JP2000298427A - Medical practice device and method for evaluating medical practice result - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medical practice device which is capable of visually observe and objectively evaluate the result of a practice in real time and a method for evaluating the medical practice. SOLUTION: The medical practice device photographs three targets (targets 44A, 44B and 44C) with two units of image pickup cameras 32A and 32B. VC processes the images photographed by the image pickup cameras and forms the position data of the respective targets. These pieces of the position data are utilized for obtaining the three-dimensional coordinate data of the specific position (cutting appliance 50) made correspondent to the targets. The synthesized images superposing the movement of the specific position (cutting appliance) on the image of the object (tooth) to be practiced in accordance with the three-dimensional image data and the image data of the object (tooth 52) to be practiced is displayed on a display device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical training apparatus for objectively and visually evaluating the results of medical training and a method for evaluating the results of medical training.

[0002]

2. Description of the Related Art Conventionally, as a device for visually evaluating the results of dental training, there is a device proposed in Japanese Patent Application Laid-Open No. 10-97187. In this evaluation device, first, the uncut shape data obtained by measuring the uncut tooth model and the cut tooth model that was actually formed in the uncut tooth model as a model by the teacher were measured. From the difference with the obtained cut shape data, teacher cavity shape data is obtained. Similarly, the target cavity shape data is obtained from the difference between the uncut shape data and the cut shape data obtained by measuring the cut tooth model in which the student actually formed the cavity in the uncut tooth model as a training. . Then, based on the teacher cavity shape data and the target cavity shape data, the teacher cavity shape and the target cavity shape are superimposed on the display screen. The formed target cavity shape is evaluated.

[0003]

However, in this evaluation apparatus, the shape of the target cavity is evaluated on the cut target tooth model in which the cavity is formed, and the process of the cavity formation is observed in real time and objectively evaluated. Can not be evaluated.

[0004] It is an object of the present invention to provide a medical training apparatus and a medical training evaluation method capable of visually observing the results of the training in real time and objectively evaluating the results.

[0005]

In order to achieve this object, a medical training apparatus according to the present invention comprises: (a) at least three targets arranged so as to draw a polygon in space; (B) fixed at a predetermined location in space,
(C) first imaging means for photographing the movement of a subject including the at least three targets;
A second imaging unit fixed to a place distant from the imaging unit, and imaging the movement of a subject including the at least three targets simultaneously with the first imaging unit; and (d) the first imaging unit. First image processing means for processing the captured image to obtain first two-dimensional coordinate data representing the positions of the at least three targets; and (e) processing the image captured by the second imaging means A second image processing means for obtaining second two-dimensional coordinate data representing the positions of the at least three targets; and (f) obtaining the at least three targets from the first and second two-dimensional coordinate data. A third image processing means for obtaining three-dimensional coordinate data of a specific position associated with the space; (g) a training object associated with the first and second imaging means in the space; h) The above facts A storage unit storing image data of the target; and (i) a composite image obtained by superimposing the movement of the specific position on the image of the target based on the image data of the target and the three-dimensional image data. And a fourth image processing means for obtaining

Another embodiment of the medical training apparatus according to the present invention is characterized in that the image data of the training target includes shape data representing an ideal final shape according to the training content.

Another embodiment of the medical training apparatus according to the present invention is characterized in that the three targets have different colors.

Another embodiment of the medical training apparatus according to the present invention is characterized in that the three targets have different reflectances.

[0009] The method of evaluating the results of medical training according to the present invention comprises:
(A) storing image data to be trained;
(B) preparing a subject having at least three targets arranged in a space to draw a polygon and moving in accordance with the movement of the instrument handled by the medical intern;
(C) photographing the movement of the subject including the at least three targets by a first imaging means fixed at a predetermined place in space; and (d) simultaneously with the first imaging means, Capturing a movement of a subject including three targets in space by a second imaging unit fixed away from the first imaging unit; and (e) an image captured by the first imaging unit. A first image processing step of obtaining first two-dimensional coordinate data representing the positions of the at least three targets; and (f) the second image processing step of:
A second image processing step of processing an image photographed by the imaging means to obtain second two-dimensional coordinate data representing the positions of the at least three targets; and (g) the first and second two-dimensional data. A third image processing step of obtaining, from the coordinate data, three-dimensional coordinate data of a specific position associated with the at least three targets in space, and (h) the image data of the training target and the three-dimensional image data And a fourth image processing step of obtaining a composite image obtained by superimposing the movement of the specific position on the image of the training target based on the above.

[0010]

In the medical training apparatus and the evaluation method of the training result, the first imaging means and the second imaging means are provided with a subject (particularly, an object provided on a device handled by the trainee during the medical training). At least three targets). Images captured by the first and second imaging units are processed by the first and second image processing units, respectively, and two-dimensional coordinate data representing the positions of a plurality of targets is created for these images. The third image processing means associates the first and second two-dimensional coordinate data with each other, and a specific position spatially associated with the reference (for example, in the case of a dental cutting instrument, 3D image data of the cutting tool is obtained. On the other hand, the training target (for example, teeth in the case of dental training) is associated with the first and second imaging units in space, and the image data is stored in the storage unit. The fourth image processing means uses the image data of the teeth stored in the storage unit and the three-dimensional coordinate data of the specific position, and superimposes the movement of the specific position on the training target image. Create The created composite image is displayed on the display device and provided to the trainee and the supervisor in real time.

Therefore, the trainee can perform the training while visually assessing his / her training situation. Further, the instructor of the training can view the synthesized image of the display device displayed in real time and give advice to the trainee as appropriate.

When the image data to be trained includes shape data representing an ideal final work corresponding to the contents of the training, the ideal final work and the actual work can be visually compared. The result can be evaluated more objectively.

Furthermore, if the targets have different colors or different reflectivities, these targets can be easily identified on the image.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that common reference numerals in the drawings indicate the same members and portions. Further, an embodiment in which the present invention is applied to a dental training apparatus will be described. However, the present invention is not limited to this, and can be similarly applied to other medical training apparatuses and training result evaluation methods.

FIG. 1 shows the entirety of a dental treatment training device 10. The training device 10 is a device necessary for a trainee (for example, a student of a dental school, a dental treatment practitioner) 12 to perform a target dental training. It has. Specifically, the training device 10 includes a training table 14. The training table 14 is
It includes an elevating base 16, a table 18 fixed on the base 16, and an instrument holder 20 connected to the table 18 or another place. A human head model 22 is fixed to an end of the table 18, and the human head model 22 is attached to a tooth model 24 (see FIG. 3).
It is included. A column 26 is arranged on one side of the table 18. The support 26 has its lower end fixed to the table 18 or to the upper portion of the base 16 which moves up and down together with the table 18. The support 26 has a horizontal support 28 extending in the horizontal direction so as to cross over the head model 22 above the table 18.

The horizontal support 28 has imaging cameras 32A and 32B such as CCD cameras on both sides of a vertical underline 30 extending substantially vertically through the mouth of the head model 22. These imaging cameras 32A and 32B are each focused on the dental arch model 24. It should be noted that these photographing cameras 32A and 32B move up and down as the table 18 moves up and down.
The distance between 2B and the dental arch model 24 does not change or the focus is not lost. The horizontal support 28 also includes the imaging camera 3.
In this embodiment, two illumination lamps 36A and 36B are fixed in order to illuminate the shooting positions 2A and 32B.

The instrument 40 used by the trainee 12 for dental training includes an imaging camera 32 as shown in FIG.
A target to be photographed in A and 32B, that is, a subject 42 is fixed. The subject 42 has three targets 44A, 44B, and 44C arranged so as to draw a triangle in space.
Having. These targets 44A, 44B, 44C
Are fixed to the distal ends of the three arms 46A, 46B, 46C. The proximal ends of the arms 46A, 46B, 46C are connected to a ring 48 fixed to the proximal side of the instrument 40. Since the three targets 44A, 44B, and 44C are fixed to the instrument 40 in this manner, the three targets 44A, 44B, and 44C and the cutting attached to the distal end of the instrument 40 The spatial positional relationship with the device 50 is uniquely determined, and the three targets 44A, 44B, 4
If the position in the space of 4C is determined, the position of the cutting tool 50 in the space can be determined. Further, as shown in FIG. 3, a spatial positional relationship of a tooth 52 to be subjected to treatment training is obtained for the imaging cameras 32A and 32B, and in this state, three targets 44 for the imaging cameras 32A and 32B are obtained.
If the spatial positions of A, 44B, and 44C and the spatial position of cutting tool 50 are determined, the state of engagement of cutting tool 50 with tooth 52 (ie, the cutting state) can be estimated.

The targets 44A, 44B, 44C
For example, it is preferable to color the image with different colors such as red, blue, and green so that the images can be distinguished when photographed by the imaging cameras 32A and 32B. The targets 44A, 44B, 44
C itself may be formed of a lamp or a light emitting element that emits a different color. In this case, it is necessary to connect these lamps and the like to a power source in order to emit the lamps and the like. The ring 48 may be non-rotatably fixed to the instrument 40. For example, a known detent mechanism (detent mechanism) is provided, and a predetermined angle (for example, 15 degrees) about the long axis of the instrument 40 is provided. , 30 degrees, 45 degrees).

In order to visually grasp the cutting condition of the tooth 52 by the cutting tool 50, a data processing device 60 shown in FIG.
Is prepared. The data processing device 60 has an arithmetic processing unit (microcomputer) 62. Arithmetic processing unit 6
Various input units 64 are connected to 2. The input unit 64 includes, besides a keyboard and a mouse, other computers connected to the control system via a transmission system such as a communication cable. Data input from these keyboards and the like include three targets 44A,
4B, 44C (for example, the distance between the three targets 44A, 44B, 44C), the spatial relationship between the three targets 44A, 44B, 44C and the cutting tool 50, and the external shape (shape) of the cutting tool 50 Data), an imaging camera 32A based on a fixed reference point in space,
Spatial coordinates of image receiving surface of 32B / imaging cameras 32A, 32B
The optical axis coordinates (direction), the spatial coordinates and the external shape (shape data) of the treatment training target tooth 52 with respect to the reference point, and the rotation angle of the subject 42 when the subject 42 can be rotated with respect to the instrument 40. Included (step # in FIG. 5)
1). The information input from the input unit 64 is stored in the ROM 6
6 and used for arithmetic processing described later.

During the training, as shown in FIGS. 1 to 3, the trainee 12 photographs three targets 44A, 44B, and 44C fixed to the instrument 40 held by the hand (step # in FIG. 5). 2). The captured information is output from the imaging cameras 32A and 32B to the corresponding video capture boards (VCB) 68A and 68B, respectively. In the present embodiment, the VCBs 68A and 68B are
The outputs of A and 32B are converted into digital image data (step # 3 in FIG. 5). The VCBs 68A and 68B binarize the digital image data (step # 4 in FIG. 5) and create image data of the three targets 44A, 44B and 44C captured by the corresponding imaging cameras 32A and 32B, respectively. . Targets 44A and 44 created here
The image data of B and 44C are transferred to the R
Output to the OM 66 and stored there.

There are various methods for extracting the image data of each of the targets 44A, 44B and 44C while distinguishing them from the other image data. For example, each target 44A, 44
B and 44C are colored with a unique color (for example, red, blue, and green), and each target 44A, 44B, 4
When a lamp or the like that emits a color unique to 4C is used, an appropriate threshold value is provided to extract only image data of a specific color from digitized image data. this is,
In general, it is the same as the method used in a color copying machine or the like. In addition, each target 44A, 44B, 44C
Has a unique appearance, each target 44A, 44B, 44 is recognized by recognizing the appearance from the image data.
Only the image data of C can be extracted. further,
The target surfaces are covered with materials having different reflection efficiencies while maintaining the same appearance (color and shape), and the imaging cameras 32A and 32B
The differences between the image densities of the targets 44A, 44B, and 44C photographed in the steps (A), (B), and (C) indicate
It is also possible to extract only the image data of.

The target 44 stored in the ROM 66
The image data of A, 44B, and 44C is read by the arithmetic circuit 70 and processed according to the processing program stored in the RAM 72 (Step # 5 in FIG. 5). Specifically,
In the arithmetic circuit 70, based on the image data of the three targets 44A, 44B, 44C photographed by the imaging camera 32A, these three targets 44A, 44B, 44C
, Two-dimensional coordinates (position data A) indicating the position on the screen of the imaging camera 32A are calculated. Similarly, the arithmetic circuit 70 determines the three targets 44A, 44A, 44C based on the image data of the three targets 44A, 44B, 44C captured by the imaging camera 32B.
B and 44C, the imaging camera 32B
2D coordinates (position data B) indicating the position on the screen are calculated.

Next, the arithmetic circuit 70 associates the position data A and B of the three targets 44A, 44B and 44C obtained for the respective imaging cameras 32A and 32B (step # 6 in FIG. 5).

Subsequently, the arithmetic circuit 70 calculates the initial conditions (for example, the spatial coordinates of the image receiving surfaces of the imaging cameras 32A and 32B and the imaging camera 3) input from the input unit 64 as described above.
The spatial coordinates (x ′, y ′, z ′) of the three targets 44A, 44B, 44C are obtained using the position data A, B (optical axis coordinates of 2A, 32B) (step # 7 in FIG. 5). .

The arithmetic circuit 70 also calculates, based on the spatial coordinates, a spatial vector (x, x) of a specific point of the cutting tool 50 placed in a fixed spatial positional relationship with the three targets 44A, 44B, 44C. y, z, α, β, γ) (Step # 8 in FIG. 5). The space vector is used together with the initially input shape data of the cutting tool 50 to determine the space occupied by the outer shape of the cutting tool 50.

Note that these three targets 44A, 4A
The spatial coordinates of 4B, 44C and the cutting tool 50 are values with a specific fixed point in space as the origin, and the origin can be arbitrarily determined.

The arithmetic circuit 70 further uses the space vector of the cutting tool 50 and the shape data of the cutting tool 50 to obtain trajectory data representing the trajectory of the cutting tool 50 (FIG. 5).
Step # 9). In addition, this movement locus is not a point locus,
It is a space locus occupying a certain volume in space.

This trajectory data is stored in the tooth 5 for cutting training.
The data is transmitted to the graphics circuit 74 together with the shape data of the second. The graphic circuit 74 displays the shape of the tooth 52 on an appropriate display 76 based on the shape data of the tooth 52. The graphic circuit 74 superimposes the trajectory data and the shape data to obtain a spatial interference region between the cutting tool 50 and the tooth 52, that is, a tooth portion cut by the cutting tool 50, and displays the cut portion 80 on the display 76. (Step # 10 in FIG. 5).

For example, FIGS. 6 (a), 6 (b) and 6 (c)
The plane of the tooth 52 displayed on the display 76, BB
Shows the cross section, C-C cross section, in the shape of the tooth that was exposed,
The cutting portion 80 is displayed. Although FIG. 6 shows only the teeth 52 and the cut portions 80 two-dimensionally, it is of course possible to display them three-dimensionally. The shape data of the tooth 52 may include data of an ideal cutting shape according to the contents of the training, and the ideal cutting shape may be simultaneously expressed as shown by a dotted line 82 in FIG. In this case, since the ideal cut shape 82 and the actually cut shape can be visually compared and compared, the objectivity of the evaluation is improved.

The cutting portion 80 of the tooth 52 is displayed in real time as the cutting training progresses. Therefore, for example, if the display 76 is arranged at a position where the trainee can see, the trainee can perform the training while visually evaluating his or her training situation. If the display 76 is placed so that the supervisor can see it,
The supervisor can look at the training status of the trainee and give appropriate advice to the trainee.

In the above-described embodiment, three targets 44A, 44B, and 44C are photographed. However, as long as a polygon can be drawn in space, there is no problem in using more targets. If the target can draw a polygon of a triangle or more in space, and if two or more imaging cameras can simultaneously shoot in a state where a plurality of targets can draw a polygon, the instrument 40
It may be attached directly to the outer surface of the.

The video capture boards 68A and 68B are used as devices for processing the signals output from the imaging cameras 32A and 32B to generate binary image data. A signal processor may be used.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an entire medical training apparatus according to the present invention.

FIG. 2 is a perspective view showing a state where a trainee holds an instrument and a subject.

FIG. 3 is a diagram schematically illustrating a positional relationship among a dental arch model, an instrument, a subject, and an imaging camera.

FIG. 4 is a circuit block diagram of a data processing device included in the medical training device.

FIG. 5 is a flowchart illustrating processing of the data processing device.

6 (a) is a plan view of the tooth, FIG. 6 (b) is a sectional view taken along line AA, and FIG. 6 (c) is a sectional view taken along line CC. .

[Description of Signs] 12: Training device, 12: Trainee, 32A, 32B: Imaging camera, 40: Instrument, 42: Subject, 44
A, 44B: target, 50: cutting tool, 52: tooth, 70: arithmetic circuit, 80: cutting part, 82: ideal cutting shape.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Teruzo Nakayama 680 Higashihama-machi, Fushimi-ku, Kyoto-shi, Kyoto F-term in Morita Manufacturing Co., Ltd. (reference) 2C028 AA10 BB01 CA13 2C032 CA12 4C052 AA20 LL02 LL07 NN01 NN11 NN15

Claims (4)

[Claims] (A) a subject having at least three targets arranged in a space to draw a polygon and moving in accordance with the movement of an instrument handled by a medical practitioner;
(B) a first image capturing a movement of a subject including the at least three targets, which is fixed at a predetermined place in a space;
And (c) a second camera which is fixed in space at a position distant from the first imager, and simultaneously captures the movement of a subject including the at least three targets simultaneously with the first imager. (E) first image processing means for processing an image taken by the first imaging means to obtain first two-dimensional coordinate data representing the positions of the at least three targets; (e) (F) second image processing means for processing an image photographed by said second imaging means to obtain second two-dimensional coordinate data representing the positions of said at least three targets; and (f) said first and second image processing means. A third image processing means for obtaining three-dimensional coordinate data of a specific position associated with the at least three targets in space from the two two-dimensional coordinate data, and (g) the first and second imagings In terms of means and space And training target attached,
(H) a storage unit that stores the image data of the training object; and (i) the movement of the specific position in the image of the training object based on the image data of the training object and the three-dimensional image data. A medical training apparatus comprising: fourth image processing means for obtaining a superimposed composite image; and (j) a display device for displaying the composite image. 2. The training apparatus according to claim 1, wherein the image data of the training target includes shape data representing an ideal final product according to the training content. 3. The training apparatus according to claim 1, wherein the three targets have different colors. 4. The training apparatus according to claim 1, wherein the three targets have different reflectivities. (A) a step of storing image data of a training subject; and (b) a movement of an instrument having at least three targets arranged in a space to draw a polygon and handled by a medical trainee. (C) photographing the movement of the object including the at least three targets by a first imaging means fixed at a predetermined location in space; (d) Simultaneously photographing the movement of the subject including the at least three targets with a second imaging unit fixed in a space away from the first imaging unit, simultaneously with the first imaging unit;
(E) a first image processing step of processing an image captured by the first imaging means to obtain first two-dimensional coordinate data representing the positions of the at least three targets;
(F) a second image processing step of processing an image captured by the second imaging means to obtain second two-dimensional coordinate data representing the positions of the at least three targets;
(G) a third image processing step of obtaining, from the first and second two-dimensional coordinate data, three-dimensional coordinate data of a specific position associated with the at least three targets in space; (h) A fourth image processing step of obtaining a composite image obtained by superimposing the movement of the specific position on the image of the training target based on the image data of the training target and the three-dimensional image data; (i) the combining Displaying an image.