JPH0595506U - Ultrasound imaging catheter - Google Patents

Abstract

(57) [Abstract] [Purpose] A three-dimensional scanning type intracavity probe, that is, an ultrasonic imaging catheter, that minimizes the hard part near the probe tip and allows a large observation field and depth of observation. I will provide a. [Structure] In an ultrasonic imaging catheter 30 that can be inserted into a body cavity, an outer tube 31 and an inside of the outer tube 31,
A rotating shaft 32 arranged along the longitudinal direction of the outer tube 31,
A plate-shaped holding member 34 attached to the tip portion 32a of the rotary shaft 32 at a predetermined angle with respect to the rotary shaft 32;
A plurality of transducer groups 36 arranged on both sides of the holding member 34,
And 38.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 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]

[Prior Art]

 The ultrasonic diagnostic apparatus is one of the image diagnostic apparatuses that have become very popular in recent years. The subject of diagnosis is almost the whole body of the human body, and many probes (linear probe, convex probe, sector probe, etc.) for observing internal organs from outside the body have been put to practical use. Recently, intracavity probes (transrectal probe, transluminal probe, and transesophageal probe) that allow direct observation of the target organ from inside the body have been developed, enabling more precise observation and diagnosis.

Furthermore, not only two-dimensional images but also body cavity probes for obtaining three-dimensional images have been developed, and some structures have been proposed. As a conventional intracavity probe capable of obtaining a three-dimensional image, there are roughly known three types as shown in FIGS. 9 to 14. In the structure shown in FIG. 9, by rotating the drive shaft 120 in the direction of the arrow A, the vibrator (ultrasonic wave transmitter / receiver) 110 attached to the tip of the drive shaft 120 is rotated around the central axis of the probe 108, and 360 degrees. 10 is performed by performing radial scan 150 at the same time, moving the transducer 110 also in the longitudinal direction of the probe 108 (direction of arrow B), and performing radial scans 151, 152, 153, ... Sequentially. It is intended to obtain an image of the cylindrical three-dimensional area 100 as shown. (JP-A-57-9439, 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 oscillator 110 is rotationally scanned around the center axis of the probe 108 by the rotation of the rotary shaft 120 in the direction of arrow A, and the probe 110 is centered on the support shaft 140 attached to the tip of the rotary shaft 120. Rotational scanning is performed in the direction of arrow C along the longitudinal direction of 108. By these two-direction rotational scanning, a spherical three-dimensional scanning region is formed near the tip of the probe 108 (JP-A-63-115546). In addition to this, as disclosed in, for example, JP-A-1-62130, JP-A-60-14845, JP-A-60-68835, and JP-A-60-119930. It is known that a three-dimensional scanning area is obtained by complex mechanical scanning.

FIG. 13 shows that three-dimensional scanning is realized by combining electronic scanning and mechanical scanning. By rotating the rotary shaft 120 in the direction of the arrow A, the linear array oscillator 200 is rotationally scanned around the central axis of the intracavity probe 108, and as shown in FIG. The three-dimensional scanning region 300 is formed (Japanese Patent Laid-Open No. 56-15733).

[0006]

[Problems to be Solved by the Invention]

 Here, as in the above-mentioned conventional example shown in FIG. 9, the method of performing three-dimensional scanning by moving the radial scanning surface in a direction orthogonal to the scanning surface has some drawbacks. . One of them is that the opening width of the vibrator 110 is limited to the inner diameter of the probe 108 (the opening width of the vibrator 110 that can be set is automatically determined by the inner diameter of the probe 108). Is. In other words, the frequency used according to the diagnostic purpose is also determined by this aperture width, so 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 in the image position. 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 part where the vibrator 110 moves must be hard so that it does not bend, but in order to increase the observation field L, the moving distance of the vibrator 110 It is also necessary to lengthen the length, 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, the method of combining mechanical scans in a complex manner complicates the mechanism for the scans. Therefore, in order to accommodate this complicated mechanism, the diameter of the probe is It tends to be large, making it unsuitable for probes inserted into body cavities. 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 and corresponds to the region of the observation visual field L (corresponding to the opening width of the linear array resonator 200). In principle, the area that is formed is a hard portion. Therefore, considering the insertability into the body cavity, the observation visual field L is considerably limited, and the usefulness of the three-dimensional scanning is impaired. However, the aperture in the azimuth direction that determines the azimuth resolution of the oscillator has the advantage that it is not limited by the outer diameter of the probe. Therefore, it is possible in principle to make 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 a hard portion in the vicinity of a probe tip portion to a necessary minimum length, and It is an object of the present invention to provide a three-dimensional scanning type intracavity probe, that is, an ultrasonic imaging catheter, which enables a large observation depth.

[0009]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems and to achieve the object, an ultrasonic imaging catheter of the present invention is an ultrasonic imaging catheter insertable into a body cavity, comprising an outer tube, an outer tube, and an outer tube. A rotary shaft arranged along the longitudinal direction of the pipe, a plate-shaped holding member attached to the tip of the rotary shaft at a predetermined angle to the rotary shaft, and the holding member. It is characterized by comprising a plurality of transducer groups arranged on both sides of the.

[0010]

[Action]

 As described above, since the ultrasonic imaging catheter according to the present invention is configured, electronic scanning type transducer groups are provided on both sides of the plate-shaped holding member attached at a predetermined angle with respect to the rotation axis. By providing this, it is possible to perform stereoscopic scanning with an extremely wide area by simply rotating the rotation axis, and thus, it is possible to perform stereoscopic image observation of living tissue near the insertion tip of the outer tube. An imaging catheter can be realized. Also, since the transducer group is attached to the rotation axis via the holding member, it is possible to scan a wide range of three-dimensional objects, but the hard portion of the tip of the outer tube is the minimum necessary. The length is suppressed, and it is possible to prevent the insertion property into the body cavity from being impaired.

[0011]

【Example】

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, before describing the ultrasonic imaging catheter of the embodiment, a comparative example with respect to the embodiment Will be described. Three-dimensional scanning is performed with a simple scanning mechanism, the observation field of view and depth are made large, the aperture of the transducer is not limited to the probe diameter, and the rigid part of the probe insertion tip is made as short as possible. As a system, as shown in FIG. 1, in the conventional example shown in FIG. 13, a convex type array oscillator 12 is provided instead of the linear array oscillator 200, and an arrow of the rotary shaft 14 is provided. A method of performing vertical scanning by rotation in the A direction can be considered first (in this case, a field of view SA that is wider than the field of view L obtained by a linear transducer of the same length can be obtained. The observation field is wide even if the length is the same). In this method, the area indicated by reference numeral 400 in FIG. 2 is stereoscopically scanned. However, in this method, when it is desired to further expand the observation field, particularly the field of view SA near the probe, it is necessary to dispose a longer convex type array transducer 20, as shown in FIG. As a result, the length L ₁ 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 of increasing the convex angle (curvature) as shown in FIG. 4 is also conceivable. However, as the probe diameter becomes larger, the wide-angle convex-type array oscillator 22 has a scanning density at a distant position. Since it is coarse, 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. And is rotationally driven by a drive device (not shown). A plate-shaped holding member 34 is attached to the tip portion 32a of the rotating shaft 32 in a state of being inclined by an angle α. Convex array transducers 36 and 38 are attached to the front surface and the back surface of the holding member 34, respectively.

With such array transducers 36 and 38, scanning is performed in a range inclined with respect to the rotation axis 32, as indicated by C ₁ and C ₂ in FIG. 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 the convex scanning in the range indicated by C ₃ and C ₄ . In this way, when the rotary shaft 32 is rotated 360 ° in the direction of the arrow A, three-dimensional scanning is carried out. However, as shown in FIG. _C is seen to theoretically wider obtained from field S _a when the convex type array transducer 12 is not inclined as shown in FIG. 1 is attached. It can also be seen that the visual field width L _C in the area away from the probe is also expanded. The larger the tilt angle α, the wider the observation field of view. (Other Embodiment) FIG. 8A is a diagram schematically showing the configuration of another embodiment of the present invention. In order to make the comparison with the embodiment shown in FIG. 5 easier to understand, FIG. 8B also shows a configuration diagram of the embodiment. In this other embodiment, the holding member 34 is not directly attached to the tip portion 32a of the rotary shaft 32 as shown in FIG. 8B, but is further extended from the tip portion 32a and is inclined from the inclined portion 32b. It is installed so that it is inclined in the opposite direction.

In the configuration of the embodiment shown in FIG. 8B, the convex array transducers 36 and 38 rotate about the tip portion 32 a of the rotary shaft 32, and therefore the convex array transducer 36. , 38 has a distance R (the tip 34a of the holding member 34). _B It will rotate within the range (on the circumference) with the diameter as. On the other hand, in the configuration of the other embodiment shown in FIG. 8B, the tips of the convex type array transducers 36, 38 (tips 34a of the holding member 34) are imaginary when the rotary shaft 32 is extended. Since the rotation rotates about the center 40, 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 (tip portions 34a of the holding member 34) are The distance R is 1/2 that in the case of one embodiment_A It will rotate in a range (on the circumference) with the diameter as. In other words, the other embodiment is superior to the one embodiment in that the diameter of the outer tube 31 can be reduced even in the same three-dimensional scanning region.

It should be noted that the present invention can be applied to modifications and variations of the above embodiments without departing from the spirit of the present invention. For example, in the above embodiment, the case where the convex type array wave oscillator is used has been described. However, a linear type array oscillator or a sector scanning type oscillator is used instead of the convex type array oscillator. It is also possible. 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.・ The characteristics tend to be the same as those of the probe.

[0016]

As described above, according to the present invention, the electronic scanning type vibrator group is provided on both surfaces of the plate-shaped holding member attached at a predetermined angle with respect to the rotation axis. Therefore, by simply rotating the rotation axis, it is possible to perform stereoscopic scanning with an extremely wide area, and as a result, ultrasonic waves that enable stereoscopic image observation of living tissue near the insertion tip of the outer tube. Imaging catheters can be realized. In addition, since the transducer group is attached to the rotation axis via the holding member, it is possible to scan in a wide range of three-dimensional areas, but the rigid portion of the outer tube tip is the minimum necessary. It can be prevented from being impaired in the insertability into the body cavity because the length of the body is suppressed.

[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 of one embodiment.

FIG. 4 is a diagram showing a comparative example with the ultrasonic imaging catheter of one 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 rotating shaft is rotated in the ultrasonic imaging catheter of FIG.

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

[Scope of utility model registration request] 1. An ultrasonic imaging catheter insertable into a body cavity, comprising: an outer tube, a rotating shaft disposed inside the outer tube along a 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 rotating shaft, and a plurality of transducer groups arranged on both surfaces of the holding member. Ultrasound imaging catheter.