WO2009123256A1

WO2009123256A1 - Medical solution injection device

Info

Publication number: WO2009123256A1
Application number: PCT/JP2009/056795
Authority: WO
Inventors: 茂根本
Original assignee: 株式会社根本杏林堂
Priority date: 2008-04-02
Filing date: 2009-04-01
Publication date: 2009-10-08
Also published as: JPWO2009123256A1; JP2014014715A; JP5394371B2; JP6000926B2

Abstract

A medical solution injection device (100) is provided with an injection head (110) on which a syringe filled with a contrast agent is mounted and an injection control unit (101) including a control section (141) that controls an operation of the injection head (101). The injection control unit (110) comprises an actual injection amount operation section (146) for calculating a contrast agent injection amount for an actual injection so that the maximum CT value obtained in the actual injection becomes a predetermined value in accordance with the maximum CT value obtained by a CT device (300) in a test injection. The control section (141) controls the injection head (110), at the actual injection, so as to inject the contrast agent of the amount calculated by the actual injection amount operation unit (146).

Description

Chemical injection device

The present invention relates to a chemical injection device used for injecting a contrast medium into a subject in order to take a CT image of the subject.

Medical diagnostic imaging apparatuses include a CT (Computed Tomography) scanner, an MRI (Magnetic Resonance Imaging) apparatus, a PET (Positron Emission Tomography) apparatus, an angiographic apparatus, and an MRA (MR Angio) apparatus. When taking a CT image of a subject using these devices, a chemical solution such as a contrast medium or physiological saline is often injected into the subject.

It is common to automatically inject a chemical solution into a subject using a chemical solution injection device. The chemical solution injector includes an injection head to which a syringe filled with a chemical solution is detachably mounted, and an injection control unit that controls the operation of the injection head. The syringe has a cylinder and a piston inserted in the cylinder so as to be movable in the axial direction, and the liquid medicine is filled in the cylinder. The injection head includes a piston drive mechanism for pushing the piston of the syringe attached to the injection head into the cylinder. An injection needle is connected to the tip of the cylinder via an extension tube, and after the injection needle is punctured into the blood vessel to be examined, the piston drive mechanism pushes the piston into the cylinder to inject the drug solution in the cylinder into the subject. be able to.

In CT imaging using a contrast agent, the injection amount of the contrast agent is set so as to obtain a good contrast effect. Moreover, it is desirable to perform CT image capturing at the timing when the contrast agent that has flowed on the bloodstream of the subject reaches the imaging region after the injection of the contrast agent. Therefore, in the conventional diagnostic imaging apparatus, in order to measure the arrival time of the contrast agent at the imaging site, a monitoring scan of the imaging site may be performed prior to the main scan. For the measurement of the arrival time of the contrast medium at the imaging site, a CT value proportional to the concentration of the contrast medium in the blood is used. For example, in Patent Document 1, after injecting a contrast medium into a subject, a monitoring scan is performed to calculate a CT value at an imaging region, and a predetermined condition is satisfied, for example, when the CT value exceeds a preset threshold value. In such a case, a CT apparatus that executes a main scan is disclosed.

JP 2007-111255 A

Generally, the contrast effect is highly related to the weight of the subject, and the amount of contrast medium injected is often set according to the weight of the subject. In that case, the same amount of contrast agent is injected into a subject having the same weight. However, in reality, there are individual differences such as circulating blood volume, cardiac output, and vascular resistance, so even if the same amount of contrast medium is injected, the CT value varies widely between subjects and is stable between subjects. It was generally difficult to obtain a contrast effect. It is possible to stabilize the contrast effect by setting the injection volume of the contrast medium in consideration of these circulating blood volume, etc. However, for that purpose, it is necessary to measure the circulating blood volume, etc., and determine the contrast medium injection volume The process to do so becomes complicated.

An object of the present invention is to provide a chemical injection device that can easily set the injection amount of a contrast medium according to individual differences in a chemical injection device that injects a contrast medium in order to take a CT image with the CT apparatus. .

In order to achieve the above object, the chemical injection device of the present invention is equipped with a syringe filled with a contrast agent that changes the CT value of the subject by injection in order to capture a CT image of the subject with the CT device. In a drug solution injection device comprising an injection head for injecting a contrast medium by operating a syringe, and a control unit for controlling the injection head to perform a test injection prior to the main injection,
Based on the maximum CT value obtained by the CT injection by the test injection, the injection amount calculation unit for main injection for calculating the contrast agent injection amount in the main injection so that the maximum CT value obtained by the main injection becomes a predetermined value. Have
The control unit controls the injection head so that the amount of contrast medium calculated by the injection amount calculation unit for main injection is injected during the main injection.

In the chemical injection device of the present invention, the injection amount calculation unit for main injection is I _a = I _t × (C _a −C ₀ ) / (C _t −C ₀ ) (where I _a is the contrast in the main injection) injection amount of the agent, the injection amount of the contrast medium in I _t is the test injection, target maximum CT value C _a to be obtained by the CT apparatus in the present injection, C _t is the CT apparatus in the test injection The obtained maximum CT value, C ₀ is the CT value before contrast agent injection.) The injection amount of the contrast agent in the main injection can be calculated. In this case, the injection protocol of the test injection and the main injection can be an injection protocol in which the contrast medium is injected at a constant injection rate during a predetermined injection time.

In addition, the chemical injection device of the present invention further includes an interface that enables data transmission / reception to / from the CT device, and receives the maximum CT value obtained by the test injection through this interface. Also good. In a preferred aspect of the present invention, the apparatus further includes a test injection injection amount calculation unit that calculates the injection amount of the contrast agent at the time of the test injection based on at least a part of the body factor of the subject and the chemical solution factor of the contrast agent. The control unit is further configured to correct the time from the injection start of the contrast agent to the maximum CT value measured by the CT apparatus by the test injection from the injection amount calculated by the main injection amount calculation unit. May be.

According to the present invention, the contrast agent injection amount in the main injection is calculated using the maximum CT value obtained by the CT apparatus by the test injection, and the main injection is executed with the calculated injection amount. The amount of contrast medium injected according to individual differences can be set very easily.

It is a perspective view of an example of CT system to which the present invention is applied. It is a perspective view of the chemical injection device shown in FIG. It is a perspective view which shows the injection | pouring head shown in FIG. 2 with the syringe with which it is mounted | worn. It is the block diagram which represented the CT system shown in FIG. 1 by the function. It is a figure which shows an example of the setting screen for test injection | pouring. It is a figure which shows an example of the setting screen for this injection | pouring implemented after test injection | pouring. It is a figure which shows an example of the screen for imaging timing confirmation in this injection | pouring.

Referring to FIG. 1, a CT system 1000 according to an embodiment of the present invention is shown that includes a chemical injection device 100 and a CT device 300 that is a fluoroscopic imaging device. The CT apparatus 300 and the chemical injection device 100 are connected to each other so that data relating to the chemical injection in the chemical injection apparatus 100 can be transmitted to the CT apparatus 300.

The CT apparatus 300 includes a scanner 301 that performs an imaging operation, and an imaging control unit 302 that controls the operation of the scanner 301. In FIG. 1, all the components of the CT system 1000 are shown to be arranged in the same room. However, when actually capturing a CT image of a subject, the imaging control unit 302 includes a scanner 301 and a chemical solution. It is arranged in a separate chamber from the injection device 100.

For example, as shown in FIG. 2, the chemical injection device 100 includes an injection head 110 that is mounted on an upper portion of a stand 111 via an arm 112, and an injection control unit 101 that is connected to the injection head 110 with a cable 102. ing. The injection control unit 101 includes a main operation panel 103, a touch panel 104 serving as a display unit and an input unit, a hand unit 107 serving as an auxiliary input unit connected to the main body of the injection control unit 101 with a cable 108, and the like. ing.

As shown in FIG. 3, the injection head 110 has two concave portions 114 formed as syringe holding portions on the upper surface of the head main body 113, and syringes 200 C and 200 P are detachably attached to the concave portions 114, respectively. The syringes 200 C and 200 P have a cylinder 210 and a piston 220. Each of the syringes 200C and 200P is filled with a chemical solution. For example, one syringe 200C is filled with a contrast agent that can change the CT value of the subject by injection, and the other syringe 200P is filled with physiological saline. Can be filled. Connected to the distal ends of the two syringes 200C and 200P attached to the head main body 113 is a connecting tube 230 that merges into one at the middle and is provided with an injection needle at the distal end.

The injection head 110 is provided with two piston drive mechanisms 130 that are driven independently of each other to operate the pistons 220 of the syringes 200 C and 200 P mounted in the recesses 114, corresponding to the recesses 114. . These piston driving mechanisms 130 operate the pistons 220 of the syringes 200C and 200P respectively attached to the recesses 114, thereby separately or simultaneously applying the contrast medium and the physiological saline filled in the syringes 200C and 200P to the subject. Can be injected.

As the mechanism for holding the syringes 200C and 200P of the injection head 110 in the head main body 113 and the piston drive mechanism 130, a known mechanism generally used for this type of injection device can be adopted.

FIG. 4 is a block diagram functionally showing the CT system 1000 of this embodiment. Each block shown in FIG. 4 exists as at least a part of the configuration described in FIGS. 1 to 3 or a combination of at least a part thereof, and may be configured as hardware or as a logic circuit. It may be configured.

As shown in FIG. 4, the injection control unit 101 includes a control unit 141, an input unit 142, a display unit 143, a test injection injection amount calculation unit 145, a main injection injection amount calculation unit 146, and an interface (I / F). 147.

The chemical solution injection device 100 has two injection modes of test injection and main injection as injection modes of the chemical solution. The main injection is an injection of a contrast medium for imaging a CT image of a subject for diagnostic purposes. The test injection measures the time from the injection of the contrast medium to the target imaging site. For injection of contrast medium. The test injection is performed prior to the main injection, and a smaller amount of contrast agent is injected in the test injection than in the main injection.

The input unit 142 corresponds to the main operation panel 103 and the touch panel 104 shown in FIG. 2, and includes various settings of the chemical injection device 100 by the operator and the maximum CT value obtained from the CT device 300 by the test injection. Accepts input of data necessary for determination of chemical injection conditions. The display unit 143 corresponds to the touch panel 104 shown in FIG. 2, and displays a setting screen, a data input screen, a screen representing an operation state, and the like of the chemical liquid injector 100. As described above, in this embodiment, the touch panel 104 has both the function as a part of the input unit 142 and the function of the display unit.

The test injection injection amount calculation unit 145 calculates the contrast agent injection amount at the time of test injection based on the data input from the input unit 142, and the main injection injection amount calculation unit 145 is input from the input unit 142. Further, based on the maximum CT value obtained by the test injection, the amount of contrast medium injected at the time of the main injection is calculated. The control unit 141 controls each part of the injection control unit 101 and the injection head 110 so that the overall operation of the chemical solution injection apparatus 100 including the test injection and the main injection is operated according to a sequence including an operation procedure described later.

The control unit 141 is connected to the CT apparatus 300 via the interface 147, and transmits a contrast medium injection start signal to the CT apparatus 300 simultaneously with the start of the test injection and the start of the main injection, respectively. .

The input unit 142 and the display unit 143 can be provided not only in the injection control unit 101 but also in the injection head 110. In this embodiment, the injection head 110 includes a plurality of operation buttons 116 as a part of the input unit 142 and a display panel 115 as a part of the display unit 143. The operation buttons 116 and the display panel 115 can be used for inputting and displaying data necessary for test injection, for example.

Next, the operation of the above-described chemical injection device 100 will be described.

First, the operator attaches the syringe 200C filled with the contrast medium and the syringe 200P filled with physiological saline to the predetermined recesses 114 of the injection head 110, respectively, and turns on the power of the drug solution injection device 100. When the power of the chemical liquid injector 100 is turned on, the controller 141 advances each piston drive mechanism 130 at the most retracted position. Thereby, the piston drive mechanism 130 holds the end of the piston 220 of the syringes 200 C and 200 P in the piston drive mechanism 130. Each syringe 200C, 200P is connected to an injection needle through an extension tube 230, and this injection needle is punctured by a subject.

Next, the control unit 141 causes the display unit 143 to display a setting screen for test injection. Here, a case where the display unit 143 is a touch panel and also serves as the input unit 142 will be described as an example. Therefore, in the following description, the display unit 143 and the input unit 142 may be referred to as a touch panel.

FIG. 5 shows an example of a test injection setting screen displayed on the display unit 143. On the setting screen 150 shown in FIG. 5, a body group selection button group 151, an imaging region selection button group 152, a weight input field 153, and a test injection start button 154 are displayed.

The body classification selection button group 151 includes four buttons that divide an image simulating a subject who is supine into a head, a chest, a waist, and a leg, and an operator selects and touches one of these buttons. By doing so, the classification corresponding to the touched button is input. The selected button is highlighted. FIG. 5 shows a state where the chest is selected.

The imaging region selection button group 152 has one or more buttons that specifically indicate the imaging region from the selected body segment that is displayed when the body segment is input. When the operator selects and touches a button representing a target imaging region, an imaging region corresponding to the touched region is input. FIG. 5 shows a state where the heart is selected as the imaging region.

The body weight input field 153 is a field for inputting the subject's body weight numerically, and is ready for input after inputting the imaging region. When the body weight of the subject is input, the control unit 141 transmits the input weight data to the test injection amount calculation unit 145, and the test injection amount calculation unit 145 that has received the data is given in advance. An injection amount corresponding to the weight of the subject is calculated from the weight data according to the calculation formula. It is preferable that the amount of contrast medium injected at the time of test injection is as small as possible within a range where a contrast effect can be obtained so that the burden on the subject due to the test injection is reduced. The calculation formula of the contrast agent injection amount can be given by, for example, an expression obtained by multiplying the body weight by a predetermined coefficient, and this coefficient may be changed by the operator as necessary.

Here, an example is shown in which the contrast medium injection amount at the time of test injection is obtained from the body weight of the subject, but in addition, at least a part of the liquid factor such as the body factor such as the subject's age, height, and sex, and the type of liquid medicine The amount of contrast medium injected at the time of test injection can be determined in consideration of the above. In this way, by calculating the contrast agent injection amount at the time of test injection based on at least a part of the body factor and chemical solution factor, the contrast agent injection amount at the test injection can be adjusted according to the subject and the type of chemical solution Can do. This enables a test injection with a smaller contrast medium injection amount, and as a result, the physical burden on the subject due to the injection of the contrast medium in the test injection can be reduced.

However, since the test injection is for the purpose of measuring the arrival time of the contrast agent at the imaging site and the measurement of the maximum CT value, it is not necessary to strictly determine the contrast agent injection amount at the time of the test injection. In some cases, the amount of contrast medium injected at the time of test injection may be a fixed value, making it unnecessary to input data such as the weight of the subject. In this case, the test injection amount calculator 145 is unnecessary.

As described above, when the input necessary for performing the test injection is completed, the operator touches the test injection start button 154. Thereby, the chemical injection device 100 starts the test injection when the control unit 141 moves the piston drive mechanism 130 forward. In the control unit 141, a protocol for injecting a contrast agent at a constant injection rate during a predetermined injection time is set as a contrast agent injection protocol. Further, the amount of contrast medium injected is proportional to the moving distance of the piston drive mechanism 130. Therefore, the control unit 141 advances the piston drive mechanism 130 at a constant speed by a distance corresponding to the amount of contrast medium calculated by the test injection injection amount calculation unit 145 during a predetermined injection time. The injection time of the contrast agent can be set in advance according to, for example, the imaging region, but can be changed by the operator as necessary.

Simultaneously with the start of test injection, a test injection start signal is transmitted from the control unit 141 to the CT apparatus 300 via the interface 147. The CT apparatus 300 executes a monitoring scan after a predetermined time has elapsed since the start of test injection. During the monitoring scan, the CT apparatus 300 measures CT values at regular time intervals and displays the results as a graph or an image.

On the other hand, in the chemical injection device 100, when the test injection is completed, the control unit 141 causes the touch panel to display a setting screen 160 for main injection as shown in FIG. On this setting screen 160, a screen for inputting the maximum CT value at the time of test injection is displayed.

If the injection time of the contrast agent is the same, it may be approximated that there is a generally proportional relationship between the injection amount of the contrast agent and the increase in the maximum CT value. Therefore, C _{T is} the increase in the maximum CT value due to the test injection, C _{A is} the increase in the maximum CT value due to the main injection, I _t is the contrast agent injection amount at the test injection, and I is the contrast agent injection amount at the main injection. _{When a} is between these,
C _T : C _A = I _t : I _a
The following proportional expression can be considered.

However, in practice, the imaging region has a certain CT value even when the contrast agent is not injected, and the CT value measured by the CT apparatus 300 is the CT value before the contrast agent is injected. It is a value including. Therefore, the increase in the maximum CT value due to the injection of the contrast agent in the test injection and the main injection is C _t , which is the maximum CT value obtained by the CT apparatus 300 in the test injection, and the target to be obtained by the CT apparatus 300 in the main injection When the maximum CT value is C _a and the CT value before injection of the contrast agent is C ₀ , C _T = C _t −C ₀ , respectively.
C _A = C _a -C ₀
It becomes. From these equations, the proportional equation is
(C _t −C ₀ ) :( C _a −C ₀ ) = I _t : I _a
It can be expressed as. Here, the target maximum CT value C _a is the maximum CT value with which the best contrast effect can be obtained, and this value can be set in advance based on statistical data or the like.

Thus, by utilizing the proportional relationship between the contrast agent injection amount and the maximum CT, the contrast agent injection amount and the maximum CT value obtained by the CT apparatus 300 at that time are known in the test injection. since, it is possible to determine the injection amount of the contrast medium as the target maximum CT value C _a can be obtained in this injection very easily. Specifically, the injection amount calculation unit 146 for main injection uses the maximum CT value C _t obtained by the CT apparatus 300 in the test injection, the target maximum CT value C _a to be obtained by the CT apparatus 300 in the main injection, From the CT value C ₀ before contrast agent injection and the contrast agent injection amount I _t at the time of test injection, the following equation:
I _a = I _t × (C _a −C ₀ ) / (C _t −C ₀ )
Based on the above, the contrast medium injection amount I _a at the time of main injection is calculated.

This contrast medium injection amount at the time of injection of the data necessary to calculate the present injection contrast medium injection amount when the calculated test injection to the target maximum CT value C _a and test injection for injection quantity calculation unit 145 at the time of I _t is stored in the control unit 141 as data. In addition, as the CT value before injection of the contrast agent, an appropriate value corresponding to the imaging region can be stored in advance in the control unit 141 based on statistical data. Accordingly, the operator need only maximum CT value C _t obtained in the test injection to input to the touch panel. Note that the setting screen 160 shown in FIG. 6 displays the proportional expression in which the value to be input and the calculated value are blank. Here, in the displayed proportional expression, for the maximum CT value, for the convenience of inputting the maximum CT value in the test injection, the maximum CT value including the CT value before the contrast agent injection is used instead of the increase in the maximum CT value. The injection amount calculation unit 146 for main injection subtracts the CT value before the contrast agent injection from the input maximum CT value and the set target maximum CT value, respectively. The contrast medium injection amount is calculated.

In addition, in the setting screen 160 for main injection shown in FIG. 6, in addition to the maximum CT value at the time of test injection, an elapsed time from the start of test injection when the maximum CT value is reached by test injection is input as a peak time. It is supposed to be. When the peak time is input, the control unit 141 causes the setting screen 160 to display the imaging start time of the main scan executed by the CT apparatus 300 corresponding to the main injection.

The imaging start time can be, for example, 2 seconds before the CT value peak time. Thereby, since imaging can be performed in a period including the peak time of the CT value, a good contrast effect can be obtained. How many seconds before the peak time of the CT value is started may be determined in advance, but can be changed by the operator as necessary.

In general, when the amount of contrast medium injected increases, the time to reach the maximum CT value tends to be delayed. Therefore, if the imaging timing from the start of contrast agent injection is constant, even though the contrast agent injection amount is different between the test injection and the main injection, the imaging time that the CT apparatus executes in response to the main injection is There may be a deviation from the timing of reaching the target maximum CT value. Therefore, the control unit 141 may correct the peak time of the CT value obtained by the test injection based on the contrast agent injection amount in the main injection calculated by the main injection amount calculation unit 146. In that case, the control unit 141 can set the imaging start time based on the corrected peak time.

When the imaging start time is set, the control unit 141 transmits the data to the CT apparatus 300 through the interface 147. In response to this, the CT apparatus 300 can execute the main scan, for example, for 4 seconds from the imaging start time. Note that the imaging start time after the main injection can be determined in advance in consideration of the difference between the start of the injection of the contrast agent and the arrival of the maximum CT value between the test injection and the main injection. In that case, it is not necessary to input the peak time in the test injection.

As described above, after the maximum CT value and peak time at the time of test injection are input, the operator touches the OK button displayed on the setting screen 160.

When the OK button is touched, the control unit 141 displays a main injection confirmation screen 170 as shown in FIG. 7 on the touch panel, for example. The main injection confirmation screen 170 displays an injection graph representing the relationship between the elapsed time from the start of injection and the injection speed of the chemical solution injected by the main injection. Furthermore, the imaging start time is also displayed on this graph, so that the imaging timing can be seen at a glance.

In this embodiment, the main injection is performed by the same protocol as the test injection in which the contrast medium is injected at a constant injection speed during a predetermined injection time. Here, since the injection amount of the contrast medium is different between the test injection and the main injection, in the main injection, the injection time is the same as the injection time in the test injection, but the injection speed is different from the test injection. Usually, since the amount of contrast medium injected in the main injection is larger than that in the test injection, the contrast medium is injected at a higher injection rate than in the test injection. In this embodiment, after the contrast agent is injected, a predetermined amount of physiological saline is injected at a preset injection rate.

After confirming the main injection confirmation screen 170, the operator touches the main injection start button displayed on the touch panel. When the main injection start button is touched, the control unit 141 controls the two piston drive mechanisms 113 so that the contrast medium and the physiological saline are injected into the subject according to the above-described protocol, whereby the main injection is performed. The

Simultaneously with the start of the main injection, a main injection start signal is transmitted from the control unit 141 to the CT apparatus 300 via the interface 147. The CT apparatus 300 performs the main scan after the start of the main injection after the imaging start time set by the chemical injection device 100 based on the result of the test injection. By the main scan, a CT image of the subject at the target imaging site is captured.

As described above, according to the present embodiment, the contrast agent injection amount in the main injection is determined using the maximum CT value measured in the test injection. The maximum CT value obtained by the test injection reflects individual differences such as the circulating blood volume, cardiac output, and vascular resistance of the test subject. Therefore, it is possible to set the optimum injection amount of the contrast medium according to the individual difference very easily. In addition, since the test injection is a process that is normally performed prior to the main injection in order to measure the time for the contrast medium to reach the imaging region, the number of processes is not newly increased by performing the test injection.

In the present embodiment, an example is shown in which the operator himself inputs the maximum CT value obtained by the test injection necessary for determining the contrast agent injection amount in the main injection. However, for example, the control unit 141 is configured to be able to receive the maximum CT value data from the CT apparatus through the interface 147 after the test injection, and the received maximum CT value data is input to the test injection amount calculation unit 145. It can also be. This eliminates the need for the operator to input the maximum CT value.

Further, in this embodiment, an example in which a contrast medium is injected using a protocol with a constant injection speed has been described. However, in order to obtain a good contrast effect with a smaller amount of contrast medium and / or a predetermined CT value as long as possible. In order to be able to maintain, the injection rate of the contrast agent can be changed over time. Even in this case, in order to be able to obtain the injection amount of the contrast medium in the main injection using the maximum CT value obtained in the test injection, the above-described proportional expression (C _t −C ₀ ): ( C _a −C ₀ ) = I _t : I _a
For example, a protocol in which the tendency of the change in the injection rate with the passage of time is the same between the test injection and the main injection may be set in the control unit 141.

In the above-described embodiment, the example in which the two liquid syringes 200P and 200C are mounted on the injection head 110 has been shown. However, the number of the liquid syringes that can be mounted on the injection head 110 may be one or three or more. It may be. In that case, the concave portions 114, the piston drive mechanisms 130, and the like are provided in a number corresponding to the number of chemical syringes to be mounted. The size of the chemical syringe that can be attached to the injection head 110 is also arbitrary, and the size of the recess 114, the stroke of the rod 131, and the like are set so as to match the size of the chemical syringe to be attached. When mounting a plurality of chemical solution syringes, the sizes of the chemical solution syringes may be different from each other.

DESCRIPTION OF SYMBOLS 100 Chemical solution injection apparatus 101 Injection control unit 110 Injection head 130 Piston drive mechanism 141 Control part 142 Input part 143 Display part 145 Test injection injection amount calculation part 146 Main injection injection quantity calculation part 147 Interface 200C, 200P Syringe 300 CT apparatus 1000 CT system

Claims

In order to capture a CT image of a subject with a CT apparatus, a syringe filled with a contrast agent that changes the CT value of the subject by injection is mounted, and the contrast agent is changed by operating the mounted syringe. In a chemical injection device comprising an injection head for injection and a control unit for controlling the injection head to perform test injection prior to main injection,
Based on the maximum CT value obtained by the CT apparatus by the test injection, the contrast medium injection amount for the main injection is calculated so that the maximum CT value obtained by the main injection becomes a predetermined value. It has an injection amount calculation unit,
The said control part controls the said injection | pouring head so that the quantity of contrast agent calculated by the said injection amount calculating part for main injection may be inject | poured at the time of the said main injection.
The injection amount calculation unit for main injection has the following relational expression I a = I t × (C a −C 0 ) / (C t −C 0 )
(However, the injection amount of the contrast medium in I a is the present injection, I t is the injection amount of the contrast medium in the test injection, C a is the target maximum CT value to be obtained by the CT apparatus in the present injection , C t is the maximum CT value obtained by the CT apparatus in the test injection, and C 0 is the CT value before contrast agent injection.)
The chemical injection device according to claim 1, wherein the injection amount of the contrast medium in the main injection is calculated from the above.
The chemical injection device according to claim 2, wherein the injection protocol of the test injection and the main injection is an injection protocol for injecting a contrast medium at a predetermined injection speed during a predetermined injection time.
4. The apparatus according to claim 1, further comprising an interface that enables transmission / reception of data to / from the CT apparatus, through which the maximum CT value obtained by the test injection is received. The chemical injection device described in 1.
5. The test injection injection amount calculation unit that calculates the injection amount of the contrast agent at the time of the test injection based on at least a part of the body factor of the subject and the liquid chemical factor of the contrast agent. The chemical injection device according to any one of the above.
The control unit further corrects the time from the injection start of the contrast agent to the maximum CT value measured by the CT apparatus by the test injection from the injection amount calculated by the injection amount calculation unit for main injection. The chemical injection device according to any one of claims 1 to 5, wherein the medical solution injection device is configured as follows.