JPH0420334A - Ct device - Google Patents

Abstract

PURPOSE:To configure the device so that the head part can be moved except the time of photographing the head part, and also, a straight head part tomography image can be obtained by fixing a head part holding tool being oscillatable to the left and the right to an arbitrary oscillating position, photographing the head part of a body to be examined which is inclined, and thereafter, correcting straightly a reconfigured inclined tomography image. CONSTITUTION:On the end part of a bed 1, a semicircular head rest 3 is provided, and on its lower part, a fixing part 5 for fixing it is provided projectingly. Subsequently, on the lower part of the bed 1 side of the head rest 3, a rail 7 curved to the upper part is fixed and provided, and the rail 7 is fitted into a guide groove 9 of a curved shape, so that the head rest 3 can be oscillated centering around a point O. In such a way, a body to be examined can move freely the head part except the time of photographing the head part. At the time of photographing the head part, a head part holding tool is fixed to an arbitrary oscillating position by the fixing part 5. In such a state, in order to correct an inclined tomography image, a CT value of the head rest 3 in retrieved extending from an (a) point of the center lower end to the upper part, and from a (b) point, the external shape is retrieved stepwise until the tip of a (c) point is detected, this retrieval is executed with the left and the right, and by rotating the tomography image so that a straight line for connected both the tips which are detected becomes horizontal, a straight head part tomography image is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a CT apparatus that allows a patient to move his or her head except when photographing the head.

(Prior Art) The end of a bed used in a CT apparatus such as an X-ray CT apparatus or a magnetic resonance apparatus is equipped with a headrest (head holder) for holding the head of a patient.

A conventional headrest is fixed to an end of a bed, and its inner surface is in close contact with the head. This is to keep the head straight and prevent the patient from moving it.

However, patients are unable to keep their heads still for long periods of time.
It moves inside the headrest. This causes the head to shift from the headrest.

(Problem to be solved by the invention) In this way, photographing the head with the head shifted]
7, the reconstructed tomographic image of the head is tilted. For this reason, there was a drawback that it was difficult to see the tomographic image of the head. Further, since the conventional Heradrest is fixed even when the head is not being photographed, the patient cannot freely move his head and cannot relax.

Therefore, this invention was made in view of the conventional circumstances, and its purpose is to make it possible to move the head except when photographing the head, and to make it possible to keep the head straight. An object of the present invention is to provide a CT apparatus that can obtain tomographic images.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object 1, one aspect of the present invention is to provide an end portion of the bed on which the subject is placed that swings in the left-right direction of the bed. a semicircular head holder that can be supported; a fixing means that fixes the head holder at an arbitrary swing position when photographing the head of the subject; The apparatus comprises an image correction means which straightens the reconstructed tilted tomographic image of the head after the tilted head of the subject is photographed while being fixed in a swinging position.

Another invention provides a semicircular head holder that is supported at an end of a bed on which a subject is placed so as to be swingable in the left-right direction of the bed, and a device for photographing the head of the subject. and a fixing means for fixing the head holder to a swinging position in which the head holder is straight, so as to reconstruct a straight tomographic image of the subject's head. It is configured.

(Action) "In the two-section structure, one of the inventions is ? 1' A circular head holder is swingably supported at the end of the bed. Except when photographing the head of a subject placed on a bed, the subject can freely move his or her head without moving. When photographing the head, the head holder, which is swung as the subject moves the head, is fixed at an arbitrary swiveling position by the fixing means. Then, the tilted head is photographed and reconstructed, and the tilted tomographic image of the head is corrected to be straight by the image correction means.

Further, in another invention, a semicircular head holder is swingably supported at the end of the bed. Except when the head of the subject placed on the bed is being photographed, the subject can freely move his or her head. When photographing the head, the head holder, which is swung as the subject moves the head, is fixed by the fixing means to a swiveling position where it becomes straight. Then, the head is photographed and a straight tomographic image of the head is reconstructed.

(Embodiments) Two embodiments of the present invention will be described below with reference to the drawings.

FIG. 1(A) is a side view showing a headrest (head holder) provided in an OCT apparatus according to one embodiment of the present invention, FIG. 1(B) is an iJE plane view of the headrest, and FIG.
C) is a sectional view showing a crosspiece for fixing the headrest.

In Figure (A), a headrest 3 is provided at the end of the bed 1. At the bottom of headrest 3,
A fixing part 5 for fixing the headrest l-3 projects from the end of the bed 1.

As shown in FIG. 1(B), the headrest 3 has a semicircular shape, and the lower part of the headrest l-3 on the side of the bed 1 has a
” A rail 7 curved in two directions is fixedly installed.

As shown in FIG. 1(C), the rail 7 is fitted into a curved guide groove 9 provided at the tip of the bed 1-, and moves along the guide groove 9 in a pendulum shape. Thereby, the headrest 3 can swing around point O in FIG. 1(B).

In FIG. 1(C), the fixed part 5 includes a motor 1], a gear 13, a screw 15, a link mechanism]7, and a pressing part 9.
It consists of

The motor] 1 is driven by instructions from a control section (not shown).

The gear 13 is rotated by being driven by the motor 11.

The screw 15 moves in the front-rear direction of the bed as the gear 13 rotates.

The link mechanism 17 is driven as the screw 15 moves,
This is for bringing the pressing part 19 into contact with the rail 7 or separating it from the rail 7.

The pressing portion 19 is configured to press the rail 7 and fix the headrest 3 by moving the screw 15 toward the rear of the bed 1. Furthermore, when the screw 5 moves forward of the bed 1, the pressing part 19 is separated from the rail 7 and releases the fixation of the headrest 3.

One embodiment of the present invention has thus been constructed and will now be described in detail.

A patient (not shown) to be examined is placed on a bed 1 and his head is held on a headrest 3.

At this time, since the pressing portion 19 is separated from the rail 7, the patient can freely move his head. Thereby, the headrest 3 is swung left and right.

When photographing the head, an instruction to fix the headrest 3 is output from the control unit to the motor 11 by an operator (not shown) operating a console (not shown) or the like at any swing position of the headrest 3. be done.

The motor 11 is driven by this instruction, and the gear 13 is rotated by the rotation of its tip. As a result, the screw 15 is moved to the rear of the bed 1, and the link mechanism 17 is driven accordingly.

Furthermore, the suppressing part 19 is moved in the same direction as the screw 15,
The rail 7 is pressed. As a result, the headrest 3 is
Fixed in any swing position.

After the headrest 3 is fixed in this way, the head is photographed.

In addition, when imaging other than the head, for example, when the operator is planning the imaging, or while the operator is observing the reconstructed tomographic image after the head has been imaged, or when imaging other than the head, such as the abdomen, , an instruction to release the fixation of the headrest 3 is given to the motor]1.

The motor 11 is driven by this instruction, and its tip is rotated in the opposite direction to when the headrest 3 is fixed. As a result, the screw 15 is moved to the front of the bed 1, and the pressing portion 19 is separated from the rail 7 through the drive of the link mechanism 17. As a result, the fixation of the headrest 3 is released.

In this way, the patient can freely move his or her head except when the head is being photographed.

On the other hand, after the headrest 3 is fixed at an arbitrary swinging position and the tilted head is photographed, the reconstructed tomographic image is similarly tilted.

Next, an example of a method for straightening this inclined tomographic image of the head will be explained using FIGS. 2 to 4.

FIG. 2 is a tomographic image of the tilted headrest 3 and the head 21.

The CT value of the headrest 3 is searched from the bottom center of the image (point a in the figure) toward the top of the image. When the CT value of the headrest 3 is detected at point b, the outer shape is further searched in a stepwise manner until the tip is detected as indicated by C in the figure. This search is performed for the left and right sides of the headrest 3, and the left and right tips are detected. A straight tomographic image of the head can be obtained by rotating the tomographic image so that the straight line connecting the detected image tips becomes horizontal.

Further, as a method of straightening a tilted tomographic image of the head, a method of embedding a gauge 23 in the headrest 3 can be considered.

Figure 3 shows a headrest 3 in which three gauges 23 are embedded.
FIG. The gauge 23 is a thin rod-shaped thing made of a material with a particularly low CT value or a material with a particularly high CT value.

The head held in the headrest 3 in which the gauge 23 is embedded is photographed, and the reconstructed tilted tomographic image is shown in FIG.

To straighten this tomographic image, the bottom center of the image (
The CT value of the headrest 3 is searched upward in the image from point d in the figure). At point e, C of headrest 3
When the T value is detected, the center O is determined using the distance R from the point e to the rotation center 0 of the headrest 3.

Furthermore, for each gauge 23, from the center O to the gauge 23
Search for "circumference with distance love as radius" 2, gauge 2
Detect a CT value of 3. Three gauges 23 detected
so that the triangle formed by is at the original placement angle,
By rotating the tomogram, a straight tomogram of the head can be obtained.

In this way, according to this embodiment, the patient can freely move his or her head except when the head is being photographed. Furthermore, when photographing the head, by fixing the headrest 3 to an arbitrary swinging position, a tilted tomographic image can be corrected to be straight.

Next, another embodiment will be explained using FIGS. 5 and 6.

FIG. 5 is a front view for explaining the mechanism for fixing the headrest 3 provided in the CT apparatus of this embodiment, and FIG. 5(A) is a diagram when the headrest 3 is not fixed. , FIG. 5(B) is a diagram when the headrest 3 is fixed.

Note that the headrest 3 is the same as that shown in FIGS. 15(A) and 15(B).

As shown in FIG. 5, the rail 25 has a curved shape, and the lower part thereof is formed in a wave shape.

Also, on the left side of the rail 25, there is a hole 27 for detecting the swing position.
is opened.

On the left side of the guide 9, two sensors for detecting the swing position are fixed to the guide 9 with the rail 25 in between.

Further, a screw 31- is provided below the rail 25, and the tip thereof meshes with a gear 35 at the tip of a motor 33. The screw 3] and the motor 33 are provided so as to be movable in the vertical direction at the same time.

This embodiment is constructed in this way, and the operation of this embodiment will be explained next.

As shown in Figure 5 (A), except when photographing the head, screw 31
Since the motor 33 has been moved downward, the headrest 3 is in an unfixed state. For this reason,
The patient can move his head freely.

1. When photographing the head, as shown in FIG. 5(B), the screw 31 and motor 33 are moved upward by the operator's operation on the console, etc.
It is meshed with. At the same time, an instruction to fix the headrest l-3 is given to the motor 33.

The motor 33 is driven by this instruction, and the gear 35 at the tip thereof is rotated, thereby rotating the screw 31. As the screw 31 rotates, the rail 25 is moved left and right along the guide 9.

The hole 27 provided at the left end of the rail 25 is the sensor 2.
9, it is detected by two sensors. FIG. 6 is a sectional view showing how the sensor 29 detects the hole 27.

A mirror 37 is fixed to the guide 9 at a position corresponding to the two sensors. By placing the hole 27 between the two sensors and the mirror 37, the signals output from the two sensors are
The signal is reflected by the mirror 37, and this reflected signal is further received by two sensors to detect the hole 27.

When the hole 27 is detected, this is transmitted to the control section, and furthermore, the control section instructs the motor 33 to stop driving +h. As a result, the driving of the motor 33 is stopped, and the rotation of the screw 31 via the gear 35 is stopped. As a result, the movement of the rail 25 is stopped and the headrest 3 is fixed in a straight position.

When the head is photographed with the headrest 3 fixed straight, the reconstructed tomographic image will also be straight.

After the photographing is completed, while the operator is observing one photographed image or a tomographic image, the motor 33 and the screw 31 are moved downward according to instructions from the control section. This releases the fixation of the rail 25, allowing the patient to move his head freely.

In this way, according to this embodiment, when photographing the head,
Forcibly fix the headrest 3 in a straight position.

Therefore, the reconstructed tomographic image of the head will also be straight.

[Effects of the Invention] As explained above, in the CT apparatus according to the present invention, the head rest is fixed when imaging the head, and is released at times other than when imaging. The patient is able to move his head freely. This allows the patient to relax and relieve tension. Furthermore, if a tilted tomographic image is obtained, it can be corrected to make it straight, making it easier for the operator to view the tomographic image.

[Brief explanation of the drawing]

FIGS. 1A to 4C are a side view, a front view, and a sectional view showing a headrest according to an embodiment of the present invention, and FIGS. 2 to 4 are a method for straightening an inclined tomographic image. FIGS. 5 and 6 are a front view and a cross-sectional view for explaining another embodiment. 3...Headrest 5...Fixing part 7...Rail 9...Guide 19...Press part 23...
・Gauge 25...Rail 27...Hole 29
...Sensor 3]...Screw 37...Mirror

Claims (2)

[Claims] (1) A semicircular head holder supported swingably in the left-right direction of the bed at the end of the bed on which the subject is placed; a fixing means for fixing the holder at an arbitrary swinging position; and after the head holder is fixed at an arbitrary swinging position and the tilted head of the subject is photographed, the reconstructed head is photographed. A CT apparatus characterized by comprising: image correction means for correcting a tilted tomographic image to be straight. (2) A semicircular head holder supported swingably in the left-right direction of the bed at the end of the bed on which the subject is placed; A CT apparatus comprising a fixing means for fixing the head holder to a swinging position where the holder is straight, and reconstructing a straight tomographic image of the subject's head.