JP5698452B2 - X-ray CT apparatus, implant operation support device, and implant operation support program - Google Patents

Description

  The present invention relates to an X-ray CT apparatus (computer tomography apparatus), and more particularly to an X-ray CT apparatus that supports dental implant treatment, an implant treatment support device, and an implant treatment support program.

  Conventionally, an X-ray CT apparatus is used as a medical image diagnostic apparatus. An X-ray CT apparatus collects projection data by exposing X-rays to a patient, and detecting X-rays transmitted through the patient with an X-ray detector, and acquires a tomographic image of the patient by reconstruction. Can do.

  In addition, dental implants are used as a method of planting dentures reliably and firmly in a missing part of a tooth during dental treatment. Implants are used to correct teeth and treat missing teeth. However, there are areas around the teeth that should not erode anatomically, such as nerves and blood vessels. Need to be determined accurately.

  Conventionally, in implant treatment, a doctor performs interpretation based on an image of a tooth region photographed by an X-ray CT apparatus, grasps the position of a nerve, the position of a blood vessel, etc., and manually performs marking. In addition, information such as bone density and bone position around the teeth is acquired from the imaging results and used as a reference when performing implant treatment. For example, the positional relationship between bones and nerves is grasped from the photographed image, a part having a high bone density is searched, the implanting position and angle of the implant are examined, and the protrusion is not protruded after implantation.

  However, in the above-described method, the result greatly varies depending on the interpretation technique of the doctor, the burden on the doctor is large, and the knowledge and know-how of the individual doctor are important.

  Patent Document 1 discloses an image diagnostic apparatus that generates and displays a tomographic image of a subject's teeth from a continuous slice image obtained by X-ray imaging. In this example, a panoramic curve is drawn on a tomographic image, and a panoramic tomographic image is generated from a continuous slice image and displayed. However, the example of Patent Document 1 is insufficient to support the implant operation, and cannot accurately support the position and direction of implanting the implant.

Japanese Patent No. 362146

  Conventionally, in implant treatment, a doctor interprets an image based on an image of a tooth region photographed with an X-ray CT apparatus, grasps the positional relationship between bones and nerves from the photographed image, and searches for a portion having a high bone density. However, there was a problem that the result greatly changed depending on the doctor's interpretation technique and the burden on the doctor was increased.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an X-ray CT apparatus capable of displaying a support image for supporting an implant operation, an implant operation support apparatus, and an implant operation support program.

The X-ray CT apparatus according to the first aspect of the present invention includes an imaging unit that irradiates a subject with X-rays and collects a tomographic image of the subject, and imaging by the imaging unit in order to set an implant placement position. An extraction unit that extracts a portion that should not be eroded anatomically from the image and a portion whose bone density is higher than a preset value, and implant placement based on information on the portion extracted by the extraction unit A calculation unit that calculates a position and an implant image that indicates an implantation position of the implant are superimposed on the captured image, and the bone density extracted by the extraction unit to support implant operation is higher than a preset value An image generation unit that generates a support image including an image in which a region is colored according to bone density, and a display unit that displays the support image generated by the image generation unit are provided.

Furthermore, in the implant operation support device according to the present invention according to claim 8, in order to set the implantation position of the implant, a site that should not be eroded anatomically from the image obtained by imaging the subject, and a bone density are set in advance. An extraction unit for extracting a portion higher than the calculated value, a calculation unit for calculating the implantation position of the implant based on the information of the region extracted by the extraction unit, and an implant image indicating the implantation position of the implant Generation of a support image including an image in which a portion where the bone density extracted by the extraction unit is higher than a preset value is colored according to the bone density is superimposed on the captured image And a display unit for displaying the support image generated by the image generation unit.

Furthermore, the support program for implant operation according to the present invention according to claim 9 is a program for supporting implant operation, and in order to set the implantation position of the implant in a computer, an anatomy is obtained from an image obtained by photographing the subject. The extraction position for extracting parts that should not be eroded and the part whose bone density is higher than a preset value, and the position of the implant is calculated based on the information of the part extracted by the extraction function and calculating function, the implant image for instructing the implantation position of the implant superimposed on the captured image, depending on the bone density higher portion than the value which the bone density is preset that issued because extracted with supporting implant operation It is characterized and an image generating function of generating an assist image including the images colored, that to realize a display function of displaying the help image Te .

  According to the present invention, it is possible to display a support image that supports an implant operation as a planar image or a stereoscopic image, and to display a site that should not be anatomically eroded and strength such as bone density. Therefore, it is possible to support the implant operation and reduce the time required for implant placement.

1 is a block diagram showing a configuration of an X-ray CT apparatus according to an embodiment of the present invention. The flowchart explaining operation | movement of the X-ray CT apparatus which concerns on embodiment. Explanatory drawing which shows an example of the display image which assists implant treatment. Explanatory drawing which shows the other example of a display image. Explanatory drawing which shows the further another example of a display image. Explanatory drawing which shows an example of a 3D display image.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of an X-ray CT apparatus (computer tomography apparatus) according to an embodiment of the present invention. The X-ray CT apparatus 100 includes a gantry 10 and a computer system 20. The gantry 10 collects projection data related to a patient (subject) P, and includes a rotating frame 11, an X-ray tube 12, an X-ray detector 13, a data collecting unit 14, a non-contact type data transmission device 15, a slip A ring 16 and a gantry drive unit 17 are included. The X-ray tube 12, the X-ray detector 13, and the data collection unit 14 constitute an imaging unit that collects a tomographic image of a patient.

  The rotating frame 11 is a ring that is driven to rotate, and is mounted with an X-ray tube 12 and an X-ray detector 13. The central portion of the rotating frame 11 is open, and the patient P placed on the couch top 18 is inserted into the opening. The X-ray tube 12 is a vacuum tube that generates X-rays. Electric power (tube current and tube voltage) necessary for X-ray exposure is supplied to the X-ray tube 12 from a high voltage generator 28 (described later). It is supplied via a slip ring 16. The X-ray tube 12 exposes X-rays to the patient P placed in the effective visual field region FOV by accelerating electrons by the supplied high voltage and colliding with the target.

  The X-ray detector 13 detects X-rays transmitted through the patient P, and is attached to the rotating frame 11 so as to face the X-ray tube 12. The X-ray detector 13 is, for example, a multi-slice type detector, and a plurality of detection elements configured by combining a scintillator and a photodiode are two-dimensionally arranged.

  The data acquisition unit 14 is called DAS (Data Acquisition System), converts a signal output from the X-ray detector 13 for each channel into a voltage signal, amplifies it, and further converts it into a digital signal. This digital data is sent to the computer system 20 via the non-contact type data transmission device 15. The gantry driving unit 17 drives the rotary frame 11 to rotate. By this rotation driving, the X-ray tube 12 and the X-ray detector 13 are rotated in a spiral manner around the body axis of the patient P while facing each other.

  The computer system 20 includes a bus line 201, and includes a preprocessing unit 21, a system control unit 22, a storage unit 23, a reconstruction processing unit 24, an image processing unit 25, a display unit 26, an operation unit 27, and a high voltage generation unit 28. I have. The preprocessing unit 21 receives the raw data from the data collection unit 14 via the non-contact data transmission device 15 and performs sensitivity correction and X-ray intensity correction.

  The system control unit 22 is connected to the bus line 201. The system control unit 22 includes a CPU 221 and performs overall control of the X-ray CT apparatus 100 according to a program stored in the ROM, and performs scan processing image generation processing, image display processing, and the like.

  The raw data subjected to various corrections by the preprocessing unit 21 is called projection data and is temporarily stored in the storage unit 23 via the bus line 201. The reconstruction processing unit 24 is equipped with a plurality of kinds of reconstruction methods, and reconstructs image data by the reconstruction method selected by the operator.

  The image processing unit 25 performs image processing for display such as window conversion and RGB processing on the reconstructed image data generated by the reconstruction processing unit 24, and outputs the image processing to the display unit 26. Further, the image processing unit 25 displays a support image for supporting the implant operation on the display unit 26 under the control of the system control unit 22.

  The implant information is programmed in advance, and allows the user to select the shape, number, size, etc. of the implant, and displays an image of the selected implant on the screen. The implant image is displayed together with an image obtained by photographing the patient. Therefore, the image processing unit 25 generates a tomographic image of an arbitrary cross section, a projection image from an arbitrary direction, a three-dimensional image, and the like based on an instruction from the operator and outputs the generated image to the display unit 26.

  In addition, when displaying the implant image, the image processing unit 25 extracts parts such as blood vessels, nerves, and sinuses that should not be anatomically eroded. In addition, the photographed bone part is extracted, and the bone density (bone strength) is calculated. Furthermore, an implant placement position is calculated based on the extracted part information, and an implant image that indicates the implant placement position is generated. In addition, a support image for assisting the implant operation is generated by superimposing the implant image on the photographed image.

  The storage unit 23 stores image data such as reconstructed tomographic image data in addition to raw data. The display unit 26 displays a CT image such as a computer tomographic image input from the image processing unit 25 and a support image that supports the implant operation. The operation unit 27 includes a keyboard, various switches, a mouse, and the like, and is operated by an operator (operator) to input various scan conditions and the like. In addition, when an implant is placed, an implant is selected or an implant position is corrected.

  The high voltage generator 28 supplies power necessary for X-ray exposure to the X-ray tube 12 via the slip ring 16. The X-ray CT apparatus 100 communicates with other apparatuses such as an RIS (Radiology Information System) server and PACS (not shown) via a network, and transmits image data and patient data to the PACS via the network. Information etc. can also be saved.

  Furthermore, the system control unit 22 determines the feed amount, feed speed, X-ray tube 12 and X-ray tube 12 in the body axis direction of the high voltage generation unit 28, the gantry drive unit 17 and the top plate 19 based on the input scanning conditions. The rotational speed, rotational pitch, and X-ray exposure timing of the line detector 13 are controlled, and an X-ray cone beam or X-ray fan beam is exposed from multiple directions to a desired imaging region of the patient. Data collection (scanning) processing of the line CT image is performed.

  Hereinafter, an image display process that supports the implant operation, which is a feature of the present invention, will be described. In the following description, implant placement in dental treatment will be described as an example. FIG. 2 is a flowchart showing the operation of the X-ray CT apparatus 100, and mainly shows the operation of the image processing unit 25.

  In FIG. 2, in step S <b> 1, a region around a patient (subject) tooth is imaged. In step S2, when displaying the photographed image, a location such as a blood vessel, a nerve, or a sinus that is a portion that should not be eroded anatomically is extracted. Sites such as blood vessels, nerves, and sinuses are extracted based on CT values.

  Next, in step S3, bone density (bone strength) is calculated based on the photographed image. The bone density is estimated from the CT value of the photographed image, and a region where the bone density is higher than a preset value is extracted. In step S4, images of nerves, blood vessels and bones extracted in steps S2 and S3 are displayed. For example, an image of the patient's lower jaw or upper jaw viewed from above (below), an image viewed from the side, and an image viewed from the front are displayed. These images are so-called planar images viewed from three directions corresponding to a plan view, a side view, and a front view. In addition to the three-direction image, a 3D image is displayed to see the entire lower jaw and upper jaw.

  In addition, in order to distinguish between high bone density parts and low bone density parts, the parts with high bone density are colored in warm colors, and the parts with low bone density are colored in cold colors. Apply. Similarly, the nerve and blood vessel portions are also displayed in different colors so that they can be easily seen visually.

  In step S5, implant information is input. In this step S5, implant information is programmed in advance so that a user (doctor, engineer, etc.) can select implant information such as the shape, number, and size of the implant.

  In step S6, the implantation position, implantation direction, implantation depth, and the like of the implant are calculated, and an implant image instructing the implantation of the implant is displayed on the photographed image. That is, based on the anatomically eroded portion information calculated in steps S2 and S3, the bone density value, and the implant information (shape, number, size, etc.), the position, direction, Determine the embedding depth. In step S6, an implant image is displayed, and an optimal position of the implant is displayed.

  As the implant placement position, for example, a portion separated by about 3 mm from a portion that should not be eroded anatomically is listed as a candidate. Next, in consideration of the location and angle where the implant does not pop out when the implant is inserted, the position with the highest bone density is calculated and displayed.

  In addition, when two or more implants are selected, conditions such as the minimum gap between the actual tooth and the implant and the minimum gap between the implants are also automatically set to implant the implant. The placement position is determined in consideration of the situation. Further, after determining the implant position, the operator can manually operate the implant displayed on the screen so that the operator can correct the implant position.

  As described above, the image processing unit 25 extracts the parts such as blood vessels, nerves, and sinuses that should not be eroded anatomically, and bone parts, and implant implants based on the extracted part information. It functions as a calculation unit that calculates the entry position and an image generation unit that generates a support image that supports the implant operation by superimposing the implant image on the captured image.

  Hereinafter, with reference to FIG. 3 to FIG. 6, a support image for supporting the implant operation will be described.

  FIG. 3 is an image of the lower jaw portion of the patient as viewed from above, and includes a bone portion 31 such as the lower jaw, a tooth 32, and a blood vessel / nerve portion 33. The blood vessel / nerve portion 33 is displayed in a color (for example, red) that can be distinguished from the bone portion 31 and the tooth 32 to clearly indicate that the portion should not be eroded anatomically. Further, as shown in the legend 40, the bone portion 31 is hierarchically colored so that a portion with a high bone density is displayed in a color with a warm color system 41 and a portion with a low bone density is displayed in a color with a cool color system 42 (note that In the figure, coloring is omitted).

  In FIG. 3, the implant 34 is assumed to be embedded in a missing tooth 321 portion, for example, and is displayed so that the insertion position 35 can be clearly seen. Since the information of the implant 34 is programmed in advance, the shape, number, size, etc. are selected by the user, and the shape of the selected implant 34 is displayed on the screen. In order to select an implant, images imitating various implants are displayed on the screen and are selected by operating the operation unit 27.

  FIG. 4 is an image of the lower jaw viewed from the side. In the image seen from the side, the implantation position and the implantation direction (angle α) of the implant 34 are known. The hatched portion in FIG. 4 is a portion with high bone density. In order to prevent the blood vessel / nerve portion 33 from eroding when the implant 34 is placed, the interval between the tip of the implant 34 and the blood vessel / nerve portion 33 is displayed as a candidate for placement, for example, at a distance of 3 mm or more. In FIG. 4, an image such as a numerical value indicating the depth of implantation 34, the implantation angle α, and the bone thickness may be displayed at the same time.

  FIG. 5 is an image of the lower jaw viewed from the front. FIG. 5 shows that there is a missing tooth 321 in the right part of the lower jaw, and the position and direction of implantation of the implant 34. Further, the position of the blood vessel / nerve portion 33 is also known. In this way, by displaying three planar images viewed from a plurality of angular directions, the user can accurately grasp the implantation position and implantation direction of the implant 34.

  FIG. 6 is a 3D image in which the entire lower jaw is displayed three-dimensionally. By displaying a 3D image in addition to the three planar images, the implantation position of the implant 34 can be displayed more clearly, and the positional relationship between the blood vessel / nerve portion 33 and the implant 34 can be clearly understood. .

  3 to 6 are candidates calculated by the CPU 221 and the image processing unit 25, and can be corrected by the user. In this case, the displayed image of the implant 34 is corrected by a manual operation, and the corrected image of the implant 34 is displayed.

  In the case of correction, the position of the blood vessel / nerve portion 33 and the bone density are displayed in a form that can be visually distinguished by color, so the distance from the portion that should not be eroded anatomically and the bone is thin. It can be corrected in consideration of the location and angle where the implant does not pop out too much.

  In addition, when two or more implants 34 are placed, the minimum interval between the implant 34 and the actual tooth and the minimum interval between the implants are automatically added and displayed. Is done.

  Any one of the images shown in FIGS. 3 to 6 can be selectively displayed, but any image may be simultaneously displayed on one screen. Moreover, although the example of a display of the captured image of the lower jaw part was given, you may display the image of an upper jaw part. In this case, it is preferable to display an image of the upper jaw portion viewed from below or a stereoscopic image viewed from below.

  As described above, in the embodiment of the present invention, an image supporting the implant operation can be displayed as a planar image or a three-dimensional image, and a site that should not be anatomically eroded and a strength such as bone density are displayed. Therefore, the implant operation can be supported, and the time required for implant placement can be reduced.

  In the above description, an example in which an image captured by an X-ray CT apparatus is processed has been described. However, an X-ray imaging apparatus dedicated to dental treatment that performs partial CT imaging may be used. Various modifications can be made without departing from the scope of the claims.

DESCRIPTION OF SYMBOLS 100 ... X-ray CT apparatus 10 ... Base 11 ... Rotating frame 12 ... X-ray tube 13 ... X-ray detector 14 ... Data collection part 15 ... Data transmission apparatus 16 ... Slip ring 17 ... Base drive part 18 ... Bed 20 ... Computer System 21 ... Pre-processing unit 22 ... System control unit 221 ... CPU
DESCRIPTION OF SYMBOLS 23 ... Memory | storage part 24 ... Reconstruction process part 25 ... Image processing part 26 ... Display part 27 ... Operation part 28 ... High voltage generation part 31 ... Bone partial image 32 ... Tooth image 33 ... Blood vessel / nerve image 34 ... Implant image

Claims (9)

An imaging unit that irradiates the subject with X-rays and collects tomographic images of the subject;
In order to set the implantation position of the implant, an extraction unit that extracts a portion that should not be eroded anatomically from the image captured by the imaging unit, and a region where the bone density is higher than a preset value;
A calculation unit that calculates the implantation position of the implant based on the information of the site extracted by the extraction unit;
An implant image indicating the implant position is superimposed on the captured image, and a portion where the bone density extracted by the extraction unit is higher than a preset value is colored according to the bone density in order to support the implant operation. an image generator for generating an assistant image including the images,
A display unit for displaying the support image generated by the image generation unit;
An X-ray CT apparatus comprising:   The X-ray CT apparatus according to claim 1, wherein the image generation unit generates a planar image or a stereoscopic image when the affected part is viewed from a plurality of angular directions as the support image.   The X-ray CT apparatus according to claim 1, wherein the image generation unit generates an image indicating an embedding direction and an embedding depth at the implanting position as the implant image. The image generation section, X-rays CT apparatus according to claim 1, wherein generating a hierarchical colored display image with the bone density.   The X-ray CT apparatus according to claim 1, wherein the calculation unit calculates an implantation position of the implant based on information including a shape, a number, and a size of the implant.   The X-ray CT apparatus according to claim 1, wherein the implant image displayed on the display unit can be corrected by a user operation. The calculation unit selects a candidate for the implantation position of the implant according to a position where the bone density should not be eroded anatomically and a position where the bone density is higher than a preset value. The X-ray CT apparatus according to claim 1, wherein a position with the highest bone density is calculated as an implantation position from the above. In order to set the implantation position of the implant, an extraction unit that extracts a portion that should not be anatomically eroded from an image obtained by imaging the subject, and a portion where the bone density is higher than a preset value;
A calculation unit that calculates the implantation position of the implant based on the information of the site extracted by the extraction unit;
An implant image indicating the implant position is superimposed on the captured image, and a portion where the bone density extracted by the extraction unit is higher than a preset value is colored according to the bone density in order to support the implant operation. an image generator for generating an assistant image including the images,
A display unit for displaying a support image generated by the image generation unit; A program that supports the implant procedure,
In order to set the implantation position of the implant, an extraction function for extracting a portion that should not be anatomically eroded from an image obtained by imaging the subject, and a portion where the bone density is higher than a preset value;
A calculation function for calculating the implantation position of the implant based on the information of the site extracted by the extraction function;
Superimposing the implant image for instructing the implantation position of the implant in the captured image, an image higher portion than the value which the bone density is preset that issued because extracted with supporting implant operation was colored in accordance with the bone density An image generation function for generating a support image including
A display function for displaying the support image;
Support program for implant treatment to realize

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