JPS6014842A - Method and apparatus for detecting spine abnormality - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a column abnormality detection method and apparatus.

ing.

Conventionally, as a method for detecting this, a moire method has been used in which moire fringes are formed on the entire back and it is determined whether the distribution of moire fringes is balanced between the left and right backs of the pillar. This method has the disadvantage that moire fringes cause examiner fatigue when making judgments, making it difficult to analyze the data. Another detection method is to directly determine the abnormality of the pillar by taking x-mography, but this method is customarily used only for detailed examinations because radiation exposure is a problem.

SUMMARY OF THE INVENTION In view of the above points, it is an object of the present invention to provide a method and apparatus for detecting an abnormality in a pillar, which can easily detect a foreign state in a pillar.

In order to achieve this objective, in the present invention, at least one virtual image is placed on the left @l] and right back of the subject along the line.
The present invention is characterized in that the original beam is irradiated diagonally one by one, and the difference in interval between the light beam irradiation position and the virtual position is detected. Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of the device according to the invention.

The beam 11 emitted from the laser 1 is expanded perpendicularly to the plane of the paper by a cylindrical lens 5 whose generatrix direction lies within the plane of the paper, and is directed to the left 1 of the examiner S! Irradiates the surface at an irradiation angle θ. On the other hand, the beam 12 emitted from the laser 2 is spread in a direction perpendicular to the plane of the paper by a cylindrical lens 4 whose generatrix direction lies within the plane of the paper, and is irradiated onto the right back surface of the examiner S at an irradiation angle O.

Regarding the pillar of subject S, left m! The slit beams 5 and 6 irradiated to I and the right side are captured by a video camera 9 through a lens 8 and displayed on a monitor 13 K 5', 6', and the video signal from the video camera 9 is sent to a signal processor 10. It will be processed properly.

Here, it is known that if the subject has a columnar abnormality such as columnar osteopathy, the unevenness of the back becomes asymmetrical, and the present invention uses this. That is, using the point where the beam 11 emitted from the laser 1 and the beam 12 emitted from the laser 2 intersect in FIG. When the coordinates of the position P2 where the beam 12 illuminates the back surface are (X2, 72), the following equation holds true.

71=X1/lanθ y2=x2//lanθ Column abnormality is determined by using the virtual center line of the subject in the column direction, that is, the X direction, and the light beam irradiation position along the direction perpendicular to the X direction and the virtual It can be determined by detecting the interval difference 'lX+ l -IX2 +, but clinically it is △7
It is desirable to detect the virtual value of =7+-7z along the column line direction and judge whether this is within the permissible range.

If you just irradiate one beam diagonally to your back, you can determine whether or not you have scoliosis even if the curve in the front-back direction (depth direction) of the column is 9. Although it is not possible to do this, in Hondari J, at least one beam is irradiated diagonally on the left [11] and right side of the back to treat postural abnormalities such as postal kyphosis! Dorsal column abnormalities can be determined from the asymmetry of the unevenness on the left and right dorsal surfaces. It should be noted that setting of the virtual line location can be done by various known means.

FIG. 2 shows an image when a filter 7 that transmits only the wavelength of the irradiated laser beam is suppressed in the same way as the optical path.

Only the irradiated beam can be clearly detected by the filter 7.

FIG. 6 shows the left and right light irradiation positions on the scanning line of Nth, u+m@th, 11+2 m@th, . . . , and FIG. 4 shows a video signal.

In FIG. 4, a is the Nth video signal and b is the IJ10mth video signal. From each horizontal synchronization signal, the time at the position Ma irradiated by the light beam of left τ11], tNi+t(lJ0m)1・
Also, the time tN2 to the position irradiated by the right light beam
+t(N+m)2 is measured and an abnormality is detected based on the distribution of the difference between the two intervals.

When detecting a signal, since a high level signal is obtained at sl, 61, an appropriate threshold can be easily set. Note that the filter 7 is useful for removing noise in signal processing.

5 and 6 show the distribution of the distance difference C between the left and right light irradiation positions and the virtual column line in the virtual company line direction (two directions). .

As shown in FIG. 5, if there is no column abnormality, the spacing difference C is within the permissible range, but if there is a column abnormality, as shown in FIG. 6, it will exceed the permissible range.

FIG. 7 shows an embodiment of a block diagram of the signal processor of FIG. 1.

The video signal VB is input to the video amplifier 14 and is binarized by the digitalization comparator 15 as the H1 output at a level higher than the threshold set by the voltage setter 18.

19 is input to a blank time ¥621 that counts the number of clocks for the time tN1 from the horizontal synchronizing signal HD to the left beam irradiation position. Data bus control circuit 21 functions as a selector switch to memory 22 and CPU 29.

On the other hand, 2o is a counter that counts the number of clocks during the time tM2 from the horizontal synchronization signal HD to the right beam irradiation position, and its output is input to the data bus control circuit 25.
j-ru.

The two counters 1.20 are reset at the timing of reset 1 in FIG. r 21.25 Read through. This operation is performed sequentially for each scanning line.

Addresses in the memory are generated by the scanning line number counter and the address signals θ to h in FIG.
I'll give it to you through.

The CPU 29 is normally unrelated to the circuit described above, but when the measurement start switch 3o is pressed once, the CPU 29 allows the memory circuits 22 and 26 to receive data of the video signal VS only for the measurement time of one vertical scanning period. , the data bus control circuits 21 and 25 calculate the signal interval difference sequentially.
, the chip select control circuit 25.27 sends a control signal to the address bus control circuit, sets the memory circuit 22.26 to READ mode, stops receiving data of the video signal, and stores the contents as vD2 in FIG. 9C. Read at the timing of Then, the contents are processed and printed out as data of the subject S by the printer 61.

After completing one cycle of operation, the operation of measuring data from the video signal is started again. Thereafter, the switch 60 is pressed as appropriate to perform measurements. FIG. 8a shows a video signal focused on the horizontal scanning period, and b shows the output signal 32 of the binarization comparator 15.
shows.

Further, C indicates a horizontal synchronizing signal HD, and d indicates a timing signal 33 consisting of a pulse generated at a timing slightly delayed from the horizontal synchronizing signal HD. In Fig. 9, a is a video signal focusing on one vertical scanning period, and b is a horizontal synchronizing signal HD%.
C indicates a vertical synchronizing signal VD, d indicates a signal vD' generated at the falling edge timing of the vertical synchronizing signal vD, and e-h indicates an address signal 4.

The present invention has been described in detail above, but in the present invention, the incident angles of the light beams irradiated to the left and right sides of the subject's back surface do not have to be equal to each other, and the virtual distances from the column line are equal. It is not necessary to irradiate 1a to some extent. If these are stored in advance as offset amounts, it is also possible to use a parallel line separated by a predetermined interval from the correctable line in a later calculation process.

Note that the light beams to be irradiated on the left and right sides of the subject's back need not be one each, but several bales, for example, two on each side, on the left side,
The right back surface may be irradiated with two parallel slit beams.

Further, the light beam may be a scanning beam that scans in synchronization with a video signal instead of a stationary slit beam.

Furthermore, instead of the video camera 9, an image sensor such as a CO
D may be provided to detect the coordinates X1 and X2 using the CCD output, and finally calculate clinically useful Δy.

At this time, as shown in FIG. 10(A), the CCD 3 on the image plane
4 can be mechanically moved by the motor 35 in two directions, which are the company line directions. Figure 10 (
B) shows a view seen from the rear direction.

Furthermore, as shown in FIGS. 11(A) and 11(B), a mirror 36 is provided between the lens 8 and the image plane, and by rotating the mirror, it is possible to detect the object corresponding to the light receiving area of the one-dimensional COD. The measurement may be performed by moving the slit area. Note that it is clear that COD may be a secondary element. In addition to a laser, a light emitting diode or any other light source can be used as the light source.

As described above, according to the present invention, it is possible to relatively easily and almost in real time change the curvature in the left and right directions of the pillar.In standard scanning video signal processing, the speed is fast, so ink interface to the microcomputer was conventionally troublesome. If a method is adopted in which data is first stored in memory using hardware and the result is processed by a microcomputer, as in the embodiment of the present invention shown in FIG. 7, the ink face can be easily created.

[Brief explanation of the drawing]

Figure 1 is a diagram of an embodiment of the device according to the present invention, Figure 2 is a diagram showing an image when a wavelength-selective filter is inserted into the optical path, and Figure 3 is a diagram showing left and right lights on scanning lines at arbitrary intervals. Figure 4 is a diagram showing the irradiation position, Figure 4 is a diagram of the Nth and N-1-mth video signals, and Figures 5 and 6 are diagrams showing the distribution of interval differences when there is no column abnormality and when there is, respectively. -j- and Fig. 7 are diagrams of an embodiment of the block diagram of the signal processor, Fig. 8 and Fig. 9 are explanatory diagrams of timing signals focused on the horizontal and vertical scanning periods, respectively, and Fig. 10 (A )(B)? FIGS. 11(A) and 11(B) are diagrams of an embodiment using an image sensor. In the figure, S... Subject 1.2... Laser 6.4... Cylindrical lens 5.6... Slit beam 7... Wavelength selection filter 8... Lens 9... Video camera 10...Signal processor 13...Monitor 54... CCD 35...Motor 36...Mirror - Applicant: Canon Co., Ltd.

Claims (1)

[Claims] 1. At least one light beam is obliquely irradiated on each of the left and right rear surfaces of the subject along a virtual line, and a difference in interval between the light beam irradiation position and the virtual line is detected. and the pillar abnormality detection method. 2. A column abnormality detection method according to claim 1, wherein a distance difference in the depth direction of the subject is calculated based on the distance difference. (v) means for diagonally irradiating at least one light beam on each of the left and right rear surfaces of the subject along the line, position detection means for detecting the light beam irradiation position, and changing the detection position of the virtual along the line; A pillar abnormality detection device characterized by having a position changing means. 4 Pillar abnormality detection according to claim 3 in which the light beam is irradiated on the left and right rear surfaces at equal angles 5 Claim 6 or The pillar abnormality detection device described in Section 4. 6. The pillar abnormality detection device according to claim 5, wherein the position detecting means is a video camera, and the position changing means is a video signal. 1. The pillar abnormality detecting device according to claim 3, wherein the position detecting means is an image sensor. 8. The pillar abnormality detecting device according to claim 3, further comprising a filter for selecting a light beam irradiated within the optical path to the position detecting means. 2. The column abnormality detection device according to claim 3, further comprising means for calculating the amount of deviation of the light beam in the depth direction of the subject from the irradiation position detected by the position detecting means. 10. The pillar abnormality detection device according to claim 6, wherein the light beam is a slit beam. 11. The pillar abnormality detection device according to claim 3, wherein the light beam is a scanning beam. 8. The column abnormality detection apparatus according to claim 7, wherein said position changing means is means for mechanically or optically changing the relative positional relationship between the subject and the image sensor.