JPH04354943A - Ultrasonic diagnostic system - Google Patents

Abstract

PURPOSE:To perform treatment by an ultrasonic dignostic system which diagnoses and treats a disorder such as constriction or closure in a blood vessel using an ultrasonic wave from inside the blood vessel by providing an ultrasonic vibrator for transmitting or receiving ultrasonic waves at the tip of a catheter to display information on depth in front of the ultrasonic vibrator on a CRT with a sector scanning of the ultrasonic vibrator. CONSTITUTION:An ultrasonic vibration 2 provided at the tip of a catheter which can be inserted into a blood vessel 23 is provided and a wire-like shape memory alloy shaft 4 is connected to the ultrasonic vibrator 2. The shape memory alloy shaft 4 performs a twisting motion with an ON-OFF switching of electric energization and heating by a current source 14 to make a sector scanning of the ultrasonic vibrator 2 centered on the shape memory alloy shaft 4. The maximum deflection angle is detected with a position detector and sent to an angle computing section 12 to obtain information on the direction of the ultrasonic vibration 2 and a control signal is given for the driving of the current source 14.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus for diagnosing and treating diseases such as stenosis and occlusion within a blood vessel using ultrasonic waves from inside the blood vessel.

0002

[Prior Art] In recent years, angioplasty surgery, which diagnoses and treats diseases such as stenosis and occlusion in blood vessels using catheters inserted into blood vessels, has become more convenient than bypassing blood vessels through open-heart surgery. Attention has been paid. This method of diagnosing diseases such as stenosis from inside blood vessels is known, for example, from Japanese Patent Application Laid-open No. 63
The configuration described in Japanese Patent No. 3834 is known.

[0003] A conventional endovascular video system will be explained below. FIG. 7 is a block diagram of a catheter portion of a conventional vascular endoscopic video system. In FIG. 7, 31 is a catheter. 32 is an optical fiber port for image transmission;
33 is an optical fiber port for guiding illumination light, and 34 is a transparent liquid injection port for removing blood. 35 is a blood vessel, and 36 is an atheroma that is a blockage or stenosis.

The operation of the vascular endoscopic video system configured as described above will be explained below. First, the catheter 31 is inserted into the blood vessel 35, and the atheroma 3 is inserted into the blood vessel 35.
Move to the 6th neighborhood. When the tip of the catheter 31 reaches the vicinity of the atheroma 36, the illumination light guiding optical fiber port 3
3. Illuminate the affected area. Since the inside of the blood vessel 35 is opaque due to blood, in order to obtain a visual field, a transparent liquid such as physiological saline is injected from the blood removal transparent liquid inlet 34, and intravascular endoscopic scanning is performed through the image transmission optical fiber port 32. Check the status of atheroma 36.

[0005]

However, with the above configuration, the state of the atheroma is scanned by an endoscope, and therefore sufficient information in the depth direction cannot be obtained. Also, several times
Since physiological saline is injected into the blood vessels, there is a problem that a large amount of physiological saline may be injected into the living body.

The present invention solves the above-mentioned problems of the prior art, and aims to provide an ultrasonic diagnostic device that uses ultrasound from inside a blood vessel to display the condition of an atheroma in the depth direction on a CRT and performs treatment. The purpose is

[0007]

[Means for Solving the Problems] In order to solve this object, the present invention provides an ultrasonic transducer for transmitting and receiving ultrasonic waves at the tip of a catheter, and a rotation axis of the fan-shaped motion of this ultrasonic transducer has a shape. By controlling the torsional movement of the shape memory alloy shaft using a memory joint, the ultrasonic transducer is scanned in a fan-shaped manner, and information in the depth direction in front of this ultrasonic transducer is displayed on a CRT to treat the inside of the blood vessel. It has a structure.

[0008]

According to the present invention, with the above-described structure, two-dimensional information in the depth direction of an atheroma can be obtained using an ultrasonic transducer without using a transparent liquid for removing blood such as physiological saline.

[0009]

Embodiments (Embodiment 1) A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an ultrasonic diagnostic apparatus according to a first embodiment of the present invention. In FIG. 1, 1 is a catheter, 2 is an ultrasonic transducer provided at the tip of the catheter 1, 3 is a rotary plate made of an insulator connected to the ultrasonic transducer 2, and 4 is a wire-shaped shape memory alloy. 5 is a stopper for fixing the rotating plate 3 and the shape memory alloy shaft 4; 6 is an insulating member; 7 and 8 are conductors; together with the insulating member 6, they support the shape memory alloy shaft 4; support plates A and B having points for fixing the end points of the memory alloy shaft 4;
9 is a support plate A7 for electrically heating the shape memory alloy shaft 4;
10 is a bias plate spring placed inside the catheter 1, 11 is a position detector A placed inside the catheter, and 12 is a position detector B attached to the rotating plate 3. , 13 is an angle calculation unit connected to the position detectors A11 and B12, 14 is a current source for energizing the shape memory alloy shaft 4, 15 is a control unit for driving and controlling the current source 14, and 16 is an ultrasonic vibrator. 2, a receiving section 17 connected to the ultrasonic transducer 2; 18 a transmitting section connected to the ultrasonic transducer 2;
19 is a scan conversion unit connected to the detection unit 18; 20 is a display unit connected to the scan conversion unit 19; 21 is a membrane that covers the tip of the catheter 1; 22 is a catheter a balloon placed outside of 1;
23 is a blood vessel, and 24 is an atheroma that is a blockage or narrowing within the blood vessel 23.

The operation of the ultrasonic diagnostic apparatus constructed as described above will be explained with reference to FIGS. 1, 2, and 3. First, the catheter 1 is inserted into the blood vessel 23 and moved to the vicinity of the atheroma 24, and the transmitter 17 transfers an ultrasound transmission signal to the ultrasound transducer 2. The ultrasonic transducer 2 converts the transferred ultrasonic transmission signal into an ultrasonic wave and transmits it forward. A portion of the transmitted ultrasonic waves passes through the membrane 21 made of a stretchable thin film, propagates through the blood, and reaches the atheroma 24 . A portion of the ultrasonic wave that has reached the atheroma 24 is reflected and returns to the ultrasonic transducer 2, and a portion thereof is transmitted. The ultrasonic waves propagating within the atheroma 24 are reflected one after another due to the difference in acoustic impedance and return to the ultrasonic transducer 2. The reflected ultrasound is converted into an electrical signal by the ultrasound transducer 2, amplified by the receiver 16, and detected by the detector 18.

Next, the scanning method of the ultrasonic transducer will be explained. FIGS. 2A and 2B show a state in which the current source 14 is off, that is, the shape memory alloy shaft 4 is in a non-energized and stationary state. In this state, the shape memory alloy shaft 4 has already been rotated several degrees or several times in the positive direction together with the rotary plate 3 and is twisted, and has torsional stress in the negative direction. It is held down by a bias plate spring 10 via a plate 3, and the ultrasonic transducer 2 is stationary at the maximum rotation angle in the positive direction. A torsion line is shown in the figure to show the state and degree of twist of the shape memory alloy shaft. This is an expression that a straight line tentatively drawn in the length direction of the shape memory alloy shaft surface without twisting virtually draws a spiral due to twisting.

When a current is applied to the shape memory alloy shaft 4 from the current source 14 and the shape memory alloy shaft 4 is heated by electricity, the shape memory alloy shaft 4 has a contraction force in the axial direction and also untwists in the positive direction, that is, in the negative direction. Generates rotational force. This rotational force in the negative direction becomes larger than the force of the bias plate spring, and rotates the ultrasonic vibrator 2 in the negative direction.

FIGS. 2(c) and 2(d) show a state in which the current source 14 is on, that is, the shape memory alloy shaft 4 is energized, and the ultrasonic transducer 2 is stationary at the maximum rotation angle in the negative direction. There is. When the current source 14 is turned off again, the shape memory alloy shaft 4 is cooled in a non-energized state, the rotational force in the negative direction is weakened, and then twisted in the positive direction by the force of the bias plate spring 10, and eventually as shown in FIG. 2(a). , the state returns to state (b).

As described above, the on-off of the current source 14
By switching , the shape memory alloy shaft 4 is repeatedly heated and cooled, and the ultrasonic transducer 2 can be caused to scan in a sector shape around the shape memory alloy shaft 4 . In FIG. 2, the state in which the ultrasonic transducer 2 reaches the maximum rotation angle is detected by the position detectors A11 and B12, and the information is sent to the angle calculation section 13. Based on the information, the control unit 15 controls the current source 14 to
Control n-off. FIG. 3 is a timing chart of control. When the current source 14 is turned on and the ultrasonic transducer 2 reaches the maximum rotation angle in the negative direction, the position detectors A11 and B12 emit signals as shown in FIG.
), the current source 14 is turned off by the signal. The ultrasonic transducer 2 is pushed by the bias leaf spring and reaches the maximum rotation angle in the positive direction, at which point the position detector again emits a signal, which turns on the current source. (T2
-T1) time corresponds to one fan-shaped scan of the ultrasonic transducer 2. The angle calculation unit 13 divides the interval between T1 and T2 into N parts to obtain direction information of the ultrasound transducer 2 corresponding to ΔT.

Based on the information on the rotation angle of the ultrasonic transducer 2 from the angle calculation section 13, the detection signal of the ultrasound reflected signal from the detection section 18 is converted into a standard television signal by the scan conversion section 19, and then converted into a standard television signal. The image is displayed on the display unit 20 as a dimensional ultrasound tomographic image.

Next, referring to the ultrasonic tomographic image, the catheter 1 is moved to the narrowed part of the atheroma 24 and the balloon 22 is inflated to perform blood vessel formation and improve the blood flow state.

(Embodiment 2) A second embodiment of the present invention will be described below with reference to FIGS. 4, 5, and 6.

FIG. 4 is a block diagram of an ultrasonic diagnostic apparatus according to a second embodiment of the present invention. The difference from the first embodiment is that the bias plate spring 10 is not used, and the stopper 45 is made of a conductor, and the current-carrying lead wire 9 is connected to the stopper 45 as well. Further, the current source 14 is of two types: current source A for supplying current to a portion of the shape memory alloy shaft 4 above the stopper 45, and current source B for supplying current to a portion below the stopper 45. ing. In addition, the shape memory alloy shaft 4 has already been twisted in one direction of the shaft rotation direction, and the support plates A7 and B8
is fixed at both ends.

The scanning method of the ultrasonic transducer in the above configuration will be explained. Figures 5(a) and (b) show current sources A and B.
Both are in an off state, that is, the shape memory alloy shaft 4 is in a stationary state with no current applied. In this state, the portion of the shape memory alloy shaft 4 above the stopper 45 is already attached to the support plate A7.
It is installed in a state where it is twisted several degrees or several rotations in the positive direction as it goes from the support plate B8 to the stopper 45, and conversely, the portion of the shape memory alloy shaft 4 below the stopper 45 has already been twisted from the support plate B8 to the stopper 45. It is installed in a state where it is twisted several degrees or several turns in the negative direction as it moves towards the end. The torsional stress in the negative direction in the upper part of the shape memory alloy shaft 4 and the torsional stress in the positive direction in the lower part are balanced, so that the ultrasonic transducer 2 remains stationary. Here, if only the current source A is driven and only the upper part of the shape memory alloy shaft 4 is heated with electricity,
The upper part of the shape memory alloy shaft 4 generates a rotational force in the direction that eliminates twisting, that is, in the negative direction, and rotates the ultrasonic vibrator 2 in the negative direction while further increasing the torsion in the negative direction of the lower part. FIGS. 5(c) and 5(d) are diagrams showing a state in which the current source A is on, the current source B is off, and the ultrasonic transducer 2 has reached the maximum rotation angle in the negative direction and is stationary. Next, when the current source A is turned off and the current source B is turned on, only the lower part of the shape memory alloy shaft 4 is energized and heated.
This time, the direction in which the lower part of the shape memory alloy shaft 4 eliminates twisting,
That is, a rotational force in the positive direction is generated, and the ultrasonic transducer 2 is rotated in the positive direction while increasing the twisting of the upper portion in the positive direction.

FIGS. 5(e) and 5(f) show that current source A is off,
FIG. 6 is a diagram showing a state in which the ultrasonic transducer 2 reaches the maximum rotation angle in the positive direction and remains stationary when the current source B is on.

As described above, by switching the current sources A and B and alternately and appropriately heating and cooling the upper and lower parts of the shape memory alloy shaft 4, the ultrasonic transducer 2 is shaped. Fan-shaped scanning can be performed around the memory alloy axis 4. Figures 5(c), (d) and (e), (f
), the state in which the ultrasonic transducer 2 reaches the maximum positive and negative rotation angles is detected by position detectors A11 and B12, and this detection signal is used to control current source A and current source B according to the control timing shown in FIG. By performing on-off control, the fan-shaped scan of the ultrasonic transducer 2 can be repeated appropriately.

As described above, in the second embodiment, the shape memory alloy shaft is twisted in advance and attached to the support plate, and the current-carrying lead wire is connected to the stopper 5.
The bias leaf spring used in the embodiment becomes unnecessary.

[0024]

As described above, the present invention provides a catheter that can be inserted into a blood vessel, an ultrasonic transducer contained in the tip of the catheter, a rotary plate connected to the rear of the ultrasonic transducer, and a catheter that can be inserted into a blood vessel. a wire-shaped shape memory alloy shaft that forms a central axis of rotational movement of the rotary plate; a drive control unit that controls torsional movement of the shape memory alloy wire; and a drive control unit disposed within the catheter to detect the direction of the ultrasonic transducer. a position detector connected to the position detector, an angle calculating section connected to the position detector, a transmitting section and a receiving section connected to the ultrasonic transducer, a detecting section connected to the receiving section, and the detecting section By providing a scan conversion unit connected to the scan conversion unit and a display unit connected to the scan conversion unit, the ultrasonic transducer inside the catheter can be scanned in a fan-shaped manner with a simple configuration, and the ultrasonic wave in front of the intravascular catheter can be Diagnostic images can be displayed to diagnose diseases such as stenosis and occlusion in blood vessels, and at the same time, it is possible to realize excellent diagnosis and treatment that can easily and quickly perform angioplasty surgery using a balloon.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of an ultrasonic diagnostic apparatus according to a first embodiment of the present invention.

FIG. 2: (a) A front view showing the fan-shaped motion of the ultrasonic transducer in the positive direction in the main part of the device; (b) A side view showing the fan-shaped motion in the positive direction of the ultrasonic transducer in the main part of the device; Front view showing the fan-shaped movement of the ultrasonic transducer in the negative direction in the main part of the device (d) Side view showing the fan-shaped movement in the negative direction of the ultrasonic transducer in the main part of the device

[Figure 3] Control timing diagram for main parts of the device

[Figure 4
] External perspective view of an ultrasonic diagnostic apparatus according to a second embodiment of the present invention

FIG. 5: (a) A front view showing the torsional setting of the shape memory alloy shaft in the main part of the device; (b) A side view showing the torsion setting of the shape memory alloy shaft in the main part of the device; (c) of the device. (d) A side view showing the ultrasonic transducer in the main part of the device in a positive direction fan-shaped motion. (e) Ultrasonic transducer in the main part of the device in the minus direction. Front view showing fan-shaped movement in the direction (f) Side view showing the fan-shaped movement in the negative direction of the ultrasonic transducer in the main part of the device

[Figure 6] Control timing diagram for main parts of the device

[Figure 7
] Enlarged view of the tip of a conventional vascular endoscopic video system

[Explanation of symbols]

1 Catheter 2 Ultrasonic transducer 3 Rotating plate 4 Shape memory alloy shaft 5 Stopper 6 Insulating material 7 Support plate A 8 Support plate B 9 Energizing lead wire 10 Bias plate spring 11 Position detector A 12 Position detector B 13 Angle calculation section 14 Current source 15 Control section 16 Receiving section 17 Transmission section 18 Detection section 19 Scan conversion section 20 Display section 21 Membrane 22 Balloon 23 Blood vessels 24 Atheroma 31 Catheter 32 Optical fiber port for image transmission 33 Optical fiber port for illumination light guidance 34 Transparent liquid inlet for blood removal 35 Blood vessels 36 Atheroma 45 Stopper

Claims (2)

[Claims] 1. A catheter that can be inserted into a blood vessel, an ultrasonic transducer contained in the distal end of the catheter, a rotary plate connected to the rear of the ultrasonic transducer, and a rotational movement of the rotary plate. A wire-shaped shape memory alloy shaft forming a central axis, a stopper that fixes the rotating plate and the shape memory alloy shaft, and a support plate that fixes both end points of the shape memory alloy shaft and maintains the tension of the shape memory alloy shaft. a bias leaf spring that twists the shape memory alloy shaft together with a rotary plate in one direction of the shaft rotation direction and maintains the twist; and a bias plate spring that holds the twist with electricity; and a shape memory effect that causes the shape memory alloy shaft to twist a current source that rotates the current source in the returning direction; a drive control unit that controls on-off of the current source; a position detector disposed within the catheter that detects the direction of the ultrasound transducer; and a position detector that detects the direction of the ultrasound transducer. an angle calculating section connected to the ultrasonic transducer, a transmitting section and a receiving section connected to the ultrasonic transducer, a detecting section connected to the receiving section, a scan converting section connected to the detecting section, and a scanning converting section connected to the detecting section; An ultrasonic diagnostic apparatus comprising: a display section connected to a scan conversion section; a membrane covering the tip of the catheter; and a balloon attached to the catheter. 2. A wire-shaped shape memory alloy shaft is already twisted in one direction of the shaft rotation direction and fixed to the support plate,
2. The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic transducer is configured to scan in a fan-shaped manner by separately heating the upper and lower parts of the shape memory alloy axis in the length direction without using a bias plate spring. .