JP4651591B2 - Positioning device - Google Patents

Description

  The present invention relates to a patient positioning device used in a radiotherapy device, a particle beam therapy device, an image diagnosis device, and the like, for example, using measurement light and optical measurement means capable of two-dimensional and three-dimensional measurement using a camera. The present invention relates to a positioning device that positions a diseased part of a patient at a predetermined position and angle at the time of treatment, treatment planning, or diagnosis.

  A conventional flow of the positioning operation of the patient in the radiation therapy or the particle beam therapy will be described with reference to FIG. In radiation therapy, particle beam therapy, and image diagnosis, it is necessary to match the radiation field or particle beam field with the position and shape of the affected area to be treated. First, in step 1, patient acceptance is performed, and after registration and informed consent are performed, a CT image is acquired using an X-ray CT apparatus in step 2. In step 3 of creating a treatment plan, a region to be irradiated, that is, a treatment target region is set based on the CT image. After the treatment plan is completed, a patient fixture and other jigs necessary for treatment are manufactured based on the treatment plan. At the time of treatment irradiation, it is necessary to accurately irradiate the treatment target area with radiation or particle beam. For this purpose, the following procedure is performed in step 4 called rehearsal.

  Rehearsals are usually performed on different days prior to treatment irradiation. In rehearsal, the CT image is processed to create a new image, and patient positioning is performed based on the processed image. When the patient position at the time of irradiation is determined in this way, a new two-dimensional X-ray fluoroscopic image is taken and used as a reference position image, and positioning information associated therewith is referred to as reference position data. The reason for following such a procedure is that the image quality of the X-ray fluoroscopic image taken in the positioning step before irradiation is different from that of the X-ray CT image.

  Even during treatment, the patient is positioned immediately before irradiation in order to irradiate the treatment target region with high accuracy. In step 5, coarse positioning is usually performed with a laser pointer, and then high-precision positioning is performed using an X-ray fluoroscopic image. The X-ray fluoroscopic image acquired at this time is called a positioning image. The alignment position of the laser pointer used for rough positioning is marked on the patient's body surface during rehearsal. At this time, as shown in FIG. 9F, the specific part of the affected part determined by the image diagnosis and an arbitrary part are moved to the body surface corresponding to the treatment plan, and the affected part position marker and the position marker are attached to the position. The patient was positioned by referring to the marker and making it correspond to a laser pointer or the like, and visually or using a video camera capable of two-dimensional measurement.

  In order to position a patient three-dimensionally with a video camera capable of two-dimensional measurement, two or more video cameras are required. By reading three or more position markers provided on the patient's body surface from different directions, the three-dimensional position of the affected area of the patient is estimated, and the center of the irradiation area (irradiation field), the center of the affected area, and the irradiation field The patient was positioned by moving and rotating the treatment table so that the direction of the patient and the direction of the affected area coincided with each other.

  In high-accuracy positioning using an X-ray fluoroscopic image, the setting position and setting angle of the treatment table are adjusted until the difference between the positioning image and the reference position image is within an allowable range. In the case of the patient's posture correction, that is, in the case of the supine position, the patient's lying on the treatment table may be corrected, and in the case of the sitting position, the patient's sitting on the treatment table may be corrected. Then, irradiation of step 6 is performed. In particle beam therapy and radiation therapy, positioning is reproducible because it is divided into several days at a maximum of about 40 times. The positioning procedure of the above steps is repeated for each irradiation. The procedure described here is a general procedure, and other procedures are also performed. In addition, there exist patent document 1-patent document 3 as a patient positioning device of this field | area, for example.

JP-T-2002-528168 Special Table 2000-515794 Japanese Patent Laid-Open No. 11-183143 Haruhisa Okuda, Manabu Hashimoto, Kazuhiko Kusumi “Error Reduction Techniques for Spatial Coding Using Reference Images”, 17th Annual Conference of the Robotics Society of Japan, September 9-11, 1999

  As shown in FIGS. 9 (F), 14 and 15, a patient positioning method in a conventional radiotherapy apparatus or particle beam therapy apparatus is provided with a plurality of lesion position display markers (FIG. 9 (F) on the patient's body surface. ) 50a, 50b, 50c, 50d, 50f, and 50e) in FIG. 15 are used, and two or more video cameras capable of two-dimensional measurement are used, and these affected part (lesion part) position display markers from different directions Is used to estimate the three-dimensional position of the affected area of the patient, and move and rotate the treatment table so that the center of the irradiation area (irradiation field) and the center of the affected area (target area) coincide with each other. The patient was positioned so that the position and angle of the affected area coincided with the irradiation field of the radiation or particle beam to be irradiated.

  However, this method calculates the three-dimensional position of the affected part of the patient by reading a plurality of affected part position display markers provided on the surface of the patient's body using a video camera capable of two-dimensional measurement. Referencing multiple affected area center position markers on the surface and positioning the affected area with high accuracy requires high-precision marking on the horizontal and vertical surfaces on the body surface, and the affected area position display on the body surface The number of markers needs to be at least 3 or more.

  Such a conventional method has a problem that an error occurs when a marker is applied to the body surface. Further, since the human body to be measured is not a rigid body, there has been a problem that positioning errors are likely to increase when the human body is deformed in a non-rigid manner. In addition, it is necessary to install two or more cameras, and there is a problem that it is easy to receive restrictions on installation. Furthermore, since it is difficult to remove the rotational angle error only by combining two-dimensional information, there is a problem that it takes time until the alignment is converged within the allowable range. In addition, since it is limited only to markers and local information, the reproducibility of the entire body position such as limbs and neck tilt is poor, and there is a problem that it takes time until the focusing converges.

  The present invention has been made in order to solve the above-described problems, and is positioned on a patient's body surface in a patient positioning device used for radiation therapy, particle beam therapy, treatment planning, image diagnosis, and the like. An object of the present invention is to provide a positioning device that does not require the use of a display marker, can correct a three-dimensional rotation angle that has not been obtained by measurement of conventional two-dimensional data, can reduce positioning time, and can perform positioning with high accuracy. And

The positioning apparatus according to the present invention measures reflected light reflected from a patient's body surface on a patient support table by two-dimensional measurement and three-dimensional measurement using measurement light and a camera, and forms a two-dimensional image as position data. Body surface shape measuring means for obtaining data and three-dimensional position data, body surface reference position data of the patient obtained in advance by the body surface shape measuring means, and body surface of the patient obtained by the body surface shape measuring means at the time of measurement Data collation means for comparing and collating with measurement position data to calculate a difference, input information of the data collation means, and a position for positioning by moving the patient support table in a direction in which the difference falls within an allowable range Adjusting means, and using the body surface shape measuring means, the body posture state in a part other than the peripheral part of the affected area of the patient is measured to obtain measured body position data, and the data collating means Oite, and the measurement Positions data, by comparing and collating the said surface reference position data of a portion corresponding thereto, is characterized in that to determine the difference.

  According to the positioning device of the present invention, in a patient positioning device used for radiation therapy, particle beam therapy, treatment planning, image diagnosis, etc., it is not necessary to use an affected part position display marker on the patient's body surface, and the camera field of view. Since the body surface position data consisting of the two-dimensional image data and the three-dimensional position data is obtained, the feature area of the body surface is extracted using the two-dimensional image data, and then the feature area is narrowed down to the three-dimensional area. Since the patient can be positioned by selectively comparing and comparing the position data, high-accuracy positioning can be performed in a short time.

Embodiment 1 FIG.
Hereinafter, a first embodiment of a positioning device according to the present invention will be described with reference to FIGS. 1, 2, 3, 4, 5, and 6. FIG. 1 is a layout view showing an irradiation head, a treatment table, and a patient of a particle beam therapy system. FIG. 2 is a system block diagram including a particle beam accelerator, an irradiation head, a treatment table, a control device thereof, and a patient of the particle beam therapy apparatus. FIG. 3 is a system block diagram of a two-dimensional and three-dimensional optical measurement device mounted on the irradiation head of the particle beam therapy system. FIG. 4 is a diagram illustrating a timing chart of optical measurement when a patient is positioned using a two-dimensional and three-dimensional optical measurement device. FIG. 5 shows an apparatus for positioning a patient using the position data as collation data specialized for a feature pattern (or a feature area including the feature pattern) on the patient body surface using a two-dimensional and three-dimensional optical measurement device. FIG. FIG. 6 is an operation state diagram at the time of positioning.

  In FIG. 1, 1 is a particle beam treatment irradiation head, 2 is a patient, 3 is a treatment table (patient support table), 4 is an X-ray detector, 5 is a rotation drive mechanism, 5a is a horizontal rotation axis of the irradiation head, 5b is an isocenter, 6 is a particle beam, 7 is a deflecting electromagnet, 8 is a scatterer, 9 is an X-ray tube, 10 is a multi-leaf collimator, 11 is a pattern light source, 13a is a scanning pattern light that is a pattern of light, and 13c is Reflected pattern light that is reflected light from the patient body surface, 14 is a video camera, 15 is a video monitor, 16 is a keyboard, 17 is a light localizer, and 18 is a laser pointer. (A) is a front layout diagram with the video monitor 15 of (B) removed, and (B) is a side layout diagram of (A).

  In FIG. 2, reference numeral 11 a denotes a pattern light source controller, which gives control data to the pattern light source 11. Also, 20 is a particle beam accelerator, 21 is a beam transport system, 22 is an accelerator controller, 23 is a rotation controller, 24 is an irradiation head controller, 25 is a treatment table controller, 26 is a signal processor, and 27 is an image processor. A computer, 28 is an accelerator control computer, and 29 is an irradiation system control computer. In FIG. 3, 12a is a uniform pattern light (environmental light such as room illumination light), 31 is a laser modulation circuit, 32 is a laser light source, 33 is a modulated laser light, 34 is a pattern light generator, 35 is a pattern light, 36 Is a scanner mirror, 37 is a mirror drive circuit, and 38 is a driver. The scanning pattern light 13a is used to obtain two-dimensional image data, and the uniform pattern light 12a is used to obtain three-dimensional position data. The reflected light (reflected pattern light 13c caused by the scanning pattern light 13a and reflected pattern light 13c caused by the uniform pattern light) reflected from the surface of the patient is photographed by the video camera 14 from any light source. In this example, the pattern light source and the video camera are mounted on the irradiation head. However, as described in the seventh embodiment, these devices are mounted on the ceiling or wall of the irradiation room or on a pedestal installed in the treatment room. You may use by the method of attaching.

  As shown in FIG. 3, the body surface shape measuring means is mainly configured by a pattern light source 11, a pattern light source controller 11 a, a video camera 14, and a signal processing device 26. Further, the image processing computer 27 corresponds to data collating means, and the treatment table control device 25 corresponds to position adjusting means. When positioning the patient, the body surface shape measuring means performs two-dimensional measurement and three-dimensional measurement of the patient body surface shape using measurement light and a camera, and two-dimensional image data and three-dimensional position data serving as position data. In the data collating means, the body surface reference position data of the patient to be treated or diagnosed in advance by the body surface shape measuring means and the body surface measurement position data of the patient obtained by the body surface shape measuring means at the time of measurement Are compared and calculated, and the adjustment amount of the patient support is calculated so that the difference is within the allowable range, and the output information of the data verification means is input by the position adjustment means, and the difference is allowed. The patient is positioned by moving the patient support base in the direction that falls within the range according to the adjustment amount.

  Next, the operation will be described. 1 and 2, a particle beam 6 accelerated by a particle beam accelerator 20 of a particle beam therapy system is guided to an irradiation head 1 by a beam transport system 21 and deflected in a necessary direction by a deflecting electromagnet 7 to be a scatterer. 8 is spread to a particle beam having a scattering angle necessary for treatment irradiation. The particle beam 6 that has exited the scatterer 8 is irradiated with the multi-leaf collimator 10 at the affected area of the patient 2 after shaping the irradiation field of the particle beam. The irradiation head 1 is rotated around the horizontal rotation axis 5a including the isocenter 5b by the rotation driving mechanism 5, and the particle beam 6 is directed to the patient 2 from an arbitrary direction within a plane perpendicular to the rotation axis 5a including the isocenter 5b. Irradiated. The patient 2 is fixed to a treatment table top plate (patient support table top plate) 3a, and the treatment table top plate 3a moves back and forth, right and left and up and down with respect to the support leg 3b of the treatment table 3, and the support leg is centered. Horizontal rotation is possible. Further, the support leg 3b can be rotated horizontally around the vertical rotation center axis including the isocenter 5b, and the patient 2 on the treatment table top 3a is placed at an arbitrary position and angle (direction) with respect to the irradiation field of the particle beam. be able to.

  As shown in FIG. 16 described above, two-dimensional and three-dimensional measurements are performed with a two-dimensional and three-dimensional optical measurement device during rehearsal of radiation therapy and particle beam treatment step 4, and two-dimensional image data of the patient's body surface is obtained. And three-dimensional position data are acquired and recorded in the memory of the image processing computer 27 as body surface reference position data. Two-dimensional image data and three-dimensional position data (these position data are referred to as body surface measurement position data) acquired in advance by the two-dimensional and three-dimensional optical measurement devices at the time of radiotherapy and particle beam treatment in step 5 and in advance. The body surface reference position data that has been measured are compared and collated, and the patient is positioned so that the difference is zero (or within an allowable range). In the comparison and collation, out of the acquired two-dimensional and three-dimensional position data, the two-dimensional image data is used for extracting a feature region (or a feature pattern in the feature region) on the body surface and used for comparison and collation of the affected part position in the feature region. There are a case of using only three-dimensional position data and a method of comparing and collating positions by using two-dimensional image data and three-dimensional position data in exactly the same way. In any case, since the collation for positioning is performed focusing on the characteristic region, the time required for positioning can be shortened while maintaining the positioning accuracy.

  Next, acquisition of three-dimensional position data will be described. As shown in FIG. 3, a modulated laser beam 33 is emitted from a laser light source 32 modulated by a laser modulation circuit 31. The pattern light 35 is incident on the body surface of the patient 2 as the scanning pattern light 13 a by the operation of the modulated laser light and the scanner mirror 36. The scanning pattern light 13a incident on the body surface of the patient 2 is reflected from the body surface of the patient 2 to become reflected pattern light 13c, and a part thereof is observed by the video camera 14 for observing the body surface of the patient. By reading the reflected pattern light 13c reflected from the patient's body surface with the video camera 14, the shape of the patient's 2 body surface irradiated with the pattern light 35 can be measured as three-dimensional position data. The scanner mirror 36 is swung around the rotation axis of the scanner mirror 36 so that the scanning pattern light 13a covers a necessary measurement area on the body surface of the patient 2, and converts the pattern light 35 into the scanning pattern light 13a. ing.

The driver 38 is a generation circuit for timing signals and control signals to be sent to the laser modulation circuit 31, the mirror drive circuit 37, and the signal processing device 26. The three-dimensional position of the body surface can be obtained from the distance between the reflection point of the scanner mirror 36 and the light receiving point of the video camera 14 and the swing angle of the scanning pattern light 13a. The swing angle of the scanning pattern light 13 a is determined by the timing of the timing signal sent to the laser modulation circuit 31. As an example of the measurement method described here, there is a spatial coding method using a light section method. For example, “Error reduction method of spatial coding method using reference image” Haruhisa Okuda, Manabu Hashimoto, Kazuhiko Sumi, 17th Japan There are academic conferences of the Robotics Society (September 9-11, 1999).
When obtaining two-dimensional image data, the light source is ambient light (interior illumination light or the like) that is uniform pattern light 12a, and can be obtained by capturing an image of the body surface of patient 2 with video camera 14. it can.

  FIG. 4 is a diagram illustrating a timing chart of pattern light in two-dimensional and three-dimensional light measurement. A (T 0) is a timing chart when the uniform pattern light 12 a is irradiated. At time T 0, the ambient light 12 a is turned on, the body surface of the patient 2 is illuminated, and a part of the reflected light is observed by the video camera 14. Two-dimensional image data is acquired. The imaging area by the video camera 14 corresponds to a measurement area of the three-dimensional position data (an irradiation area of the pattern light 35). B1 (T1), B2 (T2)... Bn (Tn) are timing charts of a plurality of types of modulated laser beams 33 emitted from the laser light source 32 after the time T1. The modulated laser light 33 emitted from the laser light source 32 is patterned into a pattern light 35 by a pattern light generator (not shown), converted into a scanning pattern light 13a via a scanner mirror 36, and has angle information. The body surface of the patient 2 is irradiated as the scanning pattern light 13a. The reflected pattern light 13c from the body surface by the scanning pattern light 13a is observed by the video camera 14, and the three-dimensional position data of the patient's body surface is acquired.

As the collation data for positioning at the time of particle beam irradiation, two-dimensional image data obtained by measuring the body surface of the patient 2 using a two-dimensional and three-dimensional optical measuring device attached to the irradiation head 1 at the time of positioning before treatment, and Three-dimensional position data is acquired, captured in the image processing computer 27, and recorded. On the other hand, two-dimensional image data and three-dimensional position data of the patient's body surface are acquired in advance at the time of treatment planning, and are captured and recorded in the image processing computer 27 as body surface reference position data.
FIG. 5 is a device layout diagram when performing patient positioning and particle beam therapy using the two-dimensional and three-dimensional optical measurement devices mounted on the irradiation head 1 of the particle beam therapy device.

  FIG. 6 shows the comparison of the two-dimensional image data and the three-dimensional position data (body surface reference position data) with the three-dimensional position data (body surface measurement position data) obtained by measuring the patient's body surface, and positioning the patient. FIG. 5 and 6, reference numeral 2a denotes an affected part, 2b denotes an affected part outline, 2c denotes an affected part center, and 2e denotes a two-dimensional and three-dimensional optical measuring device of the irradiation head 1 when the patient 2 is first placed on the treatment table 3. Reference body position, which is data of the measured body surface, 2d is a body surface shape (body contour indicating the current state) obtained from 2D image data and 3D position data, which is body surface measurement position data, and 13b is 3D. The scanning pattern light irradiation field of an optical measuring device is shown, respectively. In FIG. 6, a feature pattern 46 (for example, a hesso) on the body surface of the patient 2 using the two-dimensional image data out of the two-dimensional image data and the three-dimensional position data acquired using the above-described two-dimensional and three-dimensional optical measurement devices. ), 47 (for example, the right areola), and 48 (for example, the left areola) are extracted, and the feature pattern and its neighboring region are used as the respective feature regions. Next, the patient 2 is positioned by comparing with the body surface reference position data using the three-dimensional position data of the body surface in the feature region.

  At this time, one piece of three-dimensional position data corresponds to one piece of two-dimensional image data. That is, one piece of three-dimensional position data (x, y, z) corresponds to body surface feature pattern coordinates (u, v) on the two-dimensional image data. In FIGS. 5 and 6, 17a is a cross line of the light localizer, and 17b is an intersection of the light localizer cross lines. 44a is a body surface irradiation field center point. Reference numeral 49a denotes a body surface affected part center point (H) indicating a position where the affected part center is projected in the vertical direction (irradiation direction) and intersects the body surface. 49b is a body surface affected part center point (V) in a horizontal plane.

  Next, the collation method will be described. At the time of collation, in the feature region extracted based on the above-described two-dimensional image data, the body surface reference position data of the three-dimensional position data in the region and the body surface measurement position data are compared and collated, and the neighboring three-dimensional position The data is provisionally matched, the verification is repeated, the adjustment amount is calculated, and the patient is positioned by rotating the treatment table 3 back and forth, left and right, up and down and in a horizontal plane so that the difference is minimized. As the feature region, a method of selecting a region having a large shading change in 2D image data as a feature, and in addition to this, a change in the body surface shape indicated by the corresponding 3D position data is relatively large and continuously changed. This is selected by a method for selecting an area to be performed.

  It is assumed that the feature region on the body surface is a region including a feature pattern 46 (neck periphery) and a feature pattern 47 (right areola). From the body surface measurement position data Db of the three-dimensional position data obtained by measuring the body surface of the patient 2 using the three-dimensional measurement optical measurement device attached to the irradiation head 1, the point P 1 is taken along the contour of the feature pattern 47. , P2, P3... Pn. Similarly, points P1 ′, P2 ′, P3 ′... Pn ′ along the contour of the feature pattern 47 from the body surface reference position data Da of the three-dimensional position data. With respect to the three-dimensional position data of a plurality of positions on the body surface, the position data located closest in three dimensions are temporarily associated with each other, and the process for obtaining the temporary position and orientation conversion parameters is performed gradually in order to match them. The final position and orientation conversion parameters are obtained.

  That is, the distances in the three-dimensional space in the x, y, and z directions between P2-P2 ', P3-P3', and Pn-Pn 'are respectively x1, x2, x3 ... xn, y1, y2, y3 ... yn, z1, z2 , Z3... Zn, and the distances xk, yk, zk (k = 1... N) are minimized or their sum is minimized via the irradiation system control computer 29 and the treatment table control device 25 of FIG. The patient support table 3 and the patient support table top plate 3a can be gradually moved or rotated to bring the patient position close to the position at the time of obtaining the reference position data. Further, by adding the position data of the feature pattern 46 to the position data of the feature pattern 47 and obtaining the position and orientation conversion parameters, the patient 2 on the patient support table 3 is moved to the affected part center 49a shown in FIG. As shown to (B), it can set with high precision by the vicinity of the irradiation field center 44a. FIG. 6A shows the patient position on the treatment table before treatment. FIG. 6B shows a state in which the affected part center 2c of the patient 2 on the treatment table 3 is moved in the vicinity of the center 49a of the irradiation field, and the direction is set in the vicinity of the direction at the time of treatment planning (FIG. 6B). Position and orientation).

  In this way, the body surface of the patient is measured using the optical measuring device attached to the irradiation head 1 and capable of two-dimensional and three-dimensional measurement, and two-dimensional image data and three-dimensional position data are obtained. The body surface feature area is extracted from the image data, and the three-dimensional position data to be compared and matched in the vicinity of the corresponding position can be narrowed down, so that highly accurate patient positioning can be performed and at the same time the matching result can be derived. . Based on this result, as shown in FIG. 6, the treatment table 3 is moved and rotated to position the patient.

The operation of the treatment table 3 is instructed by an operator, and the display screen of the video monitor 15 disposed in the vicinity of the treatment table 3 (or a display screen provided separately from the video monitor 15). If the adjustment amount is displayed, the operator gives an instruction by inputting the adjustment amount by operating the keyboard 16 and automatically moves the patient support table 3 to make the adjustment.
In the present embodiment, the pattern light source 11 and the video camera 14 are mounted on the irradiation head 1, but these devices may be attached to the ceiling or wall of the irradiation room or a pedestal installed in the treatment room.
In this way, when narrowing down the feature region using only two-dimensional image data is appropriate, using two-dimensional image data and three-dimensional position data together, compared to using only three-dimensional position data. Time can be shortened. In addition, since three-dimensional measurement is used, reproducibility is high compared to collation using only two-dimensional measurement.

Embodiment 2. FIG.
In the first embodiment, a specific body surface feature pattern in a three-dimensional light measurement region is extracted using two-dimensional image data, and three-dimensional position data (three-dimensional position data out of body surface measurement position data acquired at the time of treatment) An example of positioning by comparing with a certain surface) and body surface reference position data was shown. However, there are cases where the body position is significantly different from the state at the time of diagnosis or treatment planning, such as the position of the part other than the affected part, for example, the position of the upper arm, head and neck, leg, and the torsion of the entire trunk. In such a case, sufficient alignment may not be achieved by simply translating or rotating the treatment table in the six-axis directions. Therefore, the posture status (trunk of the trunk, flexion and extension of the limbs, tilting of the head and neck, etc.) in the part other than the peripheral part of the affected part of the patient is measured, and the measured posture data is obtained to determine the change in the patient's posture and correct the posture I will describe how to solve this problem.

  FIG. 5C shows an arm pattern 48a that is a part that is relatively easy for the patient 2 to move during treatment and a part other than the peripheral part of the affected part. In addition, there are a head and neck part, a leg part, etc. as a part where patient 2 is easy to move. The body surface feature pattern to be measured when detecting the body position of the patient is taken as the arm part pattern 48a, and the three-dimensional body surface measurement position data (measurement position data) relating to the body surface position is obtained by the three-dimensional optical measurement device. The data including the data of the pattern 48a is acquired (in this case, the body surface measurement position data of the arm pattern 48a becomes the measurement body position data), and the three-dimensional body surface reference position of the part corresponding to the arm pattern 48a is obtained. Compare with the data and calculate the difference in position between the two. If the calculated difference exceeds the permissible value, the body position of the measurement target (in this example, the arm) should be adjusted using a method other than moving the treatment table, such as stretching the bent arm. Positioning with higher accuracy can be performed by bringing the difference in body posture within an allowable range while correcting it in the direction to match the body posture at the time of obtaining the surface reference position data, and measuring and collating again. Note that the image processing computer 27 constituting the data collating means has a database for specifying a part other than the peripheral part of the affected part, which is a measurement target when detecting the body position, according to the treatment part. The site selection for acquiring the site data (measurement body position data, etc.) becomes suitable in a short time.

  Thus, before positioning the affected area 2a, body position correction is performed using a body surface characteristic area (area including a body surface characteristic pattern) of a part other than the peripheral area of the affected area, which is not normally used for positioning the affected area. When the reference position is determined using three-dimensional measurement to a part that is not directly related to the position of the affected area, the reproducibility of the entire body position of the patient is increased, and the conventional method is limited to markers and local information only In comparison, the reproducibility of the entire body position such as the inclination of the limbs and the neck is improved, the time until the positioning is converged can be shortened, and the effect of improving the reproducibility of the positioning can be obtained. Moreover, in the collation regarding these postures, it is possible to shorten the collation time by using three-dimensional data.

Embodiment 3 FIG.
In the first embodiment described above, description is made according to the positioning flow of FIG. 16, and an example of acquiring the reference position image (body surface reference position data) during the rehearsal of step 4 has been shown, but as shown in the flow of FIG. In addition, body surface reference position data, which is reference position image data, can also be acquired when the treatment plan CT image is acquired in step 2. In that case, since it can be matched with the body surface reference position data at the time of treatment planning in all steps downstream from the treatment plan, it is more desirable in terms of reproducibility.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described. In the first embodiment described above, the two-dimensional image data is used only for extracting the feature region, and only the three-dimensional position data is used for collation between the body surface measurement position data and the body surface reference position data. . As another alternative, information related to two-dimensional image characteristics such as color and luminance on the body surface in the two-dimensional image data can be used for collation. Examples of the two-dimensional image feature include a mole, aza, or two-dimensional image information of a body contour. Alternatively, there is a method of attaching a marker to the body surface in advance. Considering very roughly, the human trunk can be seen as a cylinder. In the cylinder, there is no three-dimensional feature in the body axis direction except for the end portion, and therefore positioning in this direction cannot be performed only with the three-dimensional body surface information. Since the human trunk is not a cylinder at all, positioning in the direction of the body axis is possible by using a delicate curved surface on the surface of the body, but the convergence of calculations can be achieved by using it together with two-dimensional image information. As a result, calculation time can be shortened and positioning accuracy can be improved.

Embodiment 5. FIG.
The fifth embodiment of the present invention will be described below with reference to FIGS. FIG. 8 is an equipment layout diagram of a CT apparatus (gantry) 39 used for tomography and treatment planning before treatment with radiation or particle beams equipped with a two-dimensional and three-dimensional optical measurement device including a pattern light source 11 and a video camera 14. It is. Since the CT apparatus 39 is not an apparatus that performs actual treatment like the particle beam treatment apparatus, it does not include an irradiation step. The CT apparatus 39 is an apparatus used for tomography at the time of examination and treatment planning. When repeating the above, the reproducibility of the positioning of the patient is necessary. FIG. 9 shows a tomographic image taken by the CT apparatus 39 and a patient's body surface measured by a three-dimensional optical measurement apparatus, acquires position data, compares it with reference position data, and sets the patient to a position where irradiation is possible. It is explanatory drawing which shows the result of having implemented the treatment plan and calculated | required dose distribution. In FIG. 8, 9a is an X-ray tube for CT, 9b is an X-ray detector (for CT), 43 is the center of the trunk of the CT image, and 44a is an irradiation field central body surface projection obtained by projecting the irradiation field center in the vertical direction. Points (V) and 44b are irradiation field central body surface projection points (H) obtained by projecting the irradiation field center in the horizontal direction. Reference numeral 41 denotes a patient's moving base, and 41a denotes a moving base top.

  Next, the operation will be described. At the time of tomography and treatment planning, the patient's body surface is measured using the two-dimensional and three-dimensional optical measurement devices shown in FIG. 8, and position data of the body surface is acquired. The acquired 3D position data is used as the body surface reference position data, and the 3D position data acquired during the treatment plan is always compared with the body surface reference position data to keep the patient position and posture at a predetermined position and posture. Yes. The operations for measuring and collating the two-dimensional image data and the three-dimensional position data are the same as those in the first embodiment. In this CT apparatus 39, the initial patient position data is used as the body surface reference position data, and the initial patient position is reproduced next time, and the position data taken at the time of positioning when performing an examination is used as the body surface measurement position data as an image. The data is taken into the processing computer 27 side, both data are compared and collated, the difference is calculated, the adjustment amount is obtained and adjusted, and positioning is performed.

  9A, 9 </ b> B, and 9 </ b> C are a transverse tomographic image, a body axis horizontal tomographic image, and a body axis vertical tomographic image including the affected part by the CT apparatus 39. After the contour and the center position are determined, adjustment is performed by moving the affected part in a predetermined position and direction. (D) compares and collates body surface measurement position data, which is three-dimensional position data of the body surface measured using a two-dimensional and three-dimensional optical measurement device, with body surface reference position data, and a reference position (reference body position 2e). It is a figure which shows the body surface before moving to. (E) compares the body surface measurement position data, which is the 3D position data of the body surface measured using a 2D and 3D optical measurement device, with the body surface reference position data, and sets the patient as the reference position. And it is a figure which shows the result of having calculated dose distribution with the treatment plan CT apparatus, and the code | symbol 6a has shown the isodose distribution figure in an irradiation field.

  In this way, information necessary for patient positioning necessary at the time of particle beam treatment can be set on the monitor screen of the treatment planning apparatus. As described above, tomography of a patient undergoing particle beam therapy and positioning of a treatment plan can be performed with high positional accuracy, and at the same time, the position of the patient at the time of diagnosis and treatment planning by CT image can be monitored. Control to hold in a predetermined position can be easily performed. FIG. 8F is a diagram showing a conventional method in which a plurality of affected part position display markers 50a to 50d and 50f are attached to the patient's body surface.

Embodiment 6 FIG.
The sixth embodiment of the present invention will be described below with reference to FIG. FIG. 10 is an apparatus configuration diagram of an X-ray simulator 40 equipped with a two-dimensional and three-dimensional optical measuring device as a patient positioning measuring means. The X-ray simulator 40 is a stage before treatment with radiation or particle beams. This is a device for confirming the position, direction, size, shape, and irradiation direction of an irradiation field simulating treatment based on a treatment plan result. Measure the patient's body surface with a 2D and 3D optical measurement device, acquire 2D image data and 3D position data, compare and compare with 3D body surface reference position data, and position the patient at an irradiable position. The patient positioning to be set is performed in the same manner as in the first embodiment.
In FIG. 10, 5c is an isocenter (SM), 9d is an X-ray detector (SM) for digital radiography, 40a is an X-ray multi-leaf collimator, 41b is a support leg of the movable frame 41, and 41c is a movable frame top plate. Each is shown.

  Next, the operation will be described. In FIG. 10, the pattern light emitted from the pattern light source 11 at the time of simulation is irradiated on the body surface of the patient 2, and the reflected light from the patient body surface is measured by the video camera 14, and 2D image data and 3D position data are measured. To get. The method of comparison and collation between the acquired three-dimensional body surface measurement position data and body surface reference position data is the same as in the first embodiment. Using the comparison result, the patient 2 is moved to the position and posture where the treatment irradiation to the patient 2 can be simulated with X-rays using the movable frame 41. FIG. 11A is an image obtained by extracting the body contour 2d and the body surface feature patterns 46, 47, and 48 based on the two-dimensional image data projected to the video camera 14 in the scanning pattern light irradiation field 13b. .

  (B) in FIG. 11 compares and collates position data (body surface reference position data and body surface measurement position data) corresponding to the feature patterns 46 and 47 in the three-dimensional position data acquired in (A). It is explanatory drawing showing the body surface shape (body outline 2d, the body surface characteristic pattern 46, 47, 48, etc.) when the patient 2 is moved to the position and posture which can perform X-ray simulation using the moving stand 41. (C) in FIG. 11 is a cross-sectional image of the affected area of the patient and the surrounding area where the X-ray simulation was performed with the patient 2 set to the reference position. 42b shows a double irradiation X-ray irradiation field when the X-ray is focused on the necessary irradiation field and double irradiation is performed in a state where the patient is at the reference position during the X-ray simulation. In the figure, reference numeral 42a denotes an X-ray irradiation field.

  In this way, the position, shape, size, and direction of the irradiation field necessary for the treatment can be confirmed, and the position and posture data of the patient 2 can be acquired and confirmed in parallel. The above operations can be performed while confirming the positioning of the patient 2 only on the monitor screen without using the position marker. As described above, positioning during X-ray simulation of a patient receiving particle beam therapy can be performed non-invasively and with high accuracy.

Embodiment 7 FIG.
In the first embodiment described above, the pattern light source 11 of the three-dimensional optical measurement device and the video camera 14 are integrated and attached to the rotating irradiation head 1, and the pattern light source is independent of the rotation angle of the irradiation head 1. The distance between the camera 11 and the video camera 14 is constant, and the body surface of the patient 2 is measured and positioned. However, the pattern light source 11 and the video camera 14 are not necessarily mounted on the irradiation head 1. For example, the pattern light source 11 and the video camera 14 of the three-dimensional optical measurement device may be mounted on a fixed side such as a side wall of a treatment room.

  FIG. 12 is an equipment layout diagram showing a treatment irradiation system in which the pattern light source 11 and the video camera 14 of the three-dimensional light measurement apparatus are installed on the side wall of the treatment room. 2A is a front view showing the video monitor 15 removed from FIG. 1B, FIG. 2B is a side view of FIG. 1A, and a top view of the patient 2 on the treatment table 3 observed from above. In the arrangement of the pattern light source 11 and the video camera 14, the body surface feature pattern is the body surface feature pattern 48b shown in FIG. A line indicated by reference numeral 48b is an outline of the base portion of the leg, for example, which can be observed from the body side.

  The method for collating the three-dimensional position data of the body surface reference position data and the body surface measurement position data is the same as in the first embodiment. The treatment irradiation system can automatically set the patient on the treatment table 3 with the center of the affected area in the vicinity of the center of the irradiation field. FIG. 13A shows the state before positioning, and FIG. 13B shows the state at the time of positioning. In this way, patient positioning can be performed independently of the rotation of the irradiation head 1. As described above, the positioning of the patient 2 receiving the particle beam therapy is relatively simple control, and the patient can be positioned with high positional accuracy without being invasive, and the patient's posture holding and posture confirmation during the rotation irradiation are continuously performed. Can be done.

Embodiment 8 FIG.
In addition to the method described in the first embodiment, there are the following methods as data collating means for comparing and collating body surface reference position data and body surface measurement position data. That is, as a means for collating three-dimensional measurement data measured at different positions, regarding the three-dimensional position data at a plurality of positions on the body surface, the position data that are closest to each other are provisionally associated with each other, and the provisional position Processing is performed so that the processing for obtaining the posture conversion parameters is performed gradually. Furthermore, in the verification means for obtaining the final position / orientation conversion parameter, the position deviation between corresponding points after conversion using the temporary attitude conversion parameter is statistically determined to be significantly larger than the position deviation of the entire corresponding point group. And the temporary posture conversion parameter is obtained again, and the treatment table 3 and the treatment table top plate 3a are moved and rotated by this parameter.

In this way, the treatment irradiation system can automatically set the patient 2 on the treatment table 3 with the center of the affected part 2a in the vicinity of the center of the irradiation field. By using in combination with the positioning method described in the first embodiment, an effect that high-precision positioning can be performed at high speed can be obtained. Further, by correcting using the whole data, positioning reproducibility can be ensured even when there is a non-rigid posture change.
It should be noted that this collation method can also be used when the body position is corrected at a site other than the periphery of the affected area (arm, head and neck, etc.) before the affected area is positioned as in the second embodiment. Thus, by obtaining the temporary posture conversion parameter after removing the singular point of the position deviation, it is possible to improve the positioning accuracy of the patient.

It is a layout view showing an irradiation head, a treatment table, and a patient of the particle beam therapy system according to Embodiment 1 of the present invention. It is a system block diagram which shows the particle beam accelerator of the particle beam therapy apparatus in Embodiment 1, an irradiation head, a treatment table, those control apparatuses, and a patient. 2 is a system block diagram of a two-dimensional and three-dimensional optical measurement device mounted on an irradiation head of the particle beam therapy system according to Embodiment 1. FIG. It is a figure which shows the timing chart of the optical measurement using a two-dimensional and a three-dimensional optical measuring device. It is an equipment layout when positioning a patient using a two-dimensional and a three-dimensional optical measuring device. It is Embodiment 1, and is explanatory drawing which specializes the characteristic area | region of a patient body surface and positions a patient using a three-dimensional optical measuring device. It is a flowchart which shows the flow of the patient positioning operation in radiation therapy or particle beam therapy in embodiment. FIG. 10 is a device arrangement diagram of a CT apparatus used for tomography and a treatment plan before the treatment with radiation or particle beam, which is a fifth embodiment, mounted with a two-dimensional and three-dimensional optical measurement device. It is Embodiment 5, Comprising: It is explanatory drawing which adjusts a patient to the position which can be irradiated with a treatment plan CT apparatus, implements a treatment plan, and calculates | requires dose distribution.

FIG. 10 is a layout diagram of an X-ray simulator according to Embodiment 6 in which a two-dimensional and three-dimensional optical measurement device is mounted as a patient positioning unit. In the sixth embodiment, the body surface measurement position data measured using the two-dimensional and three-dimensional optical measurement devices are compared with the body surface reference position data, the patient is adjusted to the reference position, and the X-ray simulation is performed. It is explanatory drawing implemented. FIG. 10 is a layout view of a treatment irradiation system according to a seventh embodiment in which a pattern light source and a video camera of a two-dimensional and three-dimensional optical measurement device are installed on a side wall of a treatment room. FIG. 18 is an explanatory diagram of Embodiment 7, in which body surface measurement position data measured using a three-dimensional optical measurement device and body surface reference position data are compared and collated, and a patient is adjusted to a reference position. FIG. 2 is a layout view of a positioning apparatus for a patient in radiation therapy or particle beam therapy in the related art. It is explanatory drawing for positioning a patient conventionally. It is a flowchart which shows the flow of the positioning operation of the patient in the conventional radiotherapy or particle beam therapy.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Irradiation head 2 Patient 2a Affected part 2b Affected part outline 2c Affected part center 2d Body surface shape (body outline)
2e Reference position 3 Treatment table (patient support table)
3a Treatment table top plate (patient support table top plate) 3b, 41b Support leg 4, 4a X-ray detector 5 Rotation drive mechanism 5a Rotating shaft 5b Isocenter 5c Isocenter (SM) 6 Particle beam 6a Isodose distribution diagram (irradiation field) 7 Bending Electromagnet 8 Scatterer 9 X-ray Tube 9a CT X-ray Tube 9b X-ray Detector (for CT)
9d X-ray detector (SM) 10 Multi-leaf collimator 11 Pattern light source 11a Pattern light source controller 12a Uniform pattern light (environment light) 13a Scan pattern light 13b Scan pattern light irradiation field 13c Reflection pattern light 14 Video camera 15 Video monitor 16 Keyboard 17 Light Localizer 17a Light Localizer Crosshair 17b Light Localizer Crosshair 18 Laser Pointer 20 Particle Beam Accelerator 21 Beam Transport System 22 Accelerator Controller 23 Rotation Controller 24 Irradiation Head Controller 25 Treatment Table Controller 26 Signal Processor 27 Image Processing Computer 28 Accelerator control computer 29 Irradiation system control computer 31 Laser modulation circuit 32 Laser light source 33 Modulated laser light 35 Pattern light 36 Scanner mirror 37 Mirror drive circuit 38 Driver 39 T unit (gantry) 40 X-ray simulator 40a X-ray multileaf collimator 41 moving platform 41a, 41c moving platform top plate 42a X-ray irradiation field 42b 2 double X-ray irradiation field 43 trunk center (CT image)
44a Irradiation field central body surface projection point (V) 44b Irradiation field central body surface projection point (H)
46, 47, 48, 48b Characteristic pattern 48a Arm pattern 49a Body surface affected part center point (H) 49b Body surface affected part center point (V)
50a, 50b, 50c, 50d, 50e, 50f Body surface position marker

Claims (3)

  The reflected light reflected from the patient's body surface on the patient support table is measured by two-dimensional measurement and three-dimensional measurement using measurement light and a camera, and two-dimensional image data and three-dimensional position data serving as position data are obtained. The body surface reference position data obtained in advance by the body surface shape measurement means and the body surface shape measurement means and the patient body surface measurement position data obtained by the body surface shape measurement means at the time of measurement are compared and collated. A data collating means for calculating the difference, and a position adjusting means for inputting the output information of the data collating means and moving the patient support table in a direction in which the difference falls within an allowable range for positioning. Using the shape measurement means, measure the body posture state in the part other than the peripheral part of the affected area of the patient, obtain measurement posture data, in the data collation means, the measurement posture data, Compared collating the site of the surface reference position data corresponding to the record, the positioning device characterized by determining the difference. An image processing computer is provided in the data collating means, and the image processing computer has an object of setting the difference within an allowable range based on the difference between the measurement body position data and the body surface reference position data of the corresponding part. The positioning device according to claim 1, wherein an adjustment amount of the same part is calculated as follows. The said data collating means has a database for specifying site | parts other than the affected part periphery part used as the measuring object of the said measurement posture data according to a treatment site | part, The Claim 1 or Claim 2 characterized by the above-mentioned. Positioning device.

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