JP2015136416A - Catheter and image diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter for imaging and an image diagnostic apparatus which can identify a structure of a blood vascular system to the same degree as a case in which a contrast medium is administered, without pouring the contrast medium in blood.SOLUTION: A catheter for imaging includes a catheter body and a plurality of linear objects. The catheter body consists of a hollow member. The linear object consists of a slender and flexible member in which at least a part has low X-ray permeability, and is configured so as to be able to protrude from the tip of the catheter body.

Description

  Embodiments described herein relate generally to a catheter and a diagnostic imaging apparatus.

  In an X-ray examination of a circulatory organ that is performed by inserting a catheter body into a blood vessel, a contrast medium is flowed from the distal end of the catheter body to contrast the blood vessel lumen so that the blood vessel can be visually recognized on the X-ray image. (For example, refer to Patent Document 1).

  This is because blood vessels cannot be visually recognized on an X-ray image unless contrast is performed. The contrast medium that has flowed into the blood vessel circulates through the blood vessels throughout the body on the bloodstream, and is gradually filtered by the kidneys and gradually moved into the urine, whereby the concentration of the contrast medium in the bloodstream gradually decreases.

JP 2006-34952 A

  However, the filtration of contrast agents places a heavy burden on the kidneys. For this reason, it is contraindicated to administer a large amount of contrast medium particularly in patients with renal disease, and it is desirable to reduce the amount of contrast medium used as much as possible even in patients with normal renal function.

  There are also economic problems. The upper limit of the cost of the contrast agent that can be covered by insurance for a single examination (or interventional radiology (IVR)) is set. Will be taken out by the hospital (or patient burden).

Because of these circumstances, physicians struggle to successfully distribute a limited amount of contrast agent.
However, there is a problem in that there is a case where it is necessary to carefully check the structure of the vascular system during the examination (IVR).

  This embodiment solves the above-described problem, and does not cause the contrast medium to flow into the blood, and allows the structure of the vasculature to be identified to the same extent as when the contrast medium was administered. An object of the present invention is to provide a catheter and a diagnostic imaging apparatus.

  In order to solve the above problems, the catheter of the embodiment has a catheter body and a plurality of linear bodies. The catheter body is composed of a hollow member. The linear body is elongated and flexible, and at least part of the linear body is made of a member having low X-ray transparency.

1 is a configuration block diagram of an X-ray diagnostic apparatus according to a first embodiment. The enlarged view of a catheter. The figure of the linear body fixed to the front-end | tip of a wire. The figure of the linear body protruded from the state shown in FIG. The figure of the catheter which has three linear bodies. The figure of the linear body protruded from the front-end | tip of a catheter main body. The figure of the linear body protruded from the state shown in FIG. The figure of the linear body protruded from the state shown in FIG. The figure of the linear body protruded from the state shown in FIG. The figure of one image created from four images. The figure of one image created from n images. The figure of the linear object concerning a comparative example. The figure of the linear body protruded from the state shown in FIG. The figure of the linear body protruded from the state shown in FIG. The figure of the catheter concerning a 2nd embodiment. The figure of the linear body protruded from the state shown in FIG. The figure of the linear body protruded from the state shown in FIG. FIG. 3 is a configuration block diagram of an image processing unit. The figure for demonstrating an image process part. The figure for demonstrating the other example of an image process part. The figure for demonstrating a position alignment process part. The figure for demonstrating a position alignment process part. The schematic diagram which shows the outline of the blood vessel of the aortic root part. In the comparative example, the schematic diagram of the aortic root part observed using the contrast agent. The figure showing the blood vessel which has a branch part using a catheter. The figure of the catheter concerning a 3rd embodiment. The figure of the linear body protruded from the state shown in FIG.

  An example of an embodiment of a catheter will be described in detail with reference to the drawings.

  The catheter according to this embodiment is applied in the fluoroscopic catheterization performed by inserting into the body of a subject under fluoroscopy. An X-ray diagnostic apparatus, which is an example of an image diagnostic apparatus, is used for catheterization under fluoroscopy. The X-ray diagnostic apparatus displays a series of X-ray images acquired in time series by X-ray fluoroscopic catheterization as a moving image and / or displays an X-ray image selected from the series of X-ray images. Is.

  In this embodiment, the image data processed by the X-ray diagnostic apparatus is formed by pixels such as pixels and voxels, and data is formed by giving values (pixel values) to the respective pixels. It is. An image is a representation of this image data so as to be visible by a predetermined computer program. As described above, the image data and the image have a one-to-one correspondence, and therefore, “image” and “image data” are not distinguished.

[First Embodiment]
A first embodiment will be described. First, the configuration of the X-ray diagnostic apparatus will be described. Next, an example of a catheter imaged by the X-ray diagnostic apparatus will be described.

〔Device configuration〕
The configuration of the X-ray diagnostic apparatus according to this embodiment will be described. A configuration example of this X-ray diagnostic apparatus is shown in FIG. This X-ray diagnostic apparatus has a mechanical configuration similar to that of the prior art.

  As shown in FIG. 1, the X-ray diagnostic apparatus includes a top plate 2, a C arm 3, an X-ray tube 4, an X-ray diaphragm 5, an X-ray detector 6, a drive mechanism 8, a high voltage generator 9, and an aperture controller. 10, an arithmetic control device 20, a display unit 31, and an operation unit 32. In addition, the arithmetic and control unit 20 includes a system control unit 21, a storage unit 22, an image processing unit 23, and a display control unit 24.

  The subject 1 represents a patient who is subjected to catheterization under fluoroscopy. The subject 1 is placed on the top 2. The top plate 2 is a part of a couch device (not shown). The bed apparatus is provided with a drive mechanism for moving the top board 2. In this embodiment, the subject 1 is placed so as to lie on the top 2. Some X-ray diagnostic apparatuses are provided with a standing table for supporting a subject in a standing position. However, in X-ray fluoroscopic catheterization, a subject that is normally supported in a supine state on a top plate is used. The specimen is treated.

  The C arm 3 is a support member formed in a substantially “C” shape. An X-ray tube 4 and an X-ray diaphragm 5 are supported on one end side of the C arm 3, and an X-ray detector 6 is supported on the other end side. Thereby, the X-ray tube 4 and the X-ray diaphragm 5 and the X-ray detector 6 are arranged at positions facing each other with the subject 1 interposed therebetween.

  The C arm 3 is movably held by a drive mechanism 8. The drive mechanism 8 moves the C arm 3 under the control of the arithmetic and control unit 20, thereby changing the positions and inclination angles of the X-ray tube 4, the X-ray diaphragm 5 and the X-ray detector 6.

  The X-ray tube 4 generates X-rays 7 when a high voltage is applied from the high-voltage generator 9. The X-ray diaphragm 5 has diaphragm blades that regulate the irradiation range (solid angle and cross-sectional shape) of the X-ray 7 generated from the X-ray tube 4. The aperture controller 10 changes the irradiation range of the X-ray 7 by moving the position of the aperture blade. The operations of the high voltage generator 9 and the aperture controller 10 are controlled by the arithmetic and control unit 20.

  The X-ray 7 whose irradiation range is regulated by the X-ray diaphragm 5 is irradiated to the subject 1. The X-ray 7 that has passed through the subject 1 is projected to the X-ray detector 6. The X-ray detector 6 detects the X-ray 7, converts the detection result into an electric signal, and transmits it to the detection control unit 11. The detection control unit 11 transmits this electric signal to the arithmetic control device 20. The detection control unit 11 controls the operation of the X-ray detector 6.

  The X-ray detector 6 detects a transmitted X-ray from the subject 1, converts it into an electrical signal and outputs it, for example, a flat panel detector (FPD) or an image intensifier (I). .. I.).

  In this embodiment, the X-ray tube 4 is controlled to irradiate the pulse X-ray 7 at a predetermined time interval. This time interval is set to, for example, about (1/30) second to (1/5) second (5 to 30 irradiations per second). Note that the X-ray diagnostic apparatus can perform irradiation at a maximum of several tens of times / second, for example, but this time interval is selected in order to reduce the X-ray exposure to the subject 1 and the operator. Thereby, a moving image with a frame rate of about 5 to 30 frames / second is obtained. The obtained image (frame) is stored in the storage unit 22. Instead of repeatedly irradiating pulsed X-rays in this way, it is also possible to irradiate X-rays continuously.

  The arithmetic and control unit 20 controls each part of the X-ray diagnostic apparatus and executes various arithmetic processes. The arithmetic and control unit 20 has the same configuration as a general computer, for example. As an example, the arithmetic and control unit 20 includes a microprocessor, a storage device (RAM, ROM, hard disk drive, etc.), a communication interface, and the like. An operation device, an input device, and a display device are connected to the arithmetic control device 20.

  A system control unit 21 in the arithmetic and control unit 20 controls each unit of the X-ray diagnostic apparatus. One example is as follows: the drive mechanism 8 is controlled to move the C-arm 3; the high-voltage generator 9 is controlled to change the X-ray conditions (X-ray 7 dose, frame rate, etc.) For example, the X-ray dose increase / decrease adjustment described later is performed; the aperture control unit 10 is controlled to change the irradiation range of the X-ray 7; the detection control unit 11 is controlled to control the operation of the X-ray detector 6. Let it be done. Further, the system control unit 21 controls each unit of the arithmetic and control unit 20.

  The image processing unit 23 forms an image (digital image data) of the subject 1 based on the electrical signal transmitted from the X-ray detector 6 via the detection control unit 11. The image processing unit 23 performs various image processing on the image. Details of the image processing unit 23 will be described later.

  The display control unit 24 displays information on the display unit 31 under the control of the system control unit 21. The display unit 31 is configured using a display device such as a liquid crystal display (LCD) or a CRT (Cathode Ray Tube).

  The operation unit 32 is used for operation of the X-ray diagnostic apparatus and information input. The operation unit 32 includes operation devices and input devices such as a keyboard, a mouse, a control panel, and a pedal operation unit. The pedal operation unit outputs an instruction signal for starting or stopping X-ray irradiation, and outputs an instruction signal for increasing or decreasing the X-ray dose.

〔catheter〕
The configuration of the X-ray diagnostic apparatus has been described above. Next, a catheter imaged by the X-ray diagnostic apparatus will be described with reference to FIG. FIG. 2 is an enlarged view of the catheter.

  As shown in FIG. 2, the catheter 50 includes a catheter main body 51 and a linear body 52. The catheter body 51 is a hollow soft tube used for medical purposes.

[Configuration of linear body]
Next, an example of the linear body 52 will be described with reference to FIGS. FIG. 3 is a diagram of a linear body fixed to the distal end of the wire 56, and FIG. 4 shows a state in which the linear body 52 protrudes from the distal end of the catheter main body 51 by advancing the wire 56 in the catheter main body 51. FIG.

  As shown in FIGS. 3 and 4, the linear body 52 includes a linear portion 53 protruding from the distal end of the catheter main body 51 through the inside of the catheter main body 51, and a distal end 54 having a diameter larger than the diameter of the linear portion. It consists of. The linear body 52 is fixed to the tip of a wire 56 fed through the catheter body 51. The linear body 52 may be formed integrally with the wire 56. By operating the proximal end side of the wire 56 by the doctor, the linear body 52 can be inserted into and removed from the distal end of the catheter body 51 into the blood vessel.

  The linear body 52 is an elongated linear object that is very flexible and at least partially has low X-ray transparency. The flexibility and slenderness are such that the linear body 52 can migrate along the bloodstream, and the low X-ray permeability is such that the linear body 52 can be radiographed. The linear body 52 is a component having a contrast effect (a substance containing an element with a large atomic number as a constituent element and does not damage the human body even if a trace amount is eluted in the blood. For example, gold powder, iodine contrast agent Cord-like or whip-like sonde made of a flexible material or composite material. It is sufficient that only the tip 54 of the linear body 52 is made of a material having low X-ray transparency, and the entire linear body 52 need not be made of such a material.

  In order to prevent the formation of thrombus, the surface of the linear body 52 is finished very smoothly. The knowledge used in the known catheter technology can be directly applied to the material used for the surface. For example, you may comprise so that the chemical | medical agent which prevents blood coagulation may penetrate | invade into the surface further.

  As shown in FIG. 2, the tip 54 of the linear body 52 may be slightly inflated. By doing so, movement due to blood flow is likely to occur and the movement can be easily identified. The reason why the tip 54 of the linear body 52 is thick is that it is easy to move due to resistance of blood flow and that X-ray permeability (inversely proportional to the index of thickness) is lowered.

  FIG. 5 is a diagram of a catheter having three linear bodies. FIG. 5 shows that the distal end of the catheter body 51 is extended in the internal carotid artery (a large blood vessel that sends blood to the brain) and linear bodies 52 (three in the figure) are extended into the blood vessel. In FIG. 5, the three linear bodies 52 are respectively shown by a solid line, a dashed-dotted line, and a broken line. The upper side of FIG. 5 is the downstream side of the blood flow.

  As shown in FIG. 5, a bundle of a plurality of linear bodies 52 may be used. By using a plurality, it becomes easy to determine the branching portion of the blood vessel. Further, by making the length of each linear body 52 (the length protruding from the distal end of the catheter body 51) different, it can be easily inserted into the catheter body 51. This is because each tip 54 having a bulge can be inserted into the catheter body 51 in order from the longest one.

The linear body 52 is moved by blood flow and moves around in the blood vessel. Accordingly, the lumen of the blood vessel can be identified as a range in which the linear body 52 moves around.
In addition, when an operation for taking in and out the linear body 52 from the distal end of the catheter body 51 is performed, the linear body 52 may be sucked into one of the branches at the branching portion of the blood vessel. At this time, if the linear body 52 is projected longer from the distal end of the catheter body 51, the linear body 52 penetrates deeper into the branch, so that it is possible to distinguish where the branch exists when X-rays are taken. It is done.

  However, particularly in the examination of the chest, the image of the linear body 52 moves violently due to the patient's breathing and heartbeat, so that it is difficult to clearly see it on the image. If the linear body 52 is thickened, it can be easily seen on the image, but then the flexibility of the linear body 52 is lost, or it becomes difficult to enter the blood vessel branch.

  In addition, when blood vessels hardly move relative to the X-ray diagnostic apparatus such as imaging of cerebral blood vessels, there is a weakness that there is little knowledge that can be obtained by simply viewing one still image.

(Image processing unit)
Hereinafter, the image processing unit 23 that enables the shape of the blood vessel lumen to be visually recognized on an image even for the linear linear body 52 will be described with reference to FIGS. 6 to 9.

6 is a diagram of a linear body projecting from the distal end of the catheter body, FIG. 7 is a diagram of a linear body projecting from the state shown in FIG. 6, and FIG. 8 is a linear body projecting from the state shown in FIG. FIG. 9 is a diagram of a linear body protruding from the state shown in FIG.
The following discloses a method for solving the above weak points by combining a plurality of images when a blood vessel hardly moves relative to the X-ray diagnostic apparatus, such as imaging of a cerebral blood vessel.

  The linear body 52 moves around by the blood flow of the artery. As the linear body 52 protrudes longer from the catheter body 51 (FIGS. 6 to 9), it is caused to flow downstream by the blood flow, and sometimes enters the branch at the bifurcation of the blood vessel.

  The linear body 52 is repeatedly projected from the distal end of the catheter main body 51 or stored repeatedly, and during that time, moving images are taken with X-rays. Since the patient is stationary, it is the image of the linear body 52 and the image of the catheter body 51 that are moving on the captured moving image. Therefore, for each pixel, the value at the time point when the image becomes darkest with time (the most X-rays are absorbed) is taken out to create one image. This is called a bottom map image.

  The image processing unit 23 creates an image that takes the lowest (dark) pixel value among a predetermined number of images (for example, four images).

Pixels at (x, y) in the bottom map image, where p (k, x, y) is the pixel value of the pixel at each position (x, y) in k images (k = 1 to k) Is represented by the following equation.

  By creating this bottom map image, it is possible to know the existence distribution of the linear bodies 52 at the time of photographing k images, thereby obtaining an image representing the blood flow.

  Note that the bottom map image may be an image that is created by taking out the values at the time when the image becomes darkest over time for each pixel. For example, the first one image is set as a bottom map image, the pixel value of each pixel is held, and then the pixel value of each pixel of the image that is sequentially captured is compared with the pixel value of each pixel of this bottom map image. If it is low, it is held as the pixel value of that pixel, so that the bottom map image is updated, so that one bottom map image is created from the k images, and the line shape at the shooting time of the k images The existence distribution of the body 52 may be known.

  FIG. 10 is a diagram of one bottom map image obtained from the four images shown in FIGS. 6 to 9, and FIG. 11 is a diagram of one bottom map image obtained from a number of moving image frames. Since the linear body 52 cannot enter where there is no blood vessel, the bottom map image depicts the shape of the blood vessel lumen almost accurately.

  If the combination of the linear body 52 and the present image processing is used, the characteristics of the blood vessel lumen can be confirmed any number of times without using a contrast agent (and without adversely affecting the renal function of the patient).

  Of course, when it is desired to observe very fine properties of blood vessels, the linear body 52 may be insufficient, and in such a case, a conventional contrast agent must be used. However, conventionally, in many cases where a contrast agent is used, the purpose is simply to know the approximate position and thickness of a blood vessel, the position of a branching portion, and the like. For such a purpose, it is sufficient to use the linear body 52 instead of the contrast agent. For this reason, the usage-amount of a contrast agent can be reduced significantly.

[Second Embodiment]
12 is a diagram of a linear body according to a comparative example, FIG. 13 is a diagram of a linear body protruding from the state shown in FIG. 12, and FIG. 14 is a diagram of the linear body protruding from the state shown in FIG. .
In FIG. 12, the distal end of the catheter body 51 inserted from the femoral artery is placed immediately downstream of the aortic valve (the valve connecting the heart to the aorta), and the linear bodies 52 (three in the figure) are extended into the blood vessel. Where. The linear body 52 moves around by the blood flow of the aorta. As the linear body 52 protrudes longer from the catheter body 51 (FIGS. 13 to 14), it is caused to flow downstream by the blood flow, but the linear body 52 continues to fluctuate violently during that time.

  However, the position of the blood vessel image itself moves on the X-ray image by sudden patient movement (hereinafter referred to as “body movement”) such as breathing and heartbeat of the patient or coughing. For this reason, in the technique of creating one bottom map image from a plurality of images by the image processing unit 23, if the movements of the linear bodies 52 are integrated, a blood vessel image that is extremely blurred is obtained.

  This problem is solved by combining an image processing technique (hereinafter referred to as “stabilizer”) that allows a blood vessel image to be always drawn at a substantially constant position on an X-ray image.

  Next, a second embodiment of the catheter will be described with reference to FIGS. 15 to 25.

(Image processing unit)
First, a technique of a stabilizer included in the image processing unit 23 will be described with reference to FIGS. 15 to 17.

  15 is a view of the catheter, FIG. 16 is a view of the linear body 52 protruding from the state shown in FIG. 15, and FIG. 17 is a view of the linear body 52 protruding from the state shown in FIG. FIGS. 15 to 17 show the guide wire 61 having two markers 62 in addition to the linear body 52 placed in the blood vessel. The guide wire 61 is provided at a position where the linear body 52 migrates from the distal end of the catheter body 51.

  As shown in FIGS. 15 to 17, the guide wire 61 is provided in the vicinity of the distal end of the catheter body 51. Needless to say, the guide wire 61 may be introduced by using the same catheter body 51 as the linear body 52, but in FIG. 15 to FIG. 17, the guide wire 61 is fed from another catheter (not shown). I'm drawing. Guide wire 61 enters the heart lumen through the opening of the aortic valve. Then, the guide wire 61 is supported by the aortic valve and hardly moves relative to the heart and the aortic root.

  In this way, by installing the guide wire 61 that hardly moves with respect to the blood vessel and recognizing the image of the marker 62 on the guide wire 61 by image processing, the patient's body movement (movement due to breathing or heartbeat or sudden movement) The amount of change in the position of the image (translation and rotation angle) due to the movement of the image can be measured. By rotating and translating the image accordingly, the patient's body movement can be canceled (Stent Stabilizer ( (sent stabilizer) technology).

  Further, even when the guide wire 61 without the marker 62 is placed, the image of the characteristic part of the guide wire 61 is recognized by image processing in the same manner as when the image of the marker 62 is image-processed. Body motion can be counteracted (wire stabilizer technique).

  Of course, when there is another characteristic image that can be easily identified on the image, such as a marked calcification image, or a marker artificially placed in or near the blood vessel, such a guide wire 61 is used. Even without using, the patient's body motion can be canceled by rotating and translating the image so that this characteristic image always remains stationary.

(Details of stabilizer processing)
Two markers 62 are provided on the guide wire 61 (see FIG. 15).
Each time a new frame is stored in the storage unit 22, the wire specifying unit 41 detects the coordinates of the marker 62 in the new frame.

For example, as shown in FIG. 19, the system control unit 21 performs control so that the first frame generated first and stored in the storage unit 22 is displayed on the monitor of the display unit 31.
The doctor who refers to the first frame designates the two markers 62 in the first frame via the operation unit 32 as shown in FIG. As a result, the wire specifying unit 41 detects the coordinates of the two markers 62 in the first frame.

  After that, as shown in FIG. 19, the wire specifying unit 41 sets a rectangle centered on the coordinates of the two markers 62 designated in the first frame as a ROI (Region of Interest), and sets the inside of the set ROI. A pattern similar to the above pattern is extracted for each genuine image sequentially generated by, for example, the cross-correlation method, and the coordinate having the highest cross-correlation value is detected as the coordinate of the marker 62.

  In addition, although FIG. 19 demonstrated the case where two markers 62 were designated by the doctor, it is not limited to this, and may be a case where one marker 62 is designated by the doctor. In this case, even in the first frame, the wire specifying unit 41 executes the cross-correlation method using the ROI set from the coordinates of the designated marker 62 to detect the coordinates of the other marker 62.

  In contrast, another example of the wire specifying unit 41 will be described with reference to FIG. The wire specifying unit 41 detects the coordinates of the guide wire 61 using a teacher image indicating the shape and brightness characteristics of the guide wire 61 attached to the catheter body 51 that is actually used for treatment in the X-ray image.

  For example, as shown in FIG. 20, an X-ray image of the guide wire 61 is separately stored as a teacher image, and the wire specifying unit 41 extracts a pattern similar to the teacher image for each new image, and extracts the extracted guide wire. An area having the highest similarity is searched from the 61 candidate areas, and the coordinates of the guide wire 61 are detected.

  Returning to FIG. 18, the alignment processing unit 43 uses the coordinates of the marker 62 already detected by the wire specifying unit 41 in the first frame, which is the X-ray image generated first, as the reference coordinates, and the second and subsequent frames. Image movement processing such as translation and rotation from the second and subsequent new images and image deformation processing such as affine transformation so that the coordinates of the marker 62 detected by the wire specifying unit 41 in the new image coincide with the reference position. A corrected image is created.

  For example, as shown in FIG. 21, the alignment processing unit 43 uses the marker 62 in which the coordinates of the marker 62 detected in the X-ray image of the second frame generated as the new image are already detected in the first frame. The corrected image 2 is generated by image deformation from the second frame so as to coincide with the coordinates (reference coordinates).

  Then, for the new image after the third frame, the alignment processing unit 43 uses the coordinates of the marker 62 in the correction image generated by itself from the X-ray image generated immediately before the new image as a reference coordinate. Generate. For example, as illustrated in FIG. 22, the alignment processing unit 43 sets the coordinates of the marker 62 detected in the third frame so that the coordinates of the marker 62 of the corrected image 2 generated from the second frame match. A corrected image 3 is generated from the three frames by image deformation.

  By sequentially displaying the corrected images 3 generated in this way, it is possible to display a moving image in which the position of the marker 62 is substantially constant.

  Although the stabilizer process using a marker has been described above, a stabilizer process without using a marker may be used. For example, a characteristic curve portion (bending along the blood vessel traveling, etc.) is extracted from the travel shape of the guide wire 61 and the like, and the parallel movement and rotation are performed so that the curve portions extracted from the images of the respective frames are almost at the same position. Stabilizer processing can be performed by performing image movement processing such as movement and image deformation processing such as affine transformation to generate a corrected image.

  Thus, it is preferable that one bottom map image is created from a plurality of images by the image processing unit 23 after frame alignment (stabilizer processing) is performed using the marker image. In this bottom map image, since the image of the linear body 52 does not move due to body movement, the shape of the blood vessel lumen can be depicted almost accurately.

  When the linear body 52 is used, there is a case where an advantage that it is easy to specify the branching portion of the blood vessel may occur as compared with the case where the contrast medium is used. An example of this will be described with reference to FIGS. FIG. 23 is a schematic diagram showing a schematic shape of a blood vessel at the aortic root, and FIG. 24 is a schematic diagram of the aortic root observed using a contrast medium in a comparative example. In FIG. 23, the aorta, coronary artery and aortic root are indicated by “AO”, “AR” and “BS”. The base BS of the coronary artery AR branched from the aorta AO is indicated by an arrow in FIG.

  In the valvular disease of the aortic valve, there is an operation in which a prosthetic valve is installed via the inside of the blood vessel using the catheter body 51. At that time, if the position where the artificial valve is placed is not appropriate and the artificial valve blocks the base portion BS of the coronary artery AR, blood flow to the myocardium is blocked and myocardial infarction occurs. That is, it is very important to determine the position of the root BS of the coronary artery AR before installing the artificial valve.

  However, when this portion is observed using a contrast medium, as shown in FIG. 24, the outline of the aorta AO and the coronary artery AR can be identified by the contrast medium distributed in their lumens. It is not possible to observe where the part BS is.

  In that case, it is necessary to search for the root portion BS of the coronary artery AR by inserting a guide wire 61 separately and invading the coronary artery AR. However, since this operation must be performed in a state where the origin BS of the coronary artery AR is not clearly known, it takes time to find the origin BS of the coronary artery AR. As a result, the operation time is extended and the amount of X-ray exposure increases, so that the physical burden on the patient increases, the burden on the mind and body of the doctor, and the economic burden on the hospital due to a decrease in equipment operation rate. .

  FIG. 25 is a view showing a blood vessel having a bifurcation using a catheter. When the linear body 52 is operated to repeatedly project / store, the linear body 52 is occasionally absorbed into the coronary artery. It can be seen that if it is sufficiently projected at that time, it is clearly drawn into the coronary artery AR (arrow A in FIG. 25).

Here, when the linear body 52 is slowly housed, the movement of the tip of the linear body 52 becomes irregular immediately after passing through the root BS (arrow B in FIG. 25) of the coronary artery AR (because the For example, the coronary artery exits and enters the aortic lumen and is swung by strong blood flow.) By observing this, it is possible to determine where the root of the coronary artery is.
In this way, the linear body 52 is not only a substitute for the contrast agent, but also exhibits an effect of easily and reliably identifying a blood vessel bifurcation that is difficult to observe by contrast enhancement using the contrast agent.

[Third Embodiment]
Next, a catheter according to a third embodiment will be described with reference to FIGS. Note that in the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, description thereof is omitted, and different configurations are mainly described.

  In the third embodiment, the catheter has a guide. The guide has a tube shape and is inserted into the catheter body 51.

  26 is a view of the guide fed to the distal end of the catheter body 51 and the linear body 52 in a state where it is not projected from the distal end of the guide. FIG. 27 is a linear body that is projected from the state shown in FIG. FIG. As shown in FIGS. 26 and 27, a sheath 71 is provided as an example of a guide. The sheath 71 is disposed so as to slightly protrude from the distal end of the catheter body 51. A linear body 52 is disposed in the tube of the sheath 71. The linear body 52 has a linear portion 53, a distal end 54, and a proximal end 55. The distal end 54 is provided at one end of the linear portion 53, and the proximal end 55 is provided at the other end of the linear portion 53. The proximal end 55 has a larger diameter than the linear portion 53.

  The distal end 72 of the sheath 71 has an opening that passes through the linear portion 53 of the linear body 52 and does not pass through the proximal end 55. Accordingly, the linear body 52 is configured to protrude from the distal end of the sheath 71 or to be accommodated.

  The linear body 52 is fed as follows. (1) The physiological saline may be inserted into the sheath 71 while flowing (the flow direction is indicated by an arrow in FIG. 27). At this time, the sheath 71 is sent to the vicinity of the distal end of the catheter body 51 in advance. (2) Alternatively, the linear body 52 may be housed in the sheath 71 with relatively low flexibility, and may be projected from the sheath 71 after being sent to the vicinity of the distal end of the catheter body 51.

  In addition, the mechanism for projecting and storing the linear body 52 is provided by separately providing a wire that reaches the inside of the sheath 71, and by sending / retracting the wire a little, or a liquid (saline) Conventional techniques such as by pouring into the sheath 71 / withdrawing the liquid can be applied. The direction in which the liquid is drawn is indicated by arrows in FIG. As a conventional technique, for example, a technique disclosed in Japanese Patent Application Laid-Open No. 2011-147791 in which physiological saline is flowed between a sheath and a guide wire assembly can be applied.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Subject 2 Top plate 3 C arm 4 X-ray tube 5 X-ray aperture 6 X-ray detector 7 X-ray 8 Drive mechanism 9 High voltage generator 10 Aperture control unit 20 Arithmetic control unit 21 System control unit 23 Image processing unit 24 Display control section 31 Display section 32 Operation section 51 Catheter body 52 Linear body 53 Linear section of linear body 54 Linear body distal end 55 Linear body proximal end 56 Wire 61 Guide wire 62 Marker 71 Sheath 72 Sheath distal end

Claims (8)

A catheter body composed of a hollow member;
A plurality of linear bodies configured to be elongated, flexible, at least partly made of a member having low X-ray permeability, and projectable from the distal end of the catheter body;
A catheter characterized by comprising:   The catheter according to claim 1, wherein the linear body is configured to be inserted and removed from a distal end of the catheter body.   The catheter according to claim 1 or 2, wherein at least two of the linear bodies protrude from the distal end of the catheter body.   The tip part of the said linear body is comprised from the site | part of the vicinity of this tip part, and is comprised with the member with low X-ray permeability, The one in any one of Claims 1-3 characterized by the above-mentioned. The catheter described.   The linear body is attached to a tip of a wire fed through the catheter main body, and the linear body can be inserted into and removed from the distal end of the catheter main body by operating the wire. The catheter according to any one of claims 1 to 4. The tubular guide inserted into the catheter main body, and the linear body is configured to be movable along with movement of the liquid in the guide. Catheter according to any one of the above. X-ray irradiation means for irradiating the subject into which the catheter body according to any one of claims 1 to 6 is inserted with X-rays;
A detector for detecting X-rays transmitted through the subject;
An image that compares the image values at each position of the plurality of frame images detected by the detector and generates a bottom map image having the lowest pixel value among the pixels of the plurality of frame images as the pixel value at each position. An image diagnostic apparatus comprising: a processing unit. The image processing means includes
Extraction means for extracting a marker placed in the vicinity of the catheter body from the image;
Image alignment means for aligning a plurality of frame images so that the positions of the markers match,
8. The diagnostic imaging apparatus according to claim 7, wherein the bottom map image is generated based on the aligned images of a plurality of frames.

Images