JPS6117418Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an apparatus for taking a tomographic image of a human body using a scintillation camera.

Computerized tomography using a scintillation camera has been considered in the past, but in this method the patient is seated in a chair and the scintillation camera is fixed while the chair is rotated to take images. However, this requires the patient to be rotated, causing pain to the patient, and it is especially difficult to image critically ill patients who cannot be rotated. Furthermore, as mentioned above, imaging can only be performed by having the patient sit in a chair, and if the cross section to be photographed requires the patient to lie down, the patient must be rotated. Since it is not possible to do so, it is impossible to take pictures.

The purpose of this invention is to easily enable tomography using a scintillation camera without rotating the patient.

This idea combines the rotational movement of the scintillation camera, its vertical movement, and the relative movement in the horizontal direction between the bed and the scintillation camera, to move the scintillation camera in a circular motion centered on the area to be imaged of the patient. It is characterized by causing the person to do the following. The term "horizontal motion" here refers to horizontal motion within a plane that includes the rotational surface of the scintillation camera.

An example of this invention will be explained with the help of diagrams: 1
is a stand and is equipped with a column 2, 3 is an elevating arm, 4 is a support arm that supports a scintillation camera head (hereinafter simply referred to as the camera) 5, and 6 is a stand.
is a collimator, 7 is a bed, and 8 is a rotating wheel.
The lifting arm 3 can be raised and lowered along the support 2. For this purpose, for example, the support 2 is provided with a screw shaft 9, which is rotated by a motor 10 via a gear mechanism 11. A gear mechanism 12 screwed into the lifting arm 3 is attached to the lifting arm 3. Therefore, as the screw shaft 9 is rotated by the motor 10, the lifting arm 3 is moved up and down. With respect to the lifting arm 3, the support arm 4 is rotatable around a horizontal axis, that is, around the axis of the lifting arm 3;
A motor 13 is installed at the motor 13, and its rotating shaft is connected to the lifting arm 3. This causes the support arm 4 to rotate about the horizontal axis when the motor 13 rotates. The support arm 4 is designed to be able to rotate 360 degrees. The rotation of the support arm 4 causes the camera 5 to rotate in the same way. The bed 7 is arranged to face the detection direction of the camera 5, and its longitudinal direction coincides with the axial direction of the support arm 4, and furthermore, this bed 7 is movable within a plane orthogonal to the longitudinal direction. It is said that For this purpose, for example, the motor 15 is attached to the bed 7, and its rotation is transmitted to the rotating wheel 8 through the belt 16.
The bed 7 is thereby moved.

Now, as shown in Figure 2, patient 17 on bed 7.
It is clear that when the camera 5 moves circularly around the region A to be photographed, a tomographic image of the region A to be photographed can be taken. It is understood that this means that the rotational axis B of the camera 5 only needs to move along a circle D centered on the region A to be imaged. To explain in more detail, if the camera 5 is placed in a vertical plane that passes through the region A to be photographed and is rotated about the horizontal axis in a plane that includes the circle D, the camera 5 will always face the region to be photographed. In this state, it rotates around the area to be imaged. Note that E indicates the movement locus of the center of the collimator 6. Here, if the rotation angle of the camera 5 about the rotation axis B is ω and the angular velocity is a, the rotation angle ω at any time t is expressed as ω=at...(1). Next, when the camera 5 moves on the circle D, the height position of the camera 5 at an arbitrary time t, that is, the height position h of the rotation axis B, is h=h ₀ +γsinat (2). Here, h ₀ is the height of the part A to be imaged from the reference point (for example, the floor), and γ is the radius of the circle D. Similarly, when moving on the circle D, the lateral (horizontal) position of the camera 5 at any time t, that is, the lateral position x of the rotation axis B, is x = x ₀ - γcosat... (3) It is in. Here, x ₀ indicates the lateral position of the region A to be photographed (for example, the distance along the horizontal direction from a vertical line passing through the center of the support 2 as a reference line). Therefore, if the relationship between ω, h, and x expressed by the previous equation (3) is always satisfied at any given time, the rotation axis B of the camera 5 will be on the circumference of the circle D. , and the collimator 6 faces the region A to be photographed. Here ω is motor 13
, h is determined by motor 10 and x by motor 15. Therefore, it is sufficient to control each motor according to the above equation (3).

For this purpose, it is convenient to use a microprocessor 21 as shown in FIG. That is, the rotation signals from each motor 10, 13, and 15 are given to the microprocessor 21 via the interface 22, and the microprocessor 21 calculates whether or not the relationship shown in equation (3) above is satisfied. The calculated output is given to the motor control circuit 24 via the interface 23, so that future control signals are given to each motor.

Fig. 4 shows the relative positional relationship between the camera 5 and the patient 17 at each time. Indicates a state where they overlap,
At this time, it is assumed that the movement is started in each arrow direction at time t=0. Thereafter, at time t=π/2a, as shown in FIG. 4B, the rotational axis B is on the left side of the region A to be imaged and on the same horizontal line. From this point on, the bed 7 is moved in the opposite direction. At time t=π/a, as shown in FIG. 4C, the rotation axis B reaches the vertical line below the imaged area A. From this point on, the camera 5 is raised.
Then, at time t=3π/2a, as shown in FIG. 4D, the rotational axis B reaches the right side of the imaging site and on the same horizontal line. From this point on, move bed 7 to the right. Then, it returns to the initial position at time t=2π/a. During this time, collimator 6
is always facing the area being photographed.

In the embodiments described above, the bed 7 is moved back and forth in the horizontal direction, but since this movement is just a horizontal movement, it hardly causes any pain to the patient.
Furthermore, instead of moving the bed 7, the stand 1 may be moved in the horizontal direction, and in this case, the patient can remain stationary, so that no pain is caused to the patient. Each motor can be controlled mechanically or by simple electrical control without using a microprocessor. Although the above embodiment is a machine that moves the camera and bed continuously, they may be moved intermittently instead. For example, the exercise may be performed intermittently every 2 to 10 degrees.

As detailed above, according to this invention, it is possible to take a tomographic image using a scintillation camera without moving the patient lying in bed slightly or at all, and the movement of the scintillation camera also allows the patient to There is no need for a mechanism for circular motion around the center, and the motion mechanism is simple because it is simply raised and lowered, rotated, and horizontally moved the bed (or stand).

[Brief explanation of the drawing]

Figure 1 is a side view showing an embodiment of this invention, Figure 2 is a side view showing an embodiment of this invention.
FIG. 3 is an explanatory diagram of the operating principle, FIG. 3 is a motor control circuit, and FIG. 4 is a front view showing the operating state. 1... Stand, 2... Support, 5... Scintillation camera, 7... Bed, 8... Rotating wheel,
10, 13, 15...motor, A...portion to be photographed.

Claims (1)

[Scope of utility model registration request] a support arm that is supported by the support arm so as to be able to rotate about its axis; and a camera head that is held by the support arm. a scintillation camera device comprising: a bed facing the detection surface of the camera head and disposed with its longitudinal direction along the axial direction of the support arm; a drive mechanism for raising and lowering the lifting arm; A rotational drive mechanism for rotating a support arm, a drive mechanism for relatively moving the stand or support and the bed in a plane orthogonal to the longitudinal direction of the bed, and a control mechanism for each of the drive mechanisms, The camera head is rotated around the part to be imaged set on the bed by combining the lifting and lowering of the lifting arm, the rotation of the support arm, and the relative movement of the stand or support and the bed. Characteristic tomography equipment.