JPH08275947A - Ultrasonic imaging catheter - Google Patents

Abstract

PURPOSE: To provide a three-dimensional scanning type probe for body cavity, that is, an ultrasonic imaging catheter in which a hard part near the head part of the probe is necessarily-minimized and observation field and observation depth are made large. CONSTITUTION: This ultrasonic imaging catheter 30 which can be inserted into a body cavity is provided with an outer tube 31, a rotary shaft 32 which is arranged inside the outer tube 31 along the longitudinal direction of the outer tube 31, a board-shaped supporting member 34 which is attached at a specified angle to the rotary shaft 32 of the head part 32 of the rotary shaft 32, and plural vibrator groups 36, 38 which are arranged on both faces of the supporting member 34.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic imaging catheter to be inserted into a body cavity, and more particularly to improvement of an ultrasonic imaging catheter capable of obtaining a three-dimensional image over a wide area.

[0002]

2. Description of the Related Art An ultrasonic diagnostic apparatus is one of the image diagnostic apparatuses that have become very popular in recent years. The diagnosis target is almost the whole body of the human body, and many probes (linear probe, convex probe, sector probe, etc.) for observing internal organs and the like from outside the body have been put to practical use. In addition, recently, a body cavity probe (transrectal probe, transcavity probe, or transesophageal probe) that allows direct observation of a target organ from inside the body has been developed, which enables more precise observation and diagnosis.

Furthermore, a body cavity probe for obtaining a three-dimensional image as well as a two-dimensional image has been developed, and some structures have been proposed.

As a conventional intracavity probe capable of obtaining a three-dimensional image, three types are roughly known as shown in FIGS. 9 to 14.

In the structure shown in FIG. 9, the drive shaft 120 is rotated in the direction of arrow A, so that the transducer (ultrasonic wave transmitter / receiver) 110 attached to the tip of the probe 10 is rotated.
Rotate around the center axis of 8 and 360 degree radial scan 1
While performing 50, the transducer 110 is also moved in the longitudinal direction of the probe 108 (direction of arrow B) to perform radial scanning 1
By sequentially executing 51, 152, 153, ...
Finally, a cylindrical three-dimensional region 100 as shown in FIG.
To get the image of. (JP-A-57-94
39, JP-A-62-284635). In this method, the radial scanning is not limited to the method of directly rotating the vibrator 110, but may be the method of reflecting by the acoustic mirror 160 as shown in FIG.

FIG. 12 shows a structure in which mechanical scanning is combined in a complex manner to three-dimensionally scan a three-dimensional area. Specifically, the vibrator 110 includes the rotating shaft 12
When the probe 108 is rotated in the direction of the arrow A, the probe is rotated around the central axis of the probe 108, and is rotated in the direction of the arrow C along the longitudinal direction of the probe 108 about the support shaft 140 attached to the tip of the rotary shaft 120. To be scanned. These two
A spherical three-dimensional scanning region is formed near the tip of the probe 108 by rotational scanning in the direction (Japanese Patent Laid-Open No. 63-115).
546). In addition to this, for example, Japanese Patent Application Laid-Open No. 1-6213
No. 0, JP-A-60-14845, JP-A-60
As disclosed in Japanese Patent Application Laid-Open No. -68835, Japanese Patent Application Laid-Open No. 60-119930 and the like, there are known ones in which a three-dimensional scanning region is obtained by complex mechanical scanning.

FIG. 13 shows a combination of electronic scanning and mechanical scanning to realize three-dimensional scanning. By rotating the rotary shaft 120 in the direction of arrow A, the linear
The array transducer 200 is rotationally scanned around the central axis of the probe 108 in the body cavity to form a cylindrical three-dimensional scanning area 300, which is substantially the same as that shown in FIG. 10, as shown in FIG. 56-15733).

[0008]

Here, like the one shown in FIG. 9 among the above-mentioned conventional examples, the method of performing three-dimensional scanning by moving the radial scanning plane in the direction orthogonal to the scanning plane is as follows. It has some drawbacks. One of them is that the opening width of the transducer 110 is limited to the inner diameter of the probe 108 (the opening width of the transducer 110 that can be set is automatically determined by the inner diameter of the probe 108).
It is a point. In other words, the frequency used according to the diagnostic purpose is also determined by this opening width, so that the degree of freedom in design is significantly limited. In particular, in the case of a probe having a small diameter, the aperture width becomes small, so that a high frequency must be used in order to improve the resolution of the image orientation. That is, the small-diameter probe adopting this method has a drawback that the observation depth D becomes extremely shallow. Another drawback is that the outer shell of the probe at the portion where the oscillator 110 moves needs to be hard so as not to bend, but in order to increase the observation field L, the oscillator 11
The moving distance of 0 must also be lengthened, and the hard portion (hard portion) is lengthened accordingly. If the hard portion near the tip of the probe 108 becomes long, the insertability will be significantly impaired when the probe 108 is inserted into a body cavity.

Further, as shown in FIG. 12, in a system in which mechanical scanning is combined in a complex manner, the mechanism for the scanning becomes complicated, so that the diameter of the probe is large in order to accommodate this complicated mechanism. And is not suitable as a probe to be inserted into a body cavity. In particular, it cannot be applied to a probe having a small diameter that can be inserted into a blood vessel.

Further, as shown in FIG. 13, the method of combining the linear electronic scanning and the mechanical scanning is similar to the method shown in FIG. 9 in the region of the observation visual field L (the aperture width of the linear array transducer 200). The area corresponding to (1) is, in principle, a hard portion. Therefore, considering the insertion property into the body cavity, the observation visual field L is considerably limited, and the usefulness of the three-dimensional scanning is impaired. However, the opening in the azimuth direction that determines the azimuth resolution of the vibrator has an advantage that it is not limited by the outer diameter of the probe. Therefore, it is possible in principle to take the observation depth D deep.

Therefore, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to keep the hard portion near the tip of the probe to the minimum necessary length.
In addition, a three-dimensional scanning type intracavity probe, that is, ultrasonic imaging, that allows a large observation field and observation depth.
To provide a catheter.

[0012]

In order to solve the above problems and achieve the object, an ultrasonic imaging catheter of the present invention is an ultrasonic imaging catheter that can be inserted into a body cavity.
In a catheter, an outer tube, a rotating shaft disposed inside the outer tube along the longitudinal direction of the outer tube, and a tip portion of the rotating shaft forming a predetermined angle with respect to the rotating shaft. It is characterized in that it is provided with a plate-shaped holding member attached by means of a plurality of vibrators arranged on both surfaces of the holding member.

[0013]

As described above, since the ultrasonic imaging catheter according to the present invention is constructed, the electronic scanning type vibration is applied to both surfaces of the plate-like holding member attached at a predetermined angle with respect to the rotation axis. By providing a child group,
By simply rotating the rotating shaft, it is possible to perform three-dimensional scanning with an extremely wide area, and as a result, an ultrasonic imaging catheter that allows three-dimensional image observation of living tissue near the insertion tip of the outer tube is provided. ,realizable. Further, since the vibrator group is attached to the rotary shaft through the holding member while being tilted, the rigid portion of the outer tube tip portion can be kept to the minimum necessary though a wide range of three-dimensional scanning is possible. The length is suppressed, and it is possible to prevent impairing the insertability into the body cavity.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. First, before describing an ultrasonic imaging catheter of one embodiment, A comparative example for one embodiment will be described.

The three-dimensional scanning is carried out by a simple scanning mechanism, the observation field of view and the depth are made large, the opening of the vibrator is not limited to the probe diameter, and a hard portion of the insertion tip of the probe can be formed. As shown in FIG. 1, a conceivable type array oscillator 12 may be provided instead of the linear array oscillator 200 in the conventional example shown in FIG. First, a method of performing stereoscopic scanning by rotating in the direction of arrow A can be considered (in this case, a field of view SA wider than the field of view L obtained by a linear transducer of the same length can be obtained. That is, the hard portion indicated by L1. Even if the length is the same, the observation field of view is wide). In this system, the area indicated by reference numeral 400 in FIG. 2 is stereoscopically scanned. However, if it is desired to further expand the observation field of view, particularly the field of view SA near the probe by this method, it is necessary to dispose a longer convex array transducer 20 as shown in FIG. As a result, the length L1 of the hard portion of the tip portion becomes long, which causes a problem that the insertability into the body cavity is deteriorated.

A method in which the convex angle (curvature) is increased as shown in FIG. 4 is also conceivable. However, as the probe diameter becomes larger, the wide-angle convex array transducer 22 has a coarse scanning density in the distance. Therefore, there is a problem that image quality is deteriorated.

The ultrasonic imaging catheter 30 according to the embodiment of the present invention shown in FIG. 5 solves this problem. As shown in FIG. 5, a rotating shaft 32 is rotatably arranged along the longitudinal direction of the outer tube 31 which constitutes the outer shell of the ultrasonic imaging catheter 30. , Is driven to rotate by a drive device (not shown). The tip 32 of the rotary shaft 32
a is a plate-shaped holding member 3 tilted by an angle α.
4 is attached. Convex array transducers 36 and 38 are provided on the front and back surfaces of the holding member 34, respectively.
Is attached.

Then, such array transducers 36, 38
According to the method, as shown by C1 and C2 in FIG.
The scanning is performed in a range inclined with respect to. FIG. 7 shows a state in which the rotary shaft 32 is rotated 180 degrees in the direction of arrow A with respect to the state shown in FIG. In this state, the array transducers 36 and 38 are performing a convex scan in the range indicated by C3 and C4. In this way, when the rotary shaft 32 is rotated 360 ° in the direction of the arrow A, three-dimensional scanning is performed, but as shown in FIG. 5, the observation visual field SC in the vicinity of the outer tube 31 is It can be seen that a wider field of view can be obtained in principle from the field of view SA when the convex type array transducer 12 which is not inclined as shown in FIG. 1 is attached. It can also be seen that the field of view LC in the area away from the probe is also expanded. The larger the tilt angle α, the wider the observation field of view. (Other Embodiments) FIG. 8A is a diagram schematically showing the structure of another embodiment of the present invention. In order to make the comparison with the embodiment shown in FIG. 5 easier to understand, FIG.
The configuration diagram of one embodiment is also shown in FIG. In this other embodiment, the holding member 34 is not directly attached to the tip 32a of the rotary shaft 32 as shown in FIG. 8B, but is further extended from the tip 32a and is inclined from the inclined portion 32b. It is attached so as to incline in the opposite direction.

In the configuration of the embodiment shown in FIG. 8B, since the convex array transducers 36 and 38 rotate about the tip portion 32a of the rotary shaft 32, the convex array transducer 36 is provided. , 38 (the distal end portion 34a of the holding member 34) rotates within a range (on the circumference) having the diameter of the distance RB.

On the other hand, in the configuration of the other embodiment shown in FIG. 8B, the convex array transducer 36,
Since the distal end portion of 38 (the distal end portion 34a of the holding member 34) rotates about the virtual center 40 that extends the rotation shaft 32, if the inclination angle β of the holding member 34 is the same as the inclination angle α of the embodiment. The tip portions of the array transducers 36 and 38 (the tip portion 34a of the holding member 34) rotate within a range (on the circumference) having a diameter RA that is 1/2 the distance RA as compared with the case of one embodiment. Become. That is, in this other embodiment, the outer tube 3 is different from that of the first embodiment even in the same stereoscopic scanning region.
It is more excellent in that the diameter of 1 can be reduced.

The present invention can be applied to a modified or modified version of the above embodiment without departing from the spirit of the invention.

For example, in the above embodiment, the case where the convex type array wave oscillator is used has been described.
Instead of the convex array transducer, it is also possible to use a linear array transducer or a sector scanning transducer. However, it goes without saying that the convex type array transducer has the widest observation field of view. The advantage of three-dimensional scanning with a linear array transducer is that the observation field is narrow, but the scanning density is uniform regardless of the observation depth, which means that the linear probe and convex It has the same tendency as the characteristic difference with the probe.

[0023]

As described above, according to the present invention, by providing the electronic scanning type vibrator group on both surfaces of the plate-like holding member attached at a predetermined angle with respect to the rotation axis, By simply rotating the rotating shaft, it is possible to perform three-dimensional scanning with an extremely wide area, and as a result, an ultrasonic imaging catheter that allows three-dimensional image observation of living tissue near the insertion tip of the outer tube is provided. ,realizable. Further, since the vibrator group is attached to the rotary shaft through the holding member while being tilted, the rigid portion of the outer tube tip portion can be kept to the minimum necessary though a wide range of three-dimensional scanning is possible. The length is suppressed, and it is possible to prevent impairing the insertability into the body cavity.

[0024]

[Brief description of drawings]

FIG. 1 is a diagram showing a comparative example with an ultrasonic imaging catheter according to an embodiment.

FIG. 2 is a diagram showing a scanning range when stereoscopic scanning is performed by the catheter shown in FIG.

FIG. 3 is a diagram showing a comparative example with the ultrasonic imaging catheter according to the embodiment.

FIG. 4 is a diagram showing a comparative example with the ultrasonic imaging catheter according to the embodiment.

FIG. 5 is a diagram showing a configuration of an ultrasonic imaging catheter according to an embodiment.

[Figure 6]

FIG. 7 is a diagram showing a scanning range when the rotation axis is rotated in the ultrasonic imaging catheter of FIG.

FIG. 8 is a diagram comparing the configuration of one embodiment with another embodiment.

[Figure 9]

[Figure 10]

FIG. 11

[Fig. 12]

[Fig. 13]

FIG. 14 is a diagram showing a conventional example.

[Explanation of symbols]

 10 Ultrasonic Imaging Catheter 12 Array Transducer 14 Rotation Axis 20, 22 Array Transducer 30 Ultrasonic Imaging Catheter 31 Outer Tube 32 Rotation Axis 34 Holding Member 36 Array Transducer 38 Array Transducer

Claims (1)

[Claims] 1. An ultrasonic imaging catheter that can be inserted into a body cavity, wherein an outer tube, a rotating shaft disposed inside the outer tube along the longitudinal direction of the outer tube, and a rotating shaft of the rotating shaft. It is characterized in that it comprises a plate-shaped holding member attached to the tip end portion at a predetermined angle with respect to the rotation axis, and a plurality of transducer groups arranged on both surfaces of the holding member. Ultrasound imaging catheter.