WO2007116892A1

WO2007116892A1 - Liquid drug infusion device

Info

Publication number: WO2007116892A1
Application number: PCT/JP2007/057496
Authority: WO
Inventors: Shigeru Nemoto
Original assignee: Nemoto Kyorindo Co., Ltd.
Priority date: 2006-04-06
Filing date: 2007-04-03
Publication date: 2007-10-18
Also published as: JP5005678B2; JPWO2007116892A1

Abstract

A liquid drug infusion device providing a minimum necessary level of CT value and also lightening the burden imposed on a subject. The liquid drug infusion device (100) with a syringe filled with a contrast agent is equipped with a piston drive mechanism (130) for operating the syringe and used together with a medical image diagnosis apparatus. The liquid drug infusion device (100) comprises data recording means (410) storing a coefficient table (411) in which coefficient a and coefficient b corresponding to each CT value are recorded in advance, weight input means (431) for receiving an input of the weight (x) of the subject, CT value input means (432) for receiving an input of a target CT value, calculating means (420) for referencing the coefficient table (411) and coefficients a, b corresponding to the inputted target CT value and determining an infusion speed (y) from expression (1) y = ax+b. Thus, the contrast agent is infused at the determined infusion speed (y).

Description

Chemical injection device

Technical field

TECHNICAL FIELD [0001] The present invention relates to a chemical solution injection device that injects a chemical solution into a subject, and particularly relates to a chemical solution injection device that injects a contrast medium and physiological saline as a chemical solution.

Background art

[0002] Currently, medical fluoroscopic imaging devices include X-ray CT (Computed Tomography) scanner, MRI (Magnetic Resonance Imaging) imaging, PET (Positron Emission Tomography) feeding, ultrasonic diagnostic equipment, angio equipment, CT Angio equipment, MRA (MR Angio) equipment, etc. are known.

[0003] When using the apparatus as described above, a contrast medium and physiological saline are injected into a subject for the purpose of obtaining a better fluoroscopic image. Since the contrast agent is a viscous liquid, a chemical injection device that automatically performs injection is put into practical use.

[0004] Usually, a contrast medium is injected at a constant injection speed, and imaging is started when the contrast level (CT f) suitable for imaging is reached. To reduce artifacts, saline is often injected after the contrast agent is injected. Patent Document 1 (Japanese Laid-Open Patent Publication No. 2004-113475) also describes an injection protocol in which the contrast agent injection rate is changed over time in order to obtain an optimal CT value. It is also described that even if the contrast agent is injected at the same injection speed and the same injection volume, the CT value varies depending on the body weight, so that it changes depending on the body weight.

[0005] However, the optimal contrast agent injection rate for all examination sites or for all purposes has not been clearly known. The injection rate is often determined empirically, and when the CT value exceeds a predetermined level, CT imaging is started. For this reason, the CT value level may be increased more than necessary, and the contrast medium is wasted and the subject is burdened.

Patent Document 1: JP 2004-113475 A

Disclosure of the invention Problems to be solved by the invention

[0006] In view of such circumstances, an object of the present invention is to provide a chemical solution injection device that reduces the burden on a subject by reducing the CT value to a necessary level.

Means for solving the problem

[0007] The present invention relates to the following matters.

[0008] 1. In an injection device that is equipped with a syringe filled with a contrast medium, includes a piston drive mechanism that operates the syringe, and is used together with a medical image diagnostic apparatus.

Data recording means for storing a coefficient table in which coefficient a and coefficient b are recorded in advance corresponding to a plurality of CT values;

A body weight input means for receiving an input of the subject's weight (X);

CT value input means for receiving input of the target CT value;

Refer to the coefficient table, refer to the coefficient a and coefficient b corresponding to the input target CT value, and formula (1)

y = ax + b

According to the calculation means for obtaining the injection rate (y)

Have

An injection apparatus characterized by injecting a contrast medium in accordance with a determined injection speed (y).

[0009] 2. The injection apparatus according to 1 above, further comprising contrast medium information input means for receiving input of contrast medium information related to a dose amount.

[0010] 3. Scan time input means for receiving an input of a scheduled imaging time (T) by the medical image diagnostic apparatus;

Correction time input means for accepting input of correction time (a) and

Further comprising

The calculation means further includes the equation (2)

z = (T + a) Xy

And has a function to calculate the contrast medium injection amount (z),

3. The injection apparatus according to 1 or 2 above, wherein the contrast medium is injected according to the determined injection speed (y) and contrast medium injection amount (z). [0011] 4. Input target CT value force CT value force that exists in the coefficient table when it does not exist in the coefficient table. 4. The injection device according to any one of 3.

[0012] 5. The data recording means is an experimental data which records a CT value actually measured by the medical diagnostic imaging apparatus after injection of a contrast medium, an injection speed (y) and a weight (X) performed. A data table, and accepting additional records in the experimental data table as new records of injection speed (y) and body weight (X) in the column corresponding to the CT value actually measured in the latest measurement,

The computing means has a function of recalculating the coefficient a and the coefficient b corresponding to each CT value by statistical calculation based on the formula (1) with reference to the experimental data table after additional recording. In addition,

The coefficient table receives the coefficient a and the coefficient b recalculated by the calculation means, and has a correction function that replaces the existing coefficient a and coefficient b with the recalculated coefficient a and coefficient b! / 5. The injection device according to any one of 1 to 4 above.

[0013] 6. The injection device according to any one of 1 to 5 above, which is used for CT imaging of the heart or aorta.

The invention's effect

[0014] According to the present invention, it is possible to provide a drug solution injection device that reduces the degree of contrast (CT value) to a necessary level, eliminates waste of the contrast agent, and reduces the burden on the subject.

In particular, according to the present invention, it is possible to provide an injection device that is optimal for contrast examinations (X-ray CT angio, X-ray angio) of the heart, aorta, and the like.

Brief Description of Drawings

FIG. 1 is a diagram showing an example of an injection device according to the present invention.

FIG. 2 is a perspective view showing an appearance of an example of an injection device.

FIG. 3 is a block diagram for explaining the interrelationship of each means of the injection device.

FIG. 4 is a flowchart for explaining processing steps in the injection apparatus of the present invention.

FIG. 5 is a diagram showing a coefficient table.

FIG. 6 is a graph illustrating an example of how to obtain coefficient a and coefficient b. FIG. 7 is a scatter diagram showing inspection data.

FIG. 8 is a diagram showing a specific example of a coefficient table.

100 infusion device

101 Injection control unit

102 cable

103 Main operation panel

104 Display

107 Hands-up

108 cable

110 injection head

111 Stand

112 arms

113 Head body

114 recess

130 Piston drive mechanism

200C, 200P syringe

210 cylinders

220 piston

230 Connecting tube

410 Data recording means

411 coefficient table

412 Experimental data table

420 Calculation means

431 Weight input means

432 CT value input means

433 Scan time input means

434 Correction time input means 437 Contrast information input means

BEST MODE FOR CARRYING OUT THE INVENTION

[0018] One embodiment of the present invention will be described below with reference to the drawings. The medical diagnostic imaging system in which the injection device is used includes the injection device 100 and an X-ray CT angiography device (not shown) which is a medical diagnostic imaging device, and preferably includes the injection device 100 and the CT angiography device. Is wired or wirelessly connected.

As shown in FIG. 1, for example, the injection device 100 includes an injection head 110 mounted on an upper part of an arm 112 connected to a stand 111, and a separate injection control unit 101 connected to a cable 102 by a cable 102. It is connected. The injection control unit 101 includes a main operation panel 103, a display unit 104, a node unit 107 connected by a cable 108, and the like.

As shown in FIG. 2, the injection head 110 has two concave portions 114 formed on the upper surface of the head body 113 as a syringe holding mechanism, and the two syringes 200C and 200P are formed in the concave portion 114. Installed. The syringes 200C and P have a cylinder 210 and a piston 220. The syringe 200C is filled with a contrast medium for angio, and the syringe 200P is filled with physiological saline as a diluent. The tips of the two syringes attached to the head body 113 are connected by a connecting tube 230. In addition, the piston 220 of each syringe is pushed by the piston drive mechanism 130 that can be moved independently, so that contrast medium injection, physiological saline injection, and simultaneous injection of both can be performed. This figure shows a double-head type injection device that can be equipped with two syringes. If only the injection of contrast medium is required, a single-head type with only one syringe can be used!

[0021] Here, as the general configuration of the piston drive mechanism, the control mechanism, and the like, a known configuration can be adopted.

FIG. 3 is a block diagram showing the relationship between the components of the present invention. The data recording means 410 preferably exists as a part of the function of the injection control unit 101, and is composed of hardware such as a hard disk, a CD-R, a flexible disk, and RAM, and software for operating the hardware. The data recording means 410 logically has a coefficient table 411 and preferably an experimental data table 412.

[0023] The computing means 420 is a part of the main functions of the injection control unit 101, and the CPU and R It is composed of AM, ROM, etc., and access to the data recording means 410 is possible.

[0024] Weight input means 431, CT value input means 432, scan time input means 433, preferably correction time input means 434, and contrast agent information input means 437 are provided, which are preferably main operation panel 103. It is provided as part of the function. Further, the contrast medium information input means 437 may be capable of communicating with, for example, an IC chip attached or embedded in a syringe. In that case, manual input can be omitted. In addition, personal information such as weight may be transmitted from the hospital management server via a hospital LAN or the like, and the weight input means may be such a communication system.

[0025] FIG. 4 shows steps until injection is performed according to the embodiment of the present invention. First, in steps S1 to S3, the target CT value, the contrast medium information including the concentration information of the odor amount, and the body weight (X) of the subject are respectively converted into the CT value input means 432, the contrast medium information input means 43, and the body weight input means. Input from 431. These may also be input as a force keyboard input by touching and selecting on the screen of the main operation panel 103 which is preferably a touch panel. In steps S4 and S5, the scheduled photographing time (T) and the correction time (α) are input from the scan time input means 433 and the correction time input means 434, respectively. This is also preferably entered by touching and selecting on the screen of the main operation panel 103, which is a touch panel.

In response to the input, in step S 6, the calculation means 420 refers to the coefficient table 411 in the data recording means 410. An example of the coefficient table 411 is shown in FIG. Referring to this table, coefficient a and coefficient b are given according to the contrast agent type and target CT value. For example, using a 320 od formulation and targeting a CT value of 400 HU, the values a (320,400) and b (320,400) are obtained as the coefficient a and the coefficient b.

[0027] Next, in step S7, the injection rate (y) is

Formula 1J y = ax + b

According to the calculation.

[0028] Then, in step 8, the calculation means 420 calculates the injection amount (ζ) from y, the scheduled imaging time (T) and the correction time (α) separately input,

Formula (2) z = (T + a) Xy Ask for.

Here, T + a is an injection time. Therefore, calculation according to equation (2) is not essential. If T + a reveals the injection time, then injection is feasible.

[0030] The calculated injection rate, injection amount, injection time, and input data are preferably displayed on the display unit 104 of the injection device 100. The operator confirms these values as necessary, and when a start command is input, the injection of contrast medium starts.

[0031] When the target CT value does not exist in the coefficient table, the CT value existing in the table is larger and smaller than the target CT, closest to the one, and the coefficient a corresponding to the CT value. For example, the coefficient may be interpolated by proportional distribution. For example, if the target CT value is set to 320HU for the 300 oz product from the coefficient table in Figure 5, the coefficient a is

{a (300,350) -a (300,300)} X 2/5 + a (300,300)

Can be obtained. The same applies to the coefficient b.

Next, creation of a coefficient table will be described. The coefficient a and the coefficient b are basically determined by a large number of clinical outcomes empirically. In one experimental method, first, the type of contrast medium is determined, and X-ray CT angiography is performed on a large number of subjects at different injection rates. For example, as shown in FIG. 6, it is assumed that curve A and curve B are obtained for two injections with different body weight (x) or infusion rate (y). Suppose that the shooting time is T

W

Curve A and Curve B as CT values (CT) that can secure the imaging window at time T

W TW

In contrast, CT and CT are obtained. A number of such clinical experiments were conducted and the same C

TW-A TW-B

Collect the injection conditions that give T (e.g. CT value 300) and calculate the weight (X) and injection rate (y) respectively.

TW

This can be plotted as a horizontal axis and a vertical axis, and a straight line y = ax + b can be obtained from the scatter plot by the method of least squares to obtain coefficient a and coefficient b. This is CT, 400, 350, 300

TW

And 250HU, the corresponding coefficient a and coefficient b can be obtained. This calculation method is based on the idea that the CT value giving the radiographing window is the target CT value, but the maximum CT value or the maximum force of the CT value is set to 10%. The present invention can be applied to.

[0033] Further, a is a parameter that is appropriately added by a doctor depending on individual differences between subjects and imaging time. Typically chosen between 7 and: LO seconds. Also, set the injection time considering α. I also prefer to do the above experiment.

[0034] Fig. 7 shows an example of inspection results. Each data approximates a straight line relatively well. From the least squares method,

Achieved For CT value 400:

y = 0. 022x + l. 0439 (r ² = 0. 4901),

Achieved CT value 350:

y = 0. 0184x + l. 1176 (r ² = 0. 7068),

Achieved For CT value 300:

y = 0. 0158x + l. 2919 (r ² = 0. 8644)

Respectively.

As a result, FIG. 8 is obtained as a coefficient table. If the subject is 65 kg, from equation (1)

400HU: 2. 47mlZ seconds

350HU: 2.32mlZ seconds

300HU: 2. 31mlZ seconds

Thus, the injection rate for obtaining the target CT value is determined. Furthermore, if the imaging time is 30 seconds, for example, the correction time of 8 seconds is added, and the injection time is 38 seconds, for example. Also, the amount of force injection can be obtained from equation (2).

[0036] When injection was performed with the injection device as described above, almost the target CT value was obtained in many examinations.

[0037] In addition, the apparatus of the present invention includes the CT value actually measured by the examination, the infusion rate (y) performed, and the body weight, including the examination data used when the coefficient a and the coefficient b were first obtained. More preferably, (X) is stored in an experimental data table. Then, the newly measured data is updated and saved as a record, and the above statistical calculation is performed again based on the experimental data table to which the new data is added. And the coefficient b is obtained.

[0038] Note that it is also preferable to have means for displaying a scatter diagram as shown in Fig. 7, and at that time, it is also preferable to have a function of deleting abnormal points that deviate greatly from a straight line. As a result, more general As the coefficient a and coefficient b are obtained and the test examples are accumulated, the general accuracy gradually increases.

[0039] The approximation by equation (1) as described above is particularly effective for cardiac and aortic angio tests and CT angio tests using contrast agents. Examples of the aortic examination site include the aortic arch, thoracic aorta, subpulmonary artery, and subdiaphragmatic artery.

[0040] In the above description, the "means" constituting the system of the present invention may be a dedicated mechanism, may also serve as other means, or may be logical on a computer system. It may be a configuration. Those specific configurations can be easily configured by those skilled in the art by referring to the present specification.

Claims

The scope of the claims

[1] In an injection device that is equipped with a syringe filled with a contrast agent and includes a piston drive mechanism that operates the syringe, and that is used with a medical diagnostic imaging device.

A body weight input means for receiving an input of the subject's weight (X);

CT value input means for receiving input of the target CT value;

y = ax + b

According to the calculation means for obtaining the injection rate (y)

Have

2. The injection device according to claim 1, further comprising contrast medium information input means for receiving input of contrast medium information related to the amount of throat.

[3] Scan time input means for receiving an input of a scheduled photographing time (T) by the medical image diagnostic apparatus;

Correction time input means for accepting input of correction time (a) and

Further comprising

The calculation means further includes the equation (2)

z = (T + a) Xy

And has a function to calculate the contrast medium injection amount (z),

3. The injection apparatus according to claim 1, wherein the contrast medium is injected according to the determined injection speed (y) and the contrast medium injection amount (z).

[4] The method further comprises an interpolation means for interpolating the CT value force existing in the coefficient table to obtain the coefficient a and the coefficient b when the inputted target CT value does not exist in the coefficient table. 4. The injection device according to any one of 3.

[5] The data recording means is injected with a contrast agent and measured by the medical image diagnostic apparatus. In addition, there is an experimental data table in which recorded CT values, infusion rates performed (y) and body weights (X) are recorded, and the infusion rates in the column corresponding to the CT values actually measured in the latest measurement ( (y) and weight (X) as new records, and accept additional records in the experiment data table,

The coefficient table receives the coefficient a and the coefficient b recalculated by the calculation means, and has a correction function that replaces the existing coefficient a and coefficient b with the recalculated coefficient a and coefficient b! / The injection device according to any one of claims 1 to 4.

The injection device according to any one of claims 1 to 5, which is used for CT imaging of a heart or an aorta.