JP3356827B2 - Ultrasound diagnostic equipment - Google Patents

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 which obtains a tomographic image from a thin tubular organ such as a body cavity or the like by ultrasonic pulse echo and performs ultrasonic diagnosis.

[0002]

2. Description of the Related Art Conventionally, when performing ultrasound diagnosis in a body cavity,
This is performed by scanning with an ultrasonic probe and displaying a linear image and a radial image, which are ultrasonic tomographic images, on a monitor. Conventionally, the linear image and the radial image are individually displayed on a monitor. However, when it is desired to observe a plaque or the like in a blood vessel, it is effective to simultaneously display a linear image and a radial image to form a three-dimensional ultrasonic tomographic image. Therefore,
Conventionally, as shown in FIG. 7, a method has been adopted in which an ultrasonic probe is rotated once and then advanced and retracted, and a number of slice images are captured and processed to display a linear image and a radial image. .

More specifically, one scan captures one to eight radial planes in one scan, displays only the fourth radial image, and sequentially captures the same scanning lines in the one to eight radial planes. 1 linear image with
Project on the screen. These operations are repeated to display a radial image and a linear image simultaneously on one screen, thereby obtaining a three-dimensional ultrasonic tomographic image. Another method for simultaneously displaying a radial image and a linear image is disclosed in
As disclosed in Japanese Patent No. 9439, there is a spiral method in which the probe is moved forward and backward as needed, and the probe is rotated accordingly. In this case, there is no problem with the linear image, but the scanning line of one screen of the radial image is in the range of x in FIG. 4. It had become a sound wave tomographic image.

[0004]

However, in the conventional method described above, in the case of the scanning method as shown in FIG. 7 in which one radial image is taken one by one, the starting point and the end point of the probe tip are not clearly positioned. However, there is a problem that the resolution of the linear image is deteriorated. The drive transmission unit that drives the ultrasonic probe is composed of a coil shaft, and if it rotates in the forward rotation direction, it acts in the direction in which the coil shaft contracts, improving radial and linear follow-up performance. However, if the motor rotates in the opposite direction, the coil shaft is loosened, so that the radial and linear follow-up characteristics are very poor. Therefore, when it is desired to perform scanning while stopping the vibration surface of the ultrasonic vibrator at a certain position by the method of FIG. 7, the vibration surface of the ultrasonic vibrator is set to a desired position due to inertial force due to discontinuous movements of stationary and rotation. An appropriate ultrasonic tomographic image could not be obtained without going to the location.

Next, according to the spiral scanning in which the ultrasonic probe is always rotated by the scanning method as shown in FIG. 8 and the ultrasonic probe constantly moves forward and backward, the followability of the ultrasonic probe is extremely improved, while one radial image is obtained. In this case, since the same plane is not scanned, the start point and the end point become discontinuous, and the ultrasonic tomographic image becomes unsightly.

An object of the present invention is to provide an ultrasonic diagnostic apparatus capable of performing scanning while eliminating discontinuous parts in the construction of a radial image and a linear image. Things.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an ultrasonic probe capable of rotating and reciprocating, a first drive unit for rotating the ultrasonic probe, and reciprocating the ultrasonic probe. In an ultrasonic diagnostic apparatus having a second drive unit and a position detector for detecting a rotational position of an ultrasonic probe, a synchronization signal for each rotation of the ultrasonic probe based on a position detection signal from the position detector A driving unit for controlling the advance / retreat movement of the ultrasonic probe by the second driving unit in synchronization with the ultrasonic probe while continuously rotating the ultrasonic probe; and synchronizing the ultrasonic probe with the synchronization signal. The reciprocating motion is performed intermittently and a radial image is obtained during the successive stop periods of the reciprocating motion.

[0008]

As described above, the ultrasonic probe is rotated by the first drive unit, and the second probe is synchronized with the synchronization signal for each rotation.
The ultrasonic probe is intermittently advanced and retracted by the drive unit of
Since the radial images are obtained during the successive stop periods of the forward and backward movements, the write start position and the write end position in each radial image are always the same, and a good radial image without discontinuous portions can be obtained. When the ultrasonic probe is held on the coil shaft, the coil shaft can be constantly rotated in the direction of contraction, and the followability of advance and retreat can be improved. Does not have any discontinuous portions.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1, 2, 3 and 4 show an embodiment of the present invention, of which FIG. 1 is a sectional view of a driving section. The ultrasonic vibrator 1 is connected to a drive transmission unit 2 formed by a coil shaft,
It is held in the outer cylinder 3. A sealing member 4 and an O-ring 5 are provided inside the outer cylinder 3, and the drive transmission unit 2 is supported so as to be drivable, and a distal end portion of the outer cylinder 3 formed by the sealing member 4 and the inner wall of the outer cylinder 3 is provided. The sound transmission medium 6 is filled. Further, the drive transmission section 2 extends in the direction of the rotation drive section, and is connected to the first rotation drive section 8 via the connection section 7.

[0010] A position detector 9 for detecting a rotational position is connected to the first rotation drive unit 8, and these are held by a first rotation drive unit exterior 10. The first rotary drive unit exterior 10 is connected to the forward / backward drive unit 12 via the forward / backward drive transmission unit 11. The forward / backward drive unit 12 is connected to a second rotary drive unit 13, and the first rotary drive unit exterior 10, the forward / backward drive transmission unit 11, the forward / backward drive unit 12, and the second rotary drive unit 13 are connected to the second rotary drive unit 13. Is held by the exterior 15. The outer cylinder 3 is fixed to the second exterior 15.

FIG. 2 shows a configuration of a control system of the driving section. The control circuit 16 is connected to the switch 17, the position detector 9, and the changeover switch 18. The DC power supply 19 is connected to the first rotation drive unit (DC motor) 8 through the switch 17. Next, a position detector (encoder) 9 connected to the first rotation drive unit 8 outputs position information to the control circuit 16 and is connected to a changeover switch 18. The changeover switch 18 is connected so as to drive the second rotation drive unit (stepping motor) 13 based on the position information.

FIG. 3 shows the timing of each signal in the operation of the drive section. First, when the switch 17 is turned on by the control circuit 16 (b signal), the DC power supply 19
(A signal) is supplied to the first rotation drive section 8 (c
Signal), the first rotation drive unit 8 rotates. In synchronization with this rotation, the phase detector 9 outputs A-phase, B-phase, and Z-phase. In FIG. 3, the e signal and the f signal are the A phase, and the d signal is the Z phase. The Z phase is configured to output one pulse when the A phase outputs three pulses. Note that, in practice, the A phase 25
One pulse of the Z phase is output for six pulses.

As described above, the Z phase of the d signal and the A phase of the e signal are sent to the control circuit 16 so that transmission / reception is performed at the timing of the A phase and a radial image of one screen is constructed at the timing of the Z phase. Let it. Further, the phase A of the position detector 9 (f
Signals and the B phase (g signal) pass through the changeover switch 18 and are input to the second rotation drive unit 13, and the stepping motor is controlled by the A and B phases, which are the j and k signals from the control circuit 16. Is rotated. When the second rotation drive unit 13 rotates in this manner, the forward / backward movement transmitting unit 11 shown in FIG. 1 moves forward / backward to move the ultrasonic transducer 1 forward / backward.

The timing of switching between forward and backward movements is determined by the h signal shown in FIG. 3, and the time of forward and backward movement is determined by the i signal. For example, the switching timing of the h signal is set so that the Z phase of the d signal advances during five pulses, and is inverted when the six pulses arrive. Also, every time the Z phase of the d signal comes, the i signal switches, and i
When the signal is high, the robot moves forward and backward while rotating, and when the signal i is low, only the rotation is performed.

Since the present invention is configured as described above, it is possible to cause the ultrasonic vibrator 1 to rotate, then advance and retreat while rotating, and then perform only rotation. By repeating such a motion, when a linear image is obtained, the resolution is not reduced, and the second rotation drive unit 1
3 can be operated intermittently, and a radial image having a continuous start point and end point can be obtained. That is, the motion of the ultrasonic transducer 1 as shown in FIG. 4 can be realized. The transmission timing from the control circuit 16 is set to be transmitted when the ultrasonic probe is not moving forward and backward.

Incidentally, the drive transmitting section 2 must perform scanning in a state where the portion into which the ultrasonic probe is inserted is greatly curved. In the conventional ultrasonic probe, the rotation of the ultrasonic vibrator does not completely follow the rotation of the rotation drive unit due to such a curvature, and an image deletion may occur. In this regard, in this embodiment, as shown in FIG. 5, the adhesive medium 20 is inserted into the gap between the double wound flexible shafts.
By filling the inner coil, the inner coil and the outer coil are brought into close contact with each other to improve rotation transmission. As the viscous fluid to be used, an elastic adhesive that keeps the elastic substance in a solidified state, a viscous fluid such as pine wood, a gel-like substance having a high viscosity property, or the like may be appropriately selected and used.

FIG. 6 shows a method of applying a viscous fluid of the above elastic substance to the gap between the double flexible shafts. First, coil wires 24 and 25 are pulled out from the inner coil bobbin 22 and the outer coil bobbin 23, respectively, and wound around the rotating core 21 to form a flexible shaft. In this case, after the inner coil wire is wound and before the outer coil wire is wound, the outer coil wire is wound after passing through the viscous fluid tank 26. 26a is a seal, and 27 is a heater for heating the viscous fluid as needed. By doing so, the gap between the double coils can be uniformly and uniformly filled with the viscous fluid.

[0018]

As described above, according to the present invention, while continuously rotating the ultrasonic probe, the ultrasonic probe is intermittently moved forward and backward in synchronization with the synchronization signal for each rotation. Since the radial images are obtained during the successive stop periods of the forward and backward movements, the write start position and the write end position of each radial image can always be the same, and a good radial image without discontinuous portions can be obtained. . In addition, when the ultrasonic probe is held on the coil shaft, the coil shaft can be constantly rotated in the direction in which the coil shaft is narrowed. Therefore, the followability of advance and retreat is improved, and the scanning intervals of the linear scan can be made equal. Therefore, even when a linear image is constructed from a plurality of radial images, discontinuous points do not appear in the linear image, and an appropriate linear image can be constructed. In addition, it is possible to prevent breakage of a lead wire (not shown) passing through the coil shaft.

[Brief description of the drawings]

FIG. 1 is a sectional view of a driving unit according to the present invention.

FIG. 2 is an explanatory diagram of an operation of a driving unit.

FIG. 3 is an explanatory diagram for explaining the timing of each signal in the drive unit.

FIG. 4 is an explanatory diagram showing a scanning method.

FIG. 5 is a partial sectional view of the flexible shaft.

FIG. 6 is a schematic view showing a method for manufacturing a flexible shaft.

FIG. 7 is an explanatory view showing a conventional scanning method.

FIG. 8 is an explanatory diagram showing a conventional scanning method.

[Explanation of symbols]

 Reference Signs List 8 first rotation driving unit 9 position detector 13 second rotation driving unit 16 control circuit 17 switch 18 changeover switch 19 DC power supply

Claims (1)

(57) [Claims] 1. An ultrasonic probe capable of rotating and moving forward and backward, a first driving unit for rotating the ultrasonic probe, a second driving unit for moving the ultrasonic probe forward and backward, and a rotational position of the ultrasonic probe An ultrasonic diagnostic apparatus having a position detector for detecting the position of the ultrasonic probe in synchronization with a synchronization signal for each rotation of the ultrasonic probe based on a position detection signal from the position detector. A driving unit for controlling the forward / backward movement of the ultrasonic probe; while continuously rotating the ultrasonic probe, the ultrasonic probe is intermittently moved forward / backward in synchronization with the synchronization signal to sequentially move forward / backward. An ultrasonic diagnostic apparatus characterized in that a radial image is obtained during the suspension period of the ultrasonic diagnosis.