JPH04132543A - Method and apparatus for detecting position of internal bone - Google Patents

Abstract

PURPOSE:To facilitate the detection of the position of an internal bone by arranging an ultrasonic transmitter/receiver to receive a reflected signal after transmission from two transducers, a coordinate converter to convert a signal received into a signal of the length of a bone and a display device to synthesize and display the signal converted in coordinate. CONSTITUTION:Ultrasonic transmitter/receivers 41 and 42 transmit ultrasonic waves alternately so as not to cause mutual interference therebetween. As signals obtained with the ultrasonic transmitter/receivers 41 and 42 is section- wise information on a bone 11, coordinate converters 51 and 52 convert the information into length-wise information. A synthesizer 6 synthesizes signals of the coordinate converters 51 and 52 to be one image signal, which is displayed with a display device 7. In this case, the ultrasonic waves are transmitted alternately from transducers 21 and 22 through water bags 31 and 32 and after signals reflected from the bone 12 and a bone are converted into a length-wise signal, signals from the two transducers are synthesized and displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method and apparatus for detecting the anterior position of the body, which is mainly used in the medical field and which displays the condition of bones in the longitudinal direction.

[Conventional technique Wk] Conventionally, when performing surgery such as artificial joints, it was necessary to cut open the joint area and insert the artificial joint into the bone from this part. In this case, simply inserting the joint did not provide sufficient connectivity. Instead, if left as is, the artificial joint would have to be fixed and wait until the bone tissue joins together.Currently, this artificial joint and The usual method is to screw the bone to the original bone from the side. Cutting through the muscle tissue to reach this screw-fastening site would enlarge the surgical site and delay recovery, so it is unusual to keep this area as small as possible and screw the joint through the musculature around the joint.

In this case, it is necessary to determine the screwing position, and this is usually done while looking at the X-ray image.

[Problems to be Solved by the Invention] However, such conventional methods have the problem of causing health problems because the patient and doctor must perform the surgery while being exposed to X-rays.

[Means for Solving the Problems] In order to solve these problems, the first invention provides a method in which ultrasonic waves transmitted from first and second transducers fixed at opposing positions across a specimen are reflected from bones. The reflected signals coming from the bone are converted into information about the longitudinal direction of the bone, and the converted signals are synthesized and displayed.

The second method involves a device for realizing this method, which includes first and second transducers that are fixed facing each other at a predetermined position with the specimen in between, and a gap between these transducers and the specimen. A water bag that fills the space of
An ultrasonic transceiver device that alternately transmits eight sound waves from two transducers and receives the signals reflected from the bone, and independently converts the signals received from the first and second transducers into signals in the longitudinal direction of the bone. The system is constructed of a coordinate conversion device that performs the conversion, and a display device that synthesizes and displays the coordinate-converted signals.

[Operation] Ultrasonic waves are transmitted alternately from the transducers through the water bladder, and the signals reflected from the bones are converted into longitudinal signals, and the signals from the two transducers are combined and displayed.

[Actual case] FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, 1 is a cross section of a human foot as a specimen, 1 □ is muscle tissue, and 1 □ is bone tissue.

21 and 2□ are transducers fixed at a predetermined distance from the foot 1;
Between 22 and foot 1 is a water bag (filled with water)
3+ and 3□ are placed.

Here, the reason why a water bag was used was to deal with the fact that the size of the specimen is undefined. That is, since the signal from the transducer is used after undergoing N coordinate transformation as will be described later, it is easier to calculate the coordinate transformation if the coordinates are fixed. However, when the transducer is brought into direct contact with the specimen, its coordinates change depending on the size of the specimen, making calculations for coordinate transformation complicated. The transducer was then fixed.

However, if this continues, the ultrasonic waves will be transmitted to the bone through the space between the transducer and the foot, and due to the difference in permittivity between the air and the muscle tissue, interface reflection will occur on the skin of the foot, reducing the amount of light from the bone that can be received by the transducer. The signal becomes weak. For this reason, since the majority of muscle tissue is water, a water bag should be placed between the transducer and the test subject's foot so that the dielectric constant is almost the same as that of the muscle tissue to eliminate unnecessary reflected waves. We are trying to prevent this from occurring.

41 and 42 are ultrasonic transceivers, which transmit ultrasonic waves alternately to avoid mutual interference. 51.5□ is a coordinate conversion device, which transmits and receives ultrasonic waves 1
Since the signal obtained at 141.42 is information in the cross-sectional direction of the bone, it is converted into information in the longitudinal direction.

6 is a synthesizing device that synthesizes the signals of the coordinate transformation devices j5t and 5z into one image signal, and 7 is a display device.

A device configured in this way has a transducer 21.2.
Ultrasonic signals are transmitted alternately from □.

In this case, the reflected wave becomes weaker as it deviates from the line connecting the transducers, so if you want to collect information on that part, you will need to arrange multiple transducers both above and below, but our purpose here is to Since it is only necessary to obtain information regarding the direction from the side, one transducer on the upper side and one transducer on the lower side is sufficient.

The reflected waves from the bone received by the transducer 41.4□ are converted into signals in the longitudinal direction of the bone 1□ by the coordinate conversion devices f5+, 5z, synthesized by the synthesizer 6, and displayed on the display device W7. FIG. 2 is a diagram showing this state, in which the outline of the bone 1□ viewed from the longitudinal direction is drawn, and at the same time, the position signal of the drill 8 inserted into the body is also captured and displayed. The reflected signal from the drill 8 has an intensity equal to or higher than the reflected signal from the bone tissue, and is a signal from the top surface of the drill 8, so the strong signal part in Figure 0, which is perceived as a signal on a crescent moon, is the horizontal line. are shown closely together, and weak areas are shown with more space between the horizontal lines. Also, the symbol indicates the radial direction of the bone.

Figure 3 shows the signal from the upper transducer and the signal from the lower transducer being displayed as they are without being combined; however, it is not necessary to display such a screen in order to obtain an image in the longitudinal direction of the bone. Therefore, it is sufficient to collect data for coordinate transformation in the longitudinal direction in the cross-sectional direction.

[Effects of the Invention] As explained above, the present invention has the advantage that since the position of a tube in the body can be detected by ultrasound, there is no need to use X-training, and treatment can be performed safely.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of longitudinal images of six bones obtained by the device shown in FIG. 1, and FIG. It is a figure showing the cross section of the bone obtained. 1...foot, 11...-muscle tissue, 1.・・・・・・
bones, 2. ．． 22...Transducer, 31.3
2...Water bag, 41 + 42...Ultrasonic transceiver, 51, 52-...Coordinate conversion device, 6...
Synthesizing device, 7...Display device. Patent applicant Nippon Telegraph and Telephone Corporation

Claims (2)

[Claims] (1) Receives the reflected signals of the ultrasonic waves transmitted from the first and second transducers fixed at opposite positions across the specimen and reflected from the bone, and converts each reflected signal into information about the longitudinal direction of the bone. A bone position detection method in the body that converts the signals, synthesizes the converted signals, and displays them. (2) First and second transducers that are fixed facing each other in a predetermined position with the specimen in between, a water bag that fills the space between these transducers and the specimen, and ultrasound waves alternately emitted from the two transducers. an ultrasonic transceiver for transmitting signals to and receiving signals reflected from the bone; and a coordinate conversion device for independently converting the signals received from the first and second transducers into signals in the longitudinal direction of the bone. An intracorporeal bone position detection device comprising a display device that synthesizes and displays coordinate-transformed signals.