JP2003033437A - Catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure the diameter of a blood vessel by using a angiography catheter. SOLUTION: The catheter 5 injects a contrast agent into the blood vessel and measures the diameter of the blood vessel. An index 6 for displaying the outer diameter of the catheter 5 is provided in an image which is photographed on the outer periphery of the catheter 5 together with the blood vessel. The index 6 contains platinum rings 6a, 6b. The index 6 can be used to display the predetermined length of the catheter 5. In this case, the space between the platinum rings 6a, 6b is suitably adjusted and the gap between the platinum rings 6a, 6b is used as an index for visual recognition of inclination, which is capable of visually recognizing the inclination of the catheter 5 in the image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter, and more particularly to a structure of a catheter for measuring the diameter of a blood vessel by inserting it into a blood vessel and injecting a contrast agent from the tip of the blood vessel. .

[0002]

2. Description of the Related Art In recent years, a method of injecting a contrast medium into a blood vessel and performing X-ray imaging of the blood vessel has been used as a method for examining the morphology of the blood vessel. A contrast catheter is used.

A cardiac catheterization method will be described below as an example of an inspection method using this catheter.

FIG. 6 schematically shows the heart 1 and the ascending aorta 2 inside the human body. The heart 1 is connected to the superior vena cava (not shown), the inferior vena cava (not shown) and the ascending aorta 2, and around the heart 1 there is a coronary artery for supplying nutrients to the cells of the heart 1. It is stretched around. As shown in FIG. 6, the coronary arteries include a left coronary artery 3 and a right coronary artery 4, which extend along the heart 1 from the vicinity of the base of the ascending aorta 2.

When performing a contrast examination of the left coronary artery 3 by the cardiac catheterization method, the catheter 5 is guided from the artery located at the crotch or the like to the ascending aorta 2 and the left coronary artery located at the sinus of Valsalva as shown in FIG. The tip portion of the catheter 5 is inserted into the vein of the artery 3. Then, imaging with X-rays is performed while injecting a contrast agent from the tip portion of the catheter 5.

When performing a contrast examination of the right coronary artery 4,
The tip portion of the catheter 5 may be arranged near the ostium of the right coronary artery 4, and imaging with X-ray may be performed while injecting a contrast agent from the tip portion.

[0007]

When performing intravascular treatment, the diameter of the blood vessel is discriminated in order to grasp the degree of stenosis in the lesion of the blood vessel such as the coronary artery. The blood vessel diameter is determined by, for example, analyzing the image of the blood vessel portion selected by the doctor, extracting the contour of the blood vessel portion, and performing the division based on the experience of the doctor. Therefore, the calculation error of the blood vessel diameter is large, and the blood vessel diameter cannot be measured with high accuracy.

Therefore, a contrast agent is injected into a blood vessel, X-ray imaging is performed, an image recorded on a cine film or the like is captured as a digital image, and a contour of a predetermined portion of the blood vessel in this image is automatically extracted. A system for automatically measuring the blood vessel diameter based on the catheter diameter has been developed. With such a system, it is possible to improve the measurement accuracy of the blood vessel diameter as compared with the conventional method described above.

However, the conventional catheter 5 used in this system does not have an index for displaying its outer diameter, and the contour of the catheter 5 is not clear in the above-mentioned image. It was difficult to accurately determine the catheter diameter. Therefore, it has been difficult to measure the blood vessel diameter with high accuracy based on the catheter diameter. In particular, when the image is magnified by bringing the X-ray generator close to the human body, it is more difficult to determine the catheter diameter on the magnified screen, and the above problem becomes remarkable.

The heart 1 is constantly beating, and along with it, blood vessels such as coronary arteries surrounding the heart 1 are also constantly moving. The image in which the catheter 5 is projected together with the blood vessel is
Since it captures the instantaneous state of the blood vessel and the catheter 5, the blood vessel and the catheter 5 may be projected in an inclined state.

However, in the conventional image, it was not possible to grasp whether the blood vessel or the catheter 5 was tilted.
Since the length of the predetermined portion of the catheter 5 that appears in the image varies depending on whether the catheter 5 is tilted or not, it is possible to measure the blood vessel diameter with high accuracy based on the length of the predetermined portion of the catheter 5. It was difficult.

The present invention has been made to solve the above problems. An object of the present invention is to measure a blood vessel diameter with high accuracy using an angiography catheter.

[0013]

The catheter according to the present invention is for injecting a contrast medium into a blood vessel and measuring the diameter of the blood vessel. In one aspect, on the outer circumference of the catheter,
An outer diameter display index is provided for displaying the outer diameter of the catheter in the image taken together with the blood vessel.

By thus providing the index for displaying the outer diameter, the outer diameter of the catheter can be displayed in the image showing the catheter together with the blood vessel. Thereby, the outer diameter of the catheter shown in the image can be determined, and the diameter of the desired portion of the blood vessel can be measured with high accuracy using the outer diameter value of the catheter.

The index for displaying the outer diameter includes first and second members which are mounted on the outer periphery of the catheter with a space therebetween and are made of a material which is less likely to transmit X-rays than the material of the catheter. The outer diameter of the catheter may be displayed depending on the position of the gap between the second members. In addition, as a specific material example of the first and second members, for example, a printable material containing metal, barium-containing resin, or lead can be cited.

Since the first and second members can be visually recognized in the above image, the gap between the first and second members can also be visually recognized. Therefore, by changing the position of the gap according to the outer diameter of the catheter, the outer diameter of the catheter can be determined by confirming the position of the gap on the image.

In another aspect of the catheter according to the present invention, a length display index for displaying the length of a part of the catheter in an image taken together with a blood vessel on the outer periphery of the catheter, and in the above image, An inclination visual indicator for making the inclination of the catheter visible.

By thus providing the length display index, the actual length of the predetermined portion of the catheter in the above image can be known. At this time, it is possible to determine whether or not the catheter is tilted in the above image by providing the catheter with a tilt visualizing indicator. Thereby, the blood vessel diameter can be measured with high accuracy by using the length of the predetermined portion when the catheter is not tilted. By using together with the above-mentioned outer diameter display index, the outer diameter of the catheter and the length of a part of the catheter can be selectively used as necessary, and the blood vessel diameter can be measured easily and accurately. .

The length display index includes first and second members, which are mounted on the outer circumference of the catheter with a space therebetween and are less likely to transmit X-rays than the material of the catheter. Includes a gap between the first and second members.

As described above, by mounting the first and second members on the outer circumference of the catheter with a space, the first and second members are attached.
The length of the predetermined portion of the catheter in the above image can be measured by measuring the total length of the first and second members including the distance between the members. Then, the diameter of a predetermined portion of the blood vessel on the image can be measured based on this length. Here, the actual length of the predetermined portion of the catheter on the image can be determined by changing the position of the gap between the first and second members depending on the total length. On the other hand, by appropriately adjusting the gap between the first and second members, when the catheter is tilted by a predetermined angle or more, the first and second members appear to overlap in the above image, and the catheter is not tilted by a predetermined angle or more. In addition, the gap can be made visible in the above image. Thereby, it is possible to recognize whether or not the catheter is tilted in the image. Therefore, the diameter of the predetermined portion of the blood vessel can be measured with reference to the length of the predetermined portion of the catheter when the catheter is not substantially tilted, and the blood vessel diameter can be measured with high accuracy.

The blood vessel is a coronary artery or a cerebral blood vessel of the heart. The catheter of the present invention is useful when accurate measurement of the diameter of a blood vessel is required although the blood vessel is relatively thin.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. 1 (a)-
(C) is a partial perspective view of the angiographic catheter 5 of the present invention.

In the catheter 5 of the present invention, a contrast agent is injected into a blood vessel, X-ray photography is performed, an image recorded on a cine film or the like is captured as a digital image, and the contour of a predetermined portion of the blood vessel in this image is captured. Is a catheter that can be used in a system that automatically extracts the blood vessel diameter and automatically measures the blood vessel diameter based on the outer diameter or a part of the length of the catheter 5.

As shown in FIGS. 1 (a) to 1 (c), the catheter 5 of the present invention displays the outer diameter of the catheter 5 or the length of a part of the catheter 5 near the tip of the catheter 5. The index 6 is provided.

The index 6 functions as an outer diameter display index for displaying the outer diameter of the catheter 5 in the image displayed together with the blood vessel, and also displays a part of the length of the catheter 5 in the image. It also functions as a length display index for this purpose, and is provided with a portion which serves as a tilt visual recognition index for making the tilt of the catheter 5 visible in the image.

In the example shown in FIGS. 1 (a) to 1 (c), a pair of platinum rings 6a, 6b are attached on the outer peripheral surface of the catheter 5 at a predetermined interval, and the platinum rings 6a, 6 are attached.
The outer diameter of the catheter 5 and the length of a part of the catheter 5 are displayed depending on the length of b, the position of the gap between the platinum rings 6a and 6b, and the like. That is, the platinum rings 6a, 6
b and the gap between them are defined by the above-mentioned outer diameter indicating index,
It is made to function as a length display index or a tilt visual recognition index.

More specifically, in the example of FIG. 1 (a), the platinum rings 6a, 6b are made different in length so that the gap between the platinum rings 6a, 6b is arranged downward, and in the example of FIG. 1 (b), platinum is used. The lengths of the rings 6a and 6b are made different, and the gap between the platinum rings 6a and 6b is arranged upward.
In the example of (c), the platinum rings 6a and 6b have the same length, and the gap between the platinum rings 6a and 6b is arranged at the center. Depending on the position of the gap, the outer diameter of the catheter 5 and the length of a part of the catheter 5 are determined. Is displayed.

Incidentally, 4F in FIGS. 1 (a) to 1 (c),
5F and 6F show the outer diameter dimension of the catheter 5, and FIG.
The outer diameter dimension of the 4F (French) catheter 5 in FIG. 1A is about 1.33 mm, and the outer diameter dimension of 5F in FIG.
The outer diameter of the catheter 5 is about 1.67 mm, and the outer diameter of the catheter 5 of 6F in FIG. 1 (c) is about 2.00 mm.

In the above image, platinum rings 6a, 6
Since b is visible, the gap between the platinum rings 6a and 6b can also be visually recognized. By determining the position of this gap, it is possible to determine the outer diameter of the catheter 5 inserted in the blood vessel, the length of a part of the catheter 5, etc. The diameter of the desired portion of the blood vessel can be measured with high accuracy based on the length and the like.

Also, since the catheter 5 has a shape close to a perfect circle at the place where the platinum rings 6a and 6b are attached, the outer diameter dimension of the portion where the platinum rings 6a and 6b are attached is surely initial. The dimensions are displayed in. This can also contribute to highly accurate measurement of the blood vessel diameter.

Further, by properly adjusting the interval between the platinum rings 6a and 6b, it is possible to determine whether or not the catheter 5 is tilted in the above image.

FIG. 2A shows a state where the catheter 5 is tilted, and FIG. 3A shows a state where the catheter 5 is not tilted. Further, FIG. 2B shows what the index 6 looks like in the image when the catheter 5 is tilted, and FIG. 3B shows the index 6 in the image when the catheter 5 is not tilted. Show what 6 looks like.

As shown in FIGS. 2 (b) and 3 (b), when the catheter 5 is tilted, the images of the index 6 overlap, and it seems as if there is no gap between the platinum rings 6a and 6b. It can be seen that when the catheter 5 is not tilted, the gap between the platinum rings 6a and 6b can be visually recognized.

Therefore, it is possible to determine whether or not the catheter 5 is tilted depending on whether or not the gap between the platinum rings 6a and 6b can be visually recognized in the above image.
If you can see the gap between the platinum rings 6a and 6b,
That is, when the catheter 5 is not tilted, the blood vessel diameter of a desired portion can be measured using the length of the predetermined portion of the catheter 5.

Here, since the actual length of the predetermined portion of the catheter 5 can be determined by the position of the gap between the platinum rings 6a and 6b, etc., the length of the predetermined portion of the catheter 5 can be used to determine the desired portion. The blood vessel diameter can be measured with high accuracy.

Next, the shapes of the platinum rings 6a and 6b and the gap between the platinum rings 6a and 6b are shown in FIG.
Will be described in more detail with reference to FIG.

In the example shown in FIGS. 4 and 5, both platinum rings 6a and 6b have a cylindrical shape. However, any shape other than the cylindrical shape can be adopted as long as it can be mounted on the outer peripheral surface of the catheter 5. Also,
As for the material of the index 6, any material other than platinum can be used as long as it can be recognized in the image taken by X-ray.

Further, the main body of the index 6 is constituted by an integral cylinder made of metal, and various engravings of different shapes are provided on the cylindrical main body, and the outer diameter of the catheter 5 and the length of the index 6 are shown on the image. It may be possible to determine.

In the example shown in FIG. 4A, the length L of the index 6 is
1 is, for example, about 3.3 mm, and the platinum ring 6a
Has a length L2 of about 2.0 mm, and the platinum ring 6b has a length L3 of about 1.0 mm. The width W1 of the platinum rings 6a, 6b is, for example, about 1.3 mm.

At this time, the distance D1 between the platinum rings 6a and 6b is set to about 0.3 mm, for example. in this way,
By setting the distance D1 between the platinum rings 6a and 6b to be small, the catheter 5 can be set to a predetermined angle (θ1) / 2.
(For example, from the state where the catheter 5 is not tilted ± 1
When tilted more than 3 degrees), the images of the platinum rings 6a and 6b overlap each other on the image, and the gap between the platinum rings 6a and 6b almost disappears as shown in FIG. 2 (b). Thereby, it is possible to determine that the catheter 5 is tilted on the image.

In the example shown in FIG. 5, the platinum ring 6a has a length L4 of about 2.0 mm, the platinum ring 6b has a length L5 of about 1.0 mm, and the platinum rings 6a and 6b have a width W2. Is about 2.0 mm
Is.

At this time, the distance D2 between the platinum rings 6a and 6b is set to, for example, about 0.3 mm. Thereby,
When the catheter 5 is tilted by a predetermined angle (θ2) / 2 (for example, about ± 9 degrees from the state where the catheter 5 is not tilted), the images of the platinum rings 6a and 6b overlap each other on the above image, and the platinum rings 6a and 6b are overlapped. 2B, the gap will almost disappear as shown in FIG.

Next, the inventor of the present application derived a relational expression among the inclination angle θ / 2 of the catheter 5, the width W of the platinum rings 6a and 6b, and the distance D between the platinum rings 6a and 6b. The result will be described.

When the relationship among the inclination angle θ / 2, the width W, and the interval D was clarified geometrically, the relational expression D = W × tan (θ / 2) was found between them. It turns out that it holds. In this relational expression, the desired tilt angle θ / 2 and
By substituting it with the width W of the platinum rings 6a, 6b, the required distance D between the platinum rings 6a, 6b is obtained, and whether or not the catheter 5 is inclined in any direction over the set inclination angle θ / 2. Can be determined.

In the present invention, a state in which the catheter 5 is tilted by a predetermined angle or more and it is possible to determine that the catheter 5 is tilted by the index 6 of the present invention is referred to as "the catheter 5 is tilted". A state in which the catheter 5 cannot be determined to be tilted by the index 6 of the present invention because it is tilted only within a predetermined angle or not tilted at all is referred to as “a state in which the catheter 5 is not tilted”.

Next, a coronary angiography examination using the catheter 5 of the present invention will be described. First, the catheter 5 is guided from the artery located in the crotch or the like toward the ascending aorta, and the tip portion of the catheter 5 is inserted into the coronary artery located in the sinus of Valsalva. Then, a contrast agent is injected into the catheter 5 from an angio syringe (not shown), and the contrast agent is ejected into the coronary artery from the opening at the tip of the catheter 5. Then, X-ray imaging is performed while injecting a contrast agent into the blood vessel from the tip portion of the catheter 5.

An image captured by this X-ray photography and recorded on a cine film or the like is taken in as a digital image,
The contour of a predetermined portion of the blood vessel in this image is automatically extracted. At this time, since the index 6 according to the present invention can be visually recognized in the image, the size of the catheter 5 such as the outer diameter of the catheter 5 projected in the image and the length of a predetermined portion of the catheter 5 can be discriminated. it can. Then, an accurate size of the catheter 5 can be input, and the blood vessel diameter can be automatically measured with high accuracy based on this value.

In the above embodiment, the case of using the catheter 5 of the present invention for cardiovascular imaging has been described, but it can also be used for angiography of other organs. In particular, the present invention is useful when it is required to measure the diameter of a relatively thin blood vessel (for example, about several mm) such as a cerebral blood vessel with high accuracy.

Although the embodiments of the present invention have been described above, it should be considered that the embodiments disclosed this time are exemplifications in all points and not restrictive. The scope of the present invention is shown by the claims, and includes meanings equivalent to the claims and all modifications within the scope.

[Brief description of drawings]

1A to 1C are perspective views showing a structure of a distal end portion of a catheter of the present invention.

FIG. 2 (a) is a perspective view showing a tilted state of the catheter of the present invention, and FIG. 2 (b) shows an index of the present invention displayed on an image when the catheter is photographed in a tilted state. It is a schematic diagram which shows a form example.

FIG. 3 (a) is a side view showing a state in which the catheter of the present invention is not tilted, and FIG. 3 (b) is a side view of the present invention displayed on an image when an image is taken in a state in which the catheter is not tilted. It is a schematic diagram which shows the form example of an index.

FIG. 4 (a) is a side view of an example of the index of the present invention in which the dimensions of each part are also shown, and FIG. 4 (b) is a perspective view of the index of (a).

FIG. 5 (a) is a side view of another example of the index of the present invention in which the dimensions of each part are also shown, and FIG. 5 (b) is a perspective view of the index of (a).

FIG. 6 is a schematic diagram showing the heart, ascending aorta, part of the left coronary artery and part of the right coronary artery.

FIG. 7 is an enlarged view showing a state in which the tip of a catheter is guided near the left coronary artery.

[Explanation of symbols]

1 heart, 2 ascending aorta, 3 left coronary artery, 4 right coronary artery, 5 catheters, 6 indicators, 6a, 6b platinum ring.

Claims (5)

[Claims] 1. A catheter for injecting a contrast medium into a blood vessel and measuring the diameter of the blood vessel, wherein the outer diameter of the catheter is displayed on the outer circumference of the catheter in an image taken together with the blood vessel. A catheter having an index for displaying the outer diameter of the catheter. 2. The outer diameter indicating index is attached to the outer circumference of the catheter with a space, and is made of a material that is less permeable to X-rays than the material of the catheter.
The catheter according to claim 1, further comprising a member, wherein an outer diameter of the catheter is indicated by a position of a gap between the first and second members. 3. A catheter for injecting a contrast medium into a blood vessel to measure the diameter of the blood vessel, wherein a part of the length of the catheter in an image taken with the blood vessel is provided on the outer circumference of the catheter. A catheter comprising: a length display index for displaying; and a tilt visual recognition index for visually recognizing the tilt of the catheter in the image. 4. The first and second indicators for displaying the length are attached to the outer circumference of the catheter with a space therebetween and are made of a material that is less likely to transmit X-rays than the material of the catheter.
The catheter according to claim 3, further comprising a member, wherein the inclination visual indicator includes a gap between the first and second members. 5. The catheter according to claim 1, wherein the blood vessel is a coronary artery or a cerebral blood vessel of the heart.