JPS5919303B2 - particle counting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a particle counting device that counts the number of platelets in blood while reducing the influence of contamination with other particles such as red blood cells and reducing counting errors.

Conventionally, in order to measure the number of platelets in blood using a particle counter, particles other than platelets in the blood, such as red blood cells and white blood cells, are separated as a pretreatment, only the platelets are taken out and diluted, and then the diluted solution is prepared. The particles are passed through the pores provided in the detector, and the electrical change that occurs when the particles pass through the pores, that is, the difference in electrical impedance caused by the dielectric constant or conductivity between the diluent and the particles, is detected and counted. was going there.

Therefore, with conventional particle counting devices, platelet separation operations such as centrifugation are required, and after measurement, it is necessary to convert the number of platelets to the original number per volume, and these operations and calculations require manual intervention. In other words, it was an obstacle to automation.
In addition, if the above separation operation is incorrectly performed, red blood cells and white blood cells larger than platelets may be mixed in, and these particles and platelets may be counted simultaneously, or a circuit may be installed to remove the signal due to particles larger than platelets. There are problems such as a significant decrease in the number of platelets, and errors in simultaneous passage with other particles. Furthermore, one of the error factors is that two or more platelets themselves enter the detection area at the same time, resulting in an error in mutual passage of platelets at the same time.
Furthermore, as a simultaneous passage correction circuit for correcting these simultaneous passage errors, conventional equipment adopted a method of adding an oscillator pulse signal based on the counting results, making the circuit complex and adjustment difficult. However, there was a problem that it was expensive.

The present invention provides a particle counting device that can perform simultaneous passage correction for particles other than platelets (erythrocytes and white blood cells) and platelets, and mutual simultaneous passage correction for platelets, and can perform particle counting with high accuracy. With the goal.

Furthermore, unlike the conventional method of adding a correction amount after counting pulses, the present invention is configured to perform simultaneous passage correction by simply changing the frequency division ratio, resulting in a simple circuit configuration and low cost. The purpose is to provide a particle counting device that is low cost.

Furthermore, the present invention eliminates the need for pretreatment such as centrifugation,
Another object of the present invention is to provide a particle counting device that does not require high-precision separation processing as in the past, even if necessary. Furthermore, since the present invention can automatically perform a series of simultaneous passage corrections for platelet counts, particle counting efficiency can be significantly improved when used in hospital laboratories that handle a large number of samples. The purpose is to provide equipment.

In order to achieve the above-mentioned object, the present invention provides a suction device that allows a blood dilution solution, which is a suspension of particles containing platelets, red blood cells, and white blood cells, to pass through a pore, a detector having the pore, and a detector having the pore. a detection device comprising a detection circuit that senses particles in the blood dilution liquid when they pass through the pores; a high gain amplification circuit that amplifies the output signal of the detection device to a sensitivity that allows platelet counting; a low-gain amplification circuit that amplifies the output signal of the detection device to a sensitivity that allows counting only red blood cells and white blood cells; a low-level comparison circuit that passes signals from platelets, red blood cells, and white blood cells from the output signal of the high-gain amplification circuit; a high-level comparison circuit that passes signals caused by red blood cells and white blood cells from the output signal of the gain amplification circuit; and an arithmetic circuit that subtracts the output signal of the high-level comparison circuit from the output signal of the low-level comparison circuit and passes the signal caused by platelets. a variable frequency divider circuit that divides the output of the arithmetic circuit with a variable frequency division ratio; a counting circuit that counts the output of the variable frequency divider circuit; and an auxiliary counting circuit that counts the output of the high level comparison circuit. , a frequency division ratio command circuit that outputs a signal for changing the frequency division ratio to the variable frequency division circuit according to the count value of the auxiliary counting circuit, and corrects the signal according to the count value of the counting circuit; It includes a display circuit that displays the counted value of the counting circuit, and changes the dividing ratio of the variable frequency dividing circuit according to the counted value of red blood cells and white blood cells, which are larger than platelets, and further divides the frequency according to the counted value of platelets. This is characterized in that the count value is corrected by changing the circumferential ratio.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, reference numeral 1 denotes a supple beaker containing a blood diluent 2 (i.e., a suspension of platelets, red blood cells, and white blood cell particles), and a detector 3 having a pore 3a is immersed in the supple beaker 1. The blood diluent 2 is sucked through the pores 3a by the suction device 4, and when the particles pass through the pores 3a, the detection circuit 5 senses and detects the particles. The device is configured.

In addition, in the above-mentioned detection device, when the particles pass through the pores 3a, the electrical changes caused by the difference in permittivity or conductivity between the diluent and the particles can be detected by, for example, providing electrodes inside and outside the detector 3. Particles are detected by converting impedance changes occurring in the pores 3a into electrical signals in the detection circuit 5. The detection circuit 5 is connected in parallel with a high gain amplification circuit 6 that amplifies the input signal to a sensitivity that allows counting of platelets, and a low gain amplification circuit 7 that amplifies the input signal to a sensitivity that allows only red blood cells and white blood cells to be counted. and the high gain amplifier circuit 6
A low level comparator circuit 8 is connected to pass signals from platelets, red blood cells and white blood cells, while a high level comparison circuit 9 is connected to the low gain amplifier circuit 7 to pass signals from red blood cells and white blood cells.

An arithmetic circuit 10 that passes the difference between the two input signals is connected to both comparison circuits 8 and 9 to form a subtraction circuit. A counting circuit 12 that counts the output of the variable frequency dividing circuit 11 is connected to the arithmetic circuit 10 via a variable frequency dividing circuit 11 that divides the input frequency with a variable frequency division ratio, and the counting circuit 12 has a count value. A display circuit 13 for displaying is connected. Further, an auxiliary counting circuit 14 that counts the output of the high level comparison circuit 9 is connected to the high level comparison circuit 9, and the auxiliary counting circuit 14 and the counting circuit 12 change the frequency division ratio according to the input value. A frequency division ratio command circuit 15 for commanding the frequency division ratio is connected as an input, and is connected as an output to the variable frequency division circuit 11. Next, to explain its effect, when particles containing platelets, red blood cells, and white blood cells in the blood diluent 2 pass through the pores 3a of the detector 3, there is an induction between the particles and the diluent. A difference occurs in the rate or conductivity, and the electrical change is sensed by the detection circuit 5 to detect particles. The output signal of this detection circuit 5 is sent to a high gain amplifier circuit 6 and a low gain amplifier circuit 7.
The former increases the sensitivity to platelets, while the latter increases the sensitivity to the point where only red blood cells and white blood cells can be counted. Furthermore, signals below a predetermined level are removed in each comparison circuit 8, 9, signals from platelets, red blood cells and white blood cells are passed through the low level comparison circuit 8, and signals from red blood cells and white blood cells are passed through the high level comparison circuit 9. , are sent to the arithmetic circuit 10, respectively. This arithmetic circuit 10 subtracts the output signal of the high level comparison circuit 9 (signals caused by red blood cells and white blood cells) from the output signal of the low level comparison circuit 8 (signals caused by platelets, red blood cells, and white blood cells), so only the signal caused by platelets passes. . This signal is counted by a counting circuit 12 via a variable frequency dividing circuit 11, and the counted value is displayed by a display circuit 13. However, according to the above-mentioned subtraction circuit, as shown in FIG. 2, when red blood cells are added to the platelet solution, the platelets that pass together with the red blood cells are also subtracted at the same time, causing an error in the simultaneous passage of red blood cells and platelets. As the number R increases from O to 1,000,000 and 2,000,000, the display value of the platelet count decreases. Furthermore, because platelets pass through each other at the same time, the displayed value of the platelet count decreases even when the red blood cell count R is O. In order to correct such simultaneous passage errors and approximate the ideal straight line L shown in FIG. 2, the auxiliary counting circuit 14 counts red blood cells and white blood cells and sends a signal to the division ratio command circuit 15, 1
When the count value of 4 reaches a predetermined value, a command is given to lower the frequency division ratio of the variable frequency divider circuit 11, and correction is performed by lowering the frequency division ratio one after another so that it approaches the straight line of R=O shown in FIG. be exposed. On the other hand, the output of the variable frequency dividing circuit 11 is counted by the counting circuit 12, but it needs to be corrected as the counted value increases, and feedback is sent to the dividing ratio command circuit 15 according to the counted value of the counting circuit 12. Then, the frequency division ratio is sequentially corrected so that the straight line R=O shown in FIG. 2 approaches the ideal straight line L. Now, as an example, what was a 50-decimal frequency division ratio at R-0 is
If the correction is made in the case shown in the figure, the result will be as follows.

When the frequency division ratio is sequentially switched as described above, the frequency is approximated by a broken line on the straight line of R-0, regardless of the concentration of red blood cells.

Note that the frequency division ratio is changed during counting measurement according to the count values of the auxiliary counting circuit 14 and the counting circuit 12. That is, as shown in the table above, for example, when the count value of the auxiliary counting circuit 14 is 5
The frequency division ratio is 50-decimal up to 00,000, but when it exceeds 500,000, the frequency division ratio is changed to 45-decimal based on a command from the frequency division ratio command circuit 15. Such corrections are continued in sequence until the measurement is completed. In addition, the mutual simultaneous passage correction of platelets is performed in the same manner, and the platelets almost lie on the ideal straight line L.

In the end, the count value corrected for simultaneous passage in this manner is finally displayed on the display circuit 13. In summary, the present invention provides two circuit systems, one for passing signals from red blood cells, white blood cells, and platelets, and the other for passing signals from only red blood cells and white blood cells. Based on the signal from the circuit, the signal from red blood cells and white blood cells is removed in real time, and only the signal from platelets is extracted.The auxiliary counting circuit is used to count the number of red blood cells and white blood cells, and as the count increases, the number of red blood cells and white blood cells increases. While correction for the decrease in platelets caused by the simultaneous passage of white blood cells and platelets is performed sequentially until the measurement is completed, a circuit is used to correct for simultaneous passage before the counting circuit for counting platelets. By providing a variable frequency dividing circuit and sequentially changing the frequency dividing ratio according to the value to be corrected, an effect is performed as if a correction pulse was added to the signal from platelets, and as a result,
This reduces the number of pulses caused by simultaneous passage of platelets.Furthermore, the error in the decrease in the count value caused by simultaneous passage of platelets correlates with the concentration of platelets in the sample, and as the concentration increases, the error increases, so the above-mentioned counting circuit The value to be corrected is sequentially changed according to the counted value, and the frequency division ratio is changed synergistically with the above-mentioned correction of simultaneous passage of red blood cells and white blood cells.

That is, the present invention reduces the platelet count due to simultaneous passage of red blood cells, white blood cells, and platelets, and simultaneous passage of platelets by sequentially changing the frequency division ratio of the variable frequency dividing circuit according to the correction values for both of the above. This allows a corrected and correct platelet count to be obtained at the end of the measurement.

Therefore, the present invention has the following excellent effects.

(a) It is possible to perform simultaneous passage correction for particles other than platelets (erythrocytes and white blood cells) and platelets, and simultaneous passage correction for platelets.

(b) Unlike the conventional method of adding a correction amount after counting pulses, the simultaneous passage correction is performed simply by changing the frequency division ratio, so the circuit configuration is simple and the cost is low.

(c) Pretreatment such as centrifugation is not required, and even if necessary, conventional high-precision separation treatment is not necessary.

(d) Since simultaneous passage correction of platelet counts can be performed automatically in a series, particle counting efficiency can be significantly improved when used in a hospital laboratory that handles a large number of samples.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, and FIG. 1 is an explanatory diagram of the program of a particle counting device, and FIG. 2 is a diagram showing the relationship between the true value of the platelet count and the counted value due to contamination with red blood cells. 1... Supplement beaker, 2... Blood diluent, 3... Detector, 3a... Pore, 4... Suction device , 5...detection circuit,
6...High gain amplifier circuit, 7...Low gain amplifier circuit, 8...Low level comparison circuit, 9...
...High level comparison circuit, 10... Arithmetic circuit,
11... Variable frequency divider circuit, 12... Counting circuit, 13... Display circuit, 14... Auxiliary counting circuit, 15... Division ratio command circuit.

Claims (1)

[Claims] 1. A suction device that allows a blood diluent, which is a suspension of particles containing platelets, red blood cells, and white blood cells, to pass through the pores, a detector having the pores, and when the particles in the blood diluent pass through the pores. a detection device consisting of a detection circuit that detects particles; a high gain amplification circuit that amplifies the output signal of the detection device to a sensitivity that allows counting of platelets; and a detection device that has a sensitivity that allows the output signal of the detection device to count only red blood cells and white blood cells. a low-gain amplification circuit for amplifying the output signal of the high-gain amplification circuit; a low-level comparison circuit for passing the signals caused by platelets, red blood cells, and white blood cells from the output signal of the high-gain amplification circuit; an arithmetic circuit that subtracts the output signal of the high level comparator circuit from an output signal of the low level comparator circuit to pass a signal from the platelets; and an arithmetic circuit that divides the output of the arithmetic circuit at a variable frequency division ratio. a counting circuit that counts the output of the variable frequency dividing circuit, an auxiliary counting circuit that counts the output of the high level comparison circuit, and a variable frequency dividing circuit that counts the output of the variable frequency dividing circuit; A frequency division ratio command circuit that outputs a signal for changing the frequency division ratio to a frequency circuit and corrects the signal according to the count value of the counting circuit, and a display circuit that displays the count value of the counting circuit. The count value is corrected by changing the frequency division ratio of the variable frequency dividing circuit according to the count value of red blood cells and white blood cells, which are larger than platelets, and further changing the frequency division ratio according to the count value of platelets. A particle counting device characterized by: