, and different light-emitting units are capable of emitting single wavelength light of different colors. The light source is a ring-shaped light source installed in the installation space, and the ring-shaped light source is provided with at least two light-emitting units, each of which can emit a single wavelength of light of a different color.

13. The blood culture detection system based on spectral reflectance technology according to any one of claims 1-11, characterized in that: It also includes a container placement module, which includes a cavity for placing the culture container and an installation space for installing the optical signal acquisition component; the sensor is located at the bottom of the culture container.

14. An alarm method for a blood culture detection system based on spectral reflectance technology, characterized in that: Includes the following steps: S1: N different colors of single wavelength light are sequentially projected onto a sensor located at the bottom of the culture container using a light source. When the light source projects the i-th single wavelength light onto the sensor, the receiver receives the i-th reflected light signal after the i-th single wavelength light is reflected by the sensor. Where N≥2. S2: Determine whether the reflection signal parameters of the i-th reflected light signal have reached the set threshold: if yes, obtain and display the preliminary positive interpretation result, and execute S3; if no, execute S6. S3: Determine if the culture container has been removed: if yes, the detection ends; if no, start the verification program and execute S4. S4: Use a light source to sequentially project N different colors of single wavelength light onto a sensor located at the bottom of the culture container; and when the light source projects the i-th single wavelength light onto the sensor, use a receiver to receive the i-th reflected light signal after the i-th single wavelength light is reflected by the sensor; where N≥2; S5: Within the first verification time, determine whether the reflection signal parameter of any single wavelength light other than the i-th single wavelength light reaches the set threshold: if yes, obtain and display the positive judgment result and end the detection; if no, eliminate the preliminary positive judgment result and execute S6. S6: Determine if the sample culture is complete: If yes, the test ends and a negative result is obtained and displayed; if no, proceed to S4.

15. The alarm method for the blood culture detection system based on spectral reflectance technology according to claim 14, characterized in that: The reflected signal parameters are reflected signal parameters that can reflect changes in the sensor color, including but not limited to at least one of the following: intensity of the reflected signal, magnitude of reflectivity, difference in reflectivity changes, and rate of reflectivity change.

16. The alarm method for the blood culture detection system based on spectral reflectance technology according to claim 14 or 15, characterized in that: The light source is a single light source capable of emitting light of a single wavelength in at least two different colors; or, The light source includes a single light source capable of emitting white light and at least two filters capable of transmitting single wavelengths of light of different colors, wherein the filters are controlled to pass through the light source in turn; or, The light source includes at least two light-emitting units, each of which is capable of emitting a single wavelength of light of a different color.

Images