JPH0534012B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an ultrasonic diagnostic apparatus that mechanically scans an ultrasonic beam in a fan shape to obtain tomographic images of inside the body.

Conventional configurations and their problems Mechanical sector-scanning ultrasonic diagnostic equipment (hereinafter referred to as mechanical sector) generally has a simpler configuration than electronic ones, so the equipment is also smaller. realizable.

Figure 1a shows a general mechanical sector probe (hereinafter referred to as
It is written as a probe. ), a plan view showing an example of the configuration of
Figure b shows a side view of the rotary head on the drive side. As an example, a case of three vibrators 1a, 1b, and 1c will be shown.

In the figure a, a transducer 1 that transmits and receives ultrasonic waves.
a, 1b, 1c are rotary heads 2 that support them.
from the motor 3 which is attached to and is the driving means,
It is rotated by a power transmission means 4 such as a belt or a pulley, and deflection is performed by simultaneously transmitting and receiving ultrasonic waves using the transducers 1a to 1c. At this time, the rotational position of the rotary head 2 is detected by a detector 11 typified by a rotary encoder or rotary potentiometer via a power transmission means 10 different from the one described above, and is detected by a detector 11 typified by a rotary encoder or rotary potentiometer. , is connected to a main unit (not shown). On the main unit,
Based on the data from the detector 11, the speed and position of the motor 3 are controlled through the signal line 12b, and the transducers 1a to
The deflection angle of the ultrasonic beam from 1c is made precise. Here, as an example, transducers 1a to 1
Since we are considering the case where three c are attached to the rotary head 2, there is one in the acoustic window 7 that transmits and receives ultrasonic waves.
It is necessary to select the number of vibrators 1a. Therefore, when a magnetic field is felt on the end face of the rotating head 2, it turns on.
Reed switches 5a, 5b, and 5c are provided corresponding to each vibrator, and a magnet 6 is arranged on a support base 8 near the end face of the rotary head 2.

FIG. 1b shows a view of the rotating head 2 viewed from the direction of the rotating shaft, and the positional relationship between the vibrator, the reed switch, and the magnet will be explained in more detail.

As shown in the figure, an arc-shaped magnet 6 is provided on the support base 8, and reed switches 5a, 5b, 5c are provided in one-to-one correspondence with each of the three vibrators 1a, 1b, 1c. Furthermore, the support stand 8 is provided so as to be rotatable about the rotation axis of the rotary head 2. 9 is a housing.

The rotary head 2 rotates from A to A', and the reed switch 5a, which approaches the magnet 6, is turned on.
The magnet 6 is set so that the reed switch is turned on between A and A', which are fan-shaped scanning areas. ON
The reed switch 5a in this state enables the corresponding vibrator 1a to transmit and receive data.

The transmission signal is sent from the main unit along with the signal line 12b, coupled to the rotary head 2 via a rotary transformer (not shown), and sent to the vibrator 1a via the reed switch 5a. The received signal reflected within the body reaches the main device from the vibrator 1a through the opposite path. As the rotation further progresses, the reed switch 5a comes off from the magnet 6, and at the same time, the vibrator 1a is no longer within the range of A to A' and is turned OFF.
state. Such a process causes other oscillators 1
b, 1c, and other reed switches 5b, 5
It is also repeated in c. Another example of the transducer switching and signal coupling method with the rotary head is the second
There is a method using the slip ring shown in the figure.

Three vibrators 1a to 1c are provided on the side surface of the rotating head 2 provided in the housing 9, and a slip ring 16 is provided near the end surface of the rotating head 2. It rotates with the same rotation as head 2. The slip ring 16 includes one common electrode 15d and three electrodes provided around the common electrode 15d.
It has brushes 13 and 14 connected to one of the individual electrodes 15a to 15c, a common electrode 15d, and one of the individual electrodes 15a to 15c, and vibrators 1a to 15c.
One electrode of the oscillators 1c is connected to the common electrode 15d of the slip ring 16, and the other electrode of the vibrators 1a to 1c is connected to the individual electrodes 15a to 1 of the slip ring 16.
5c. Rotating head 2
When the slip ring 16 rotates and the electrode 15a comes into contact with the brush 14, the vibrator 1a is now ready for transmission and reception. Vibrator 1a
As the rotation progresses further from the position A and reaches A' through the acoustic window 7, the electrode 15a comes off the brush 14 and the transmission and reception of the vibrator 1a ends. From then on, brush 1
4 moves from electrode 15b to electrode 15c, and vibrator 1
b, the vibrator 1c becomes ready for transmission and reception in sequence.

In either case using the reed switch or slip ring, in order to obtain tomographic images in real time, ten or more tomographic images are required per second, and the rotating head must be rotated at high speed. The wider the fan-shaped scanning area (A to A' in the figure) is, the more ideal it is, but by widening it, the scanning speed per tomographic image increases, and the scanning depth decreases accordingly. is constrained to between 60° and 120°.

The case of diagnosing a subject using the probe configured as described above will be described with reference to FIG. 3.

If you want to simultaneously view organ a inside the subject 21 and organ b outside the fan-shaped field of view as shown in the figure, use the probe 2
It becomes necessary to move 0 or tilt it toward organ b. Since the probe 20 cannot necessarily be moved in the same cross-sectional shape, a problem arises in reproducibility and the organs cannot be said to be on the same cross-section. In addition, recently there has been a demand for a probe with a wider field of view, but this cannot be achieved with the probes mentioned above, so in Fig. 1, the reed switches 5a to 5c are turned on. A method has been devised in which the field of view to be examined is expanded without moving the probe itself by moving the position of the magnet and, in FIG. 2, moving the position of the brush 14.

However, with these methods, the position control of the visual field to be examined is inaccurate and cannot be performed at high speed.

Purpose of the Invention The present invention was made to solve the above-mentioned problems, and the scanning position can be varied freely, accurately, and at high speed, and a wide range of fan-shaped tomographic images can be obtained without moving the probe. The purpose is to provide an ultrasonic diagnostic device.

Structure of the Invention The present invention achieves the above object, and includes at least one vibrator, a rotary body that supports and rotates the vibrator, a drive means that rotationally drives the rotary body in an ultrasonic scanning direction, and a rotary body that supports and rotates the vibrator. An angle detection means for detecting the rotation angle of the rotating body; a rotation control section for controlling the speed of the drive means based on the signal from the angle detection means; and a rotation control section that counts the signals from the angle detection means and starts scanning within the subject. a scan control unit that controls the position and the scan range in the direction of the ultrasonic scanning plane; an input unit that inputs a scan start position according to a desired visual field to be examined at the time of diagnosis and instructs the scan control unit to the value; It is characterized by comprising a transmitting/receiving circuit that causes the transducer to transmit and receive ultrasonic waves based on a signal from a scanning control section, and capable of controlling a scanning start position and a scanning range in the scanning surface direction according to a desired field of view to be examined. The present invention provides an ultrasonic diagnostic device that performs the following steps.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings. FIG. 4 is an overview diagram of an ultrasonic diagnostic apparatus that is an embodiment of the present invention. According to the same figure, vibrator 1
A to 1c are attached to a rotating head 2 and driven by a motor 3 through a rotating shaft 22 by a power transmission means 4 consisting of a pulley, a belt, etc. A detector 23 such as a rotary encoder or a rotary potentiometer is provided on this rotating shaft 22 via another power transmission means 10.
3, the position of the rotary head 2 is detected and its angle is output as data.

Now, if the detector 23 is a rotary encoder,
The output from the detector 23 includes a pulse R generated at every fixed angle and a pulse Z generated at every rotation. Pulses R and Z are from main unit 2
4, R is used by the rotation control circuit 25 as a reference signal for rotation control, and causes the motor 3 to rotate at a constant speed.

The transmission signal that drives the vibrator is sent to the transmission/reception circuit 27
, a control circuit 2 including a scan conversion circuit and a display circuit.
6 control pulses. The transmitting/receiving circuit 27 includes at least three transmitting circuits corresponding to the three vibrators, three receiving circuits, a channel switching circuit controlled by a selection counter 29 described later, a gain control amplifier, and a detection circuit.

Transmission signals generated from the transmission/reception circuit 27 are sent to the transducers 1a to 1c via the probe cable 30 and rotary transformers 32a to 32c in the probe section 31. The received signal is received via the opposite route, and the obtained tomographic image is displayed on the display 34. Pulse Z and pulse R from detector 23 consisting of a rotary encoder
is input to the counter 28 which generates the scan start position pulse Z' based on an instruction from the input means 33. The scanning start position pulse Z' and pulse R from the counter 28 are input to a selection counter 29, which generates a selection signal S for controlling the channel switching circuit of the transmitting/receiving circuit 27.

Next, a method of changing the scanning position will be described using the time chart shown in FIG. The counter 28 is reset by the pulse Z, and the data X of the input means 33
The pulse R is counted based on the pulse R, and at the same time as the count ends, a scan start position pulse Z' is output.

The selection counter 29 is reset by the pulse Z', selects the vibrator 1a, and the transmitter/receiver circuit 27
Transmission and reception are performed only with this vibrator 1a. As the rotating head 2 rotates, the selection counter 29 counts the number of pulses R. For example, the rotary head 2 receives one pulse Z and 300 pulses R per revolution.
If this can be achieved, in a probe using three oscillators, the oscillators will switch once every 100 times.

Therefore, by appropriately selecting the data X to be applied to the input means 33, the scanning starting point can be freely changed, and the visual field to be examined can be changed or expanded.

FIG. 6 shows this state as shown on the display 34 of FIG. In FIG. 3A, the tomographic image 35 on the display is shown on a normal fan-shaped scanning screen, and the organ 36 inside the subject can be moved by =X without moving the probe. In the figure b, the entire tomographic image 35 is moved in accordance with the specified X, and the organ 71 is moved along with the movement in a, but with this method, the positional relationship of the organs can also be grasped as is. This case can be realized by considering the scan conversion circuit and conversion method.

This situation is illustrated for the rotating head part.
It will look like the figure. Data from input means 33 =
When the value is 0, the scanning position is from A to A', and by inputting data=X, the scanning position can be changed from B to B'. Count pulse R 100 times from B to B' and switch transmission/reception to the next vibrator.

Here, as the input means 33, in addition to setting the magnitude of by using a volume or a switch, it is conceivable to directly input numerical values using a keyboard. This input means 33 may be attached to either the probe section 31 or the main body section 24, but it is easier to operate if a switch 37 corresponding to the rotary head 2 is provided on the probe section 31.

In addition to inputting data as numerical values or additions and subtractions, by gradually adding or subtracting values to the main unit 24 each time the rotary head 2 rotates once,
With respect to the plane scanned by the ultrasonic beam transmitted and received by the transducer installed on the rotating body, the test range can be automatically moved to the right and left, so the test field of view can be changed from 71c to 71b as shown in Figure 8. →71a→71
It is possible to search while swinging left and right as in b→71c→71d→71e, and it is possible to obtain an effect similar to that of a wide field of view without reducing the frame rate. In this case, it is sufficient to change the value for each frame, and in addition to continuously moving left and right as described above, 71e → 71d → 71c → 71b →
71a and vice versa.

In addition, as shown in FIG. 9, in order to widen the field of view of the probe 37, ₁ is set as a and ₂ is set as b.
₁ image and ₂ images each time rotating head 2 rotates once.
Images may be displayed alternately. In the diagram, ₁ is 0,
The case where ₂ is set to b is shown. Here ₁ = 0
Let 2 be on the right side, _{and 2} be the position rotated by b from ₁ .

In this case, the normal frame rate can be maintained in the shaded area shown in the figure, and the frame rate is reduced to half in the other areas, but it is still effective for knowing the positional relationships of organs over a wide range.

Effects of the Invention In summary, the present invention includes at least one vibrator, a rotary body that supports and rotates the vibrator, a drive means that rotationally drives the rotary body in an ultrasonic scanning direction, and a rotation angle of the rotary body. a rotation control section that controls the speed of the drive means based on the signal from the angle detection means, and a rotation control section that counts the signal from the angle detection means to determine the scanning start position within the subject and ultrasonic scanning. a scan control section that controls the scan range in the plane direction; an input means that inputs a scan start position according to a desired visual field to be examined at the time of diagnosis and instructs the scan control section to the value thereof; The transducer is equipped with a transmitting/receiving circuit that transmits and receives ultrasonic waves to and from the transducer based on the signal, and the scanning start position and scanning range in the scanning plane direction can be controlled according to the desired field of view, so that the probe can be fixed while the probe is being fixed. Since the scanning start position for the subject can be arbitrarily determined, a wide range of biological information can be obtained.

Furthermore, if the display is movable in accordance with the scan start position, there are advantages such as the ability to widen the narrow field of view by moving the scan start position at high speed.

[Brief explanation of the drawing]

Figure 1a is a plan view showing an example of the configuration of a conventional mechanical sector probe, Figure 1b is a side view of the drive side of the rotary head, and Figure 2a is an example of the configuration of another conventional mechanical sector probe. FIG. 2b is a plan view of FIG. 2a,
Fig. 3 is an explanatory diagram when diagnosing a subject with a conventional probe, Fig. 4 is a plan view of an ultrasonic diagnostic apparatus which is an embodiment of the present invention, and Fig. 5 is a time chart of the above embodiment. FIG. 6 is a diagram explaining how to display a tomographic image according to this embodiment, FIG. 7 is a diagram explaining how to scan the rotating head portion of the above embodiment, and FIGS. FIG. 3 is a diagram illustrating a scanning position control method according to the present invention. 1a, 1b, 1c... Vibrator, 2... Rotating head, 3... Motor, 4, 10... Power transmission means,
7... Acoustic window, 23... Detector, 24... Main unit, 25... Rotation control circuit, 26... Control circuit,
27... Transmission/reception circuit, 28... Counter, 29...
...Selection counter, 31...Probe section, 33...
Input means, 34...Display.

Claims (1)

[Claims] 1 at least one vibrator, a rotary body that supports and rotates the vibrator, a drive means that rotationally drives the rotary body in an ultrasonic scanning direction, and an angle detection means that detects a rotation angle of the rotary body. , a rotation control unit that controls the speed of the drive means based on the signal from the angle detection means, and a rotation control unit that counts the signal from the angle detection means to control a scanning start position within the subject and a scanning range in the direction of the ultrasonic scanning plane. a scan control unit that inputs a scan start position according to a desired visual field to be examined at the time of diagnosis and instructs the scan control unit to the value; An ultrasonic diagnostic device characterized by comprising a transmitting/receiving circuit that transmits and receives ultrasonic waves.