JP2012135411A - Method and apparatus for designing artificial bone for skull bone filling, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an artificial bone which can be accurately filled into a void as an area produced by skin atrophy or excision of the brain.SOLUTION: An artificial bone outer shape data acquisition part 22 acquires artificial bone outer shape data 31 corresponding to a defective part 101a of the skull bone 101. A skin shape data acquisition part 23 acquires skin shape data 32 of the skin surface at a skin part 103 based on a part of pixel density corresponding to the skin part 103 in a cross section image of the head part 100. An artificial bone inner face shape data forming part 24 forms artificial bone inner face shape data 33 of an inside face of the artificial bone in accordance with the shape of the skin surface on the surface of the defective part 101a based on the skin shape data 32. An artificial bone thickness data forming part 25 forms thickness data 34 of the artificial bone to fill up between the outer shape of the artificial bone and the inside face of the artificial bone based on the artificial bone outer shape data 31 and the artificial bone inner face shape data 33.

Description

  The present invention relates to a method for designing a skull-complementing artificial bone, a device for designing a skull-complementing artificial bone, and a program for designing an artificial bone that compensates for a defect in the skull.

  2. Description of the Related Art Conventionally, an artificial bone that compensates for a defect in a skull when a defect occurs in the skull when a part of the skull is lost or removed due to treatment of an accident or disease has been used. As a design method or design system for designing an artificial bone that fills a defect in such a skull, one disclosed in Patent Document 1 or Patent Document 2 is known.

  In the design method disclosed in Patent Document 1, first, three-dimensional data of the skull is created based on a plurality of tomographic data of the skull. Then, in the three-dimensional data, a half body having a missing portion and a half body not having the missing portion obtained when divided on a symmetry plane are hypothesized. Furthermore, by extracting a part that does not overlap with the half that has the defect when the half that does not have the defect is inverted to a plane-symmetrical position with the symmetry plane as the center, an artificial part corresponding to the defect is extracted. The outline of the bone is determined. Further, the thickness of the artificial bone is estimated based on the thickness of the half body having no defect. And using at least one of the shape data of the soft tissue near the defect part and the shape data of the soft tissue near the part of the half that does not have the defect part and is located symmetrically with the defect part Then, correction is performed such as increasing or decreasing the thickness of the artificial bone.

  In the design system disclosed in Patent Document 2, first, in each of the tomographic images at a plurality of tomographic positions in the head, a pixel region having a predetermined density level is extracted as a bone part candidate region of the skull, The bone area candidate area having the largest area is selected as the confirmed bone area. Then, bone outline information that is outline information of an area to be finally determined as a bone part is generated using only the outline that faces the outer surface of the human body in the determined bone area. Furthermore, three-dimensional shape data of the defect portion of the skull is generated based on the bone outline information for each tomographic position. If the missing part exists only on one side of the skull divided into right and left, the three-dimensional shape data of the missing part is generated so that the missing part is restored by mirror image copy.

JP 2005-160646 A JP 2001-92950 A

  When a defect occurs in the skull due to a partial defect or excision of the skull, an artificial bone designed by the method or system disclosed in Patent Document 1 or Patent Document 2 is supplemented. . When the artificial bone is filled in the defect, a void as a region caused by skin atrophy or brain resection is likely to occur inside the artificial bone as a dead space. The occurrence of such dead spaces can increase the risk of infection.

  In the design method disclosed in Patent Document 1, the thickness of the artificial bone is estimated based on the thickness of the portion of the skull where there is no defect, and the soft tissue near the defect or the portion symmetrical to the defect Using the shape data of the soft tissue in the vicinity of, correction such as thickening or thinning is performed. For this reason, the design method of Patent Document 1 is a method that only corrects to increase or decrease the thickness of the artificial bone, so that an artificial space that can accurately fill a void as a region caused by skin atrophy or brain resection is possible. It is difficult to form a bone, and there is a problem that a dead space is likely to be generated inside the artificial bone.

  Further, in the design system disclosed in Patent Document 2, when the three-dimensional shape data of the defect is generated based on the bone outline information for each tomographic position, and the defect exists on one side of the skull By generating the defect part by mirror image copy, the three-dimensional shape data of the defect part is generated. For this reason, since the design system of Patent Document 2 only generates the three-dimensional shape data of the defect part by restoring the defect part by mirror image copy, the void as the region caused by skin atrophy or brain resection is accurately determined. There is a problem that it is difficult to form an artificial bone that can be buried, and a dead space is likely to be generated inside the artificial bone.

  In view of the above circumstances, the present invention can form an artificial bone that can accurately fill a void as a region caused by skin atrophy or brain resection, and can prevent the occurrence of a dead space. It is an object of the present invention to provide a design method for a replacement artificial bone, a design apparatus for a skull replacement artificial bone, and a program.

  The skull replacement artificial bone design method according to the first aspect of the present invention for achieving the above object relates to a skull replacement artificial bone design method for designing an artificial bone that fills a defect in the skull. And the method for designing a skull-complementary artificial bone according to the first invention includes an artificial bone contour data acquisition step for acquiring artificial bone contour data, which is data of the contour of an artificial bone corresponding to a defect of a skull of a patient, Skin shape data acquisition step for acquiring skin shape data, which is shape data of the skin surface in the skin portion, based on a pixel density portion corresponding to the skin portion in the cross-sectional image of the patient's head; and the skin shape data An artificial bone inner surface shape data forming step for forming artificial bone inner surface shape data which is shape data of the inner surface of the artificial bone along the shape of the skin surface on the surface of the defect portion, and the artificial bone Based on the outer shape data and the artificial bone inner surface shape data, the outer shape of the artificial bone from which the artificial bone outer shape data is acquired and the inner surface shape data of the artificial bone are shaped. Is the form the thickness data of the artificial bone to fill between the inner surface of the artificial bone was, characterized in that it and a artificial bone thickness data forming step.

  According to the present invention, the shape data of the skin surface is acquired based on the pixel density portion corresponding to the skin portion in the cross-sectional image of the head, and based on the acquired shape data of the artificial bone along the shape of the skin surface on the surface of the defect portion The shape data of the inner surface is formed. Based on the shape data, artificial bone thickness data for filling the space between the outer shape of the artificial bone and the inner surface of the artificial bone is formed. For this reason, it is possible to form an artificial bone having a shape capable of accurately filling a void as a region caused by skin atrophy or brain resection. As a result, the generation of dead space is prevented.

  According to a second aspect of the present invention, there is provided a skull replacement artificial bone design method according to the first aspect of the invention, wherein in the skin shape data acquisition step, the plurality of cross-sectional images in a parallel cross section of the patient's head. Obtaining curve data formed by continuously forming a plurality of intersections where a plurality of virtual lines extending radially from a central position, which is a predetermined point in the skull of the patient, and the skin surface in the skin portion are curved. Thus, the skin shape data is acquired.

  According to the present invention, skin shape data can be easily obtained by acquiring curve data obtained by continuing the intersection point where a virtual line extending radially from the center position in the skull and the skin surface intersect with each other for each cross-sectional image. Can be obtained.

  A skull replacement artificial bone design apparatus according to a third aspect of the present invention relates to a skull replacement artificial bone design apparatus for designing an artificial bone that fills a defect in a skull. And the skull replacement artificial bone design device according to the third invention comprises an artificial bone contour data acquisition unit for acquiring artificial bone contour data which is data of the contour of an artificial bone corresponding to a defect portion of a skull of a patient, A skin shape data acquisition unit that acquires skin shape data that is shape data of the skin surface in the skin portion based on a pixel density portion corresponding to the skin portion in a cross-sectional image of the patient's head, and the skin shape data An artificial bone inner surface shape data forming unit for forming artificial bone inner surface shape data which is shape data of the inner surface of the artificial bone along the shape of the skin surface on the surface of the defect portion, and the artificial bone Based on the outer shape data and the artificial bone inner surface shape data, the artificial bone outer shape from which the artificial bone outer shape data was acquired and the artificial bone formed with the artificial bone inner surface shape data To form a thickness data of the artificial bone to fill the space between the inner surface, characterized in that it comprises a synthetic bone thickness data forming unit. According to the third aspect of the invention, the same effect as that of the first aspect of the invention can be achieved.

  A program according to a fourth aspect of the present invention relates to a program for executing, by a computer, the design of an artificial bone that fills a defect in a skull. And the program which concerns on 4th invention acquires the artificial bone external shape data which is the data of the external shape of the artificial bone corresponding to the defect | deletion part of a patient's skull in the said computer, The artificial bone external shape data acquisition step, Based on the skin shape data acquisition step for acquiring skin shape data, which is shape data of the skin surface in the skin portion, based on the portion of the pixel density corresponding to the skin portion in the cross-sectional image of the head, and based on the skin shape data Forming an artificial bone inner surface shape data which is shape data of the inner surface of the artificial bone along the shape of the skin surface on the surface of the defect portion, and the artificial bone outer shape data forming step; And the artificial bone inner surface shape data, the artificial bone outer shape data from which the artificial bone outer shape data was acquired and the artificial bone inner surface shape data. Wherein forming the thickness data of the artificial bone to fill the space between the formed the inner surface of the artificial bone, characterized in that to perform the artificial bone thickness data forming step. According to the fourth aspect of the invention, the same effect as that of the first aspect of the invention can be achieved.

  According to the present invention, an artificial bone capable of accurately filling a void as a region caused by skin atrophy or brain resection can be formed, and a dead bone cavity can be prevented from being generated. It is possible to provide a skull replacement artificial bone design apparatus and program.

1 is a block diagram showing a skull replacement artificial bone designing apparatus according to an embodiment of the present invention. It is a schematic diagram which shows the patient's head in the state which the defect | deletion part generate | occur | produced in the skull. It is a schematic diagram which shows the skull in the patient's head shown in FIG. It is a flowchart which shows the operation | movement flow of the design apparatus shown in FIG. 1, and the design method of the skull replacement artificial bone in this embodiment. It is a figure for demonstrating the data obtained by the operation | movement of the design apparatus shown in FIG. 1, and the CT image data acquisition step in the design method of this embodiment. It is a figure for demonstrating the artificial bone external shape data obtained by the operation | movement of the design apparatus shown in FIG. 1, and the artificial bone external shape data acquisition step in the design method of this embodiment. It is a figure for demonstrating the skin shape data obtained by the operation | movement of the design apparatus shown in FIG. 1, and the skin shape data acquisition step in the design method of this embodiment. It is a figure for demonstrating the process in which the skin shape data acquisition part in the skin shape data acquisition part of the design apparatus shown in FIG. 1 is acquired. It is a figure for demonstrating the process in which the skin shape data acquisition part in the skin shape data acquisition part of the design apparatus shown in FIG. 1 is acquired. It is a figure for demonstrating the artificial bone inner surface shape data obtained by the operation | movement of the design apparatus shown in FIG. 1, and the artificial bone inner surface shape data formation step in the design method of this embodiment. It is a figure for demonstrating the thickness data obtained by the operation | movement of the design apparatus shown in FIG. 1, and the artificial bone thickness data formation step in the design method of this embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The present invention provides a design method for a skull-complementing artificial bone and a design device for a skull-complementing artificial bone for designing an artificial bone that compensates for a defect in the skull, and also a design of an artificial bone that compensates for the defect in the skull. The present invention can be widely applied as a program to be executed by a computer.

  In addition, the design method of this embodiment (the method of designing a skull-complementing artificial bone) is performed by the operation of the design device of this embodiment (a device for designing a skull-complementing artificial bone). Moreover, the program of this embodiment is comprised as a program for performing the design of the artificial bone which compensates the defect | deletion part in a skull by the design apparatus of this embodiment which is a computer. And in this embodiment, the design method of this embodiment is implemented by the program of this embodiment being performed by the design apparatus of this embodiment.

  FIG. 1 is a block diagram schematically showing a configuration of a skull-repair artificial bone designing device 1 (hereinafter also simply referred to as “designing device 1”) according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing a patient's head 100 in a state where a part of the skull is lost or excised for the treatment of an accident or a disease and a defect is generated in the skull. 3 is a schematic diagram showing the skull 101 in the patient's head 100 shown in FIG.

  The design apparatus 1 shown in FIG. 1 is used as an apparatus for designing an artificial bone that compensates for the defect 101a with respect to the skull 101 in which the defect 101a has occurred as shown in FIG. In addition, as shown in FIG. 2, the surface of the defect | deletion part 101a which is a part which the bone | frame part in the skull 101 lost is in the state covered with the skin.

  The design apparatus 1 is provided with a CPU (Central Processing Unit), a storage device such as a memory, an input / output interface, and the like (not shown). Thereby, in the design apparatus 1, as shown in FIG. 1, CT image data acquisition part 21, artificial bone external shape data acquisition part 22, skin shape data acquisition part 23, artificial bone inner surface shape data formation part 24, artificial bone thickness A data forming unit 25, a storage unit 26, and the like are provided. The CT image data acquisition unit 21, the artificial bone outer shape data acquisition unit 22, the skin shape data acquisition unit 23, the artificial bone inner surface shape data formation unit 24, and the artificial bone thickness data formation unit 25 are stored in a storage device such as a CPU and a memory. And a predetermined program stored therein. The CPU of the design apparatus 1 functions as a CT image data acquisition unit 21, an artificial bone outer shape data acquisition unit 22, a skin shape data acquisition unit 23, an artificial bone inner surface shape data formation unit 24, and an artificial bone thickness data formation unit 25. Will be processed. In addition, a storage device such as a memory in the design apparatus 1 functions as the storage unit 26.

  The design device 1 starts processing based on an input operation from the input device 12 by a user (not shown), and the artificial bone is designed by executing the processing of the design device 1. The design device 1 is connected to the input device 12 and the display device 13.

  The input device 12 is a device for inputting an operation on the design device 1 by a user. The input device 12 is provided as an input device such as a keyboard or a pointing device such as a mouse. A user can input predetermined data necessary for designing an artificial bone to the design device 1 using the input device 12 and can operate the design device 1. The display device 13 is provided as a display device having a display screen, for example, and displays a processing result based on the control of the design device 1.

  Hereinafter, the CT image data acquisition unit 21, the artificial bone outer shape data acquisition unit 22, the skin shape data acquisition unit 23, the artificial bone inner surface shape data formation unit 24, the artificial bone thickness data formation unit 25, and the storage unit 26 in the design apparatus 1 The processing will be described together with the design method of the present embodiment that is implemented by operating the design apparatus 1.

  FIG. 4 is a flowchart showing the operation flow of the design apparatus 1 and the design method of the present embodiment. The design method of this embodiment includes CT image data acquisition step S101, artificial bone outer shape data acquisition step S102, skin shape data acquisition step S103, artificial bone inner surface shape data formation step S104, artificial bone thickness data formation step S105, and the like. Configured.

  In the present embodiment, the CPU of the design apparatus 1 reads and executes the program of the present embodiment stored in the memory of the design apparatus 1. Thereby, the program of this embodiment makes the design apparatus 1 which is a computer perform each said step (S101-S105), and the design method of this embodiment is implemented.

  The CT image data acquisition unit 21 is configured to acquire the CT image data 11. And the CT image data acquisition step S101 is performed by the process as the CT image data acquisition unit 21 being performed in the design apparatus 1.

  The CT image data 11 is obtained by tomography of the patient's head 100 using an X-ray CT (Computed Tomography) apparatus, and is a plurality of cross-sections perpendicular to the vertical direction of the patient's head 100 and parallel to each other. It is comprised as data of a cross-sectional image. The CT image data 11 is, for example, a semiconductor storage device such as CF (Compact Flash) and SD (Secure Digital), a magnetic recording medium such as a flexible disk, or a CD-ROM (Compact Disk Read Only Memory). ) And the like recorded in an optical recording medium and the like, and acquired by the CT image data acquisition unit 21. Alternatively, the CT image data 11 is read as image data from the above-described film or the like of each cross-sectional image via an image scanner (not shown) and acquired by the CT image data acquisition unit 21.

  FIG. 5 is a diagram for explaining one cross-sectional data in the CT image data 11 acquired by the CT image data acquisition unit 21, and schematically showing a corresponding cross-sectional image as the cross-sectional data. is there. The cross section shown in the schematic diagram of FIG. 5 is a cross section at a position corresponding to the defect 101a of the skull 101. As shown in FIG. 5, the cross-sectional image includes a skull 101 with an opening of the defect 101 a, a brain 102 disposed inside the skull 101, and a skin portion 103 covering the periphery of the skull 101 including the defect 101 a. The cross section appears.

  FIG. 6 is a diagram for explaining the artificial bone outline data 31 acquired as the surface shape data by the artificial bone outline data acquisition unit 22, and includes cross-sectional data corresponding to FIG. 5 including the artificial bone outline data 31. FIG. 3 is a diagram schematically showing a corresponding cross-sectional image. The artificial bone contour data acquisition unit 22 is configured to acquire artificial bone contour data 31 that is contour data of an artificial bone corresponding to the defect 101a of the skull 101 of the patient. And the artificial bone external shape data acquisition step S102 will be performed by the process as the artificial bone external shape data acquisition part 22 being performed in the design apparatus 1. FIG.

  The artificial bone contour data acquisition unit 22 assumes, for example, a virtual center plane C that bisects the head 100 at the center position in the left-right direction (the position of the center plane P is indicated by a dashed line C in FIG. 6). The artificial bone outline data 31 may be acquired based on the outline of the bone of the non-defect portion 101b having no defect 101a among the skulls 101 separated by the central plane P. In this case, a virtual bone outline is assumed in which the outline of the non-defect portion 101b is inverted to a plane-symmetrical position on the center plane C, and based on the portion arranged to close the defect portion 101a in the bone outline. The artificial bone outline data 31 may be acquired. Further, even if the portion arranged so as to close the defect portion 101a in the bone outline is corrected by changing the aspect ratio in the cross section of FIG. 6 or the like, the artificial bone contour data 31 is acquired. Good.

  FIG. 7 is a diagram for explaining the skin shape data 32 acquired by the skin shape data acquisition unit 23, and schematically shows a corresponding cross-sectional image as the cross-sectional data corresponding to FIG. 6 including the skin shape data 32. FIG. The skin shape data acquisition unit 23 acquires skin shape data 32 that is shape data of the skin surface in the skin portion 103 based on the pixel density portion corresponding to the skin portion 103 in the cross-sectional image of the patient's head 100. It is configured. And the skin shape data acquisition step S103 will be performed by the process as the skin shape data acquisition part 23 being performed in the design apparatus 1. FIG.

  FIGS. 8 and 9 are diagrams for explaining the process of acquiring the skin shape data 32 in the skin shape data acquiring unit 23 that executes the skin shape data acquiring step S103. In the skin shape data acquisition step S103, for each of a plurality of cross-sectional images in the parallel cross-section P of the patient's head 100, a plurality of virtual lines extending radially from the center position M, which is a predetermined point in the patient's skull 101. Curve data formed by continuing the intersection point Q where the radiation R and the skin surface in the skin portion 103 intersect with each other in a curve is acquired. And in each curve data corresponding to each cross section P, skin shape data 32 is acquired as surface shape data by combining adjacent intersections Q in curve data adjacent in the direction along the vertical direction of the head 100. Will be.

  In FIG. 8, with respect to the skin shape data 32 obtained as the surface shape data, only a portion corresponding to a part of the head 100 is schematically shown by a two-dot chain line. Further, in FIG. 8, as for the radiation R, only a part of the radiation R extending in a direction perpendicular to the vertical direction of the head 100 is schematically illustrated, and illustration of other radiation R is omitted. Yes. 9 shows the relationship between the radiation R and the intersection point Q in the cross section shown in FIG. 7. Since the radiation R crosses the cross section shown in FIG. 9 is shown as a projection view with respect to the cross section in FIG. In FIG. 9, the radiation R and the intersection point Q that intersect with the skin portion 103 on the non-defect portion 101b side are not shown. 8 and 9, the cross section P, the radiation R, and the intersection point Q are illustrated with a number smaller than the number of the actually set cross sections P, radiation R, and the intersection point Q in order to easily understand. ing.

  Note that the process in which the artificial bone outline data acquisition unit 22 acquires the artificial bone outline data 31 may be performed in the same manner as the process described with reference to FIGS. In this case, the shape data of the outer shape of the bone of the defect-free portion 101b is acquired by the same processing as the processing described with reference to FIGS. Then, based on the shape data of the outer shape of the bone of the non-defect portion 101b, the portion that is reversed to the plane symmetry position on the central plane C and blocks the defect portion 101a is extracted, and the artificial bone outer shape data 31 is acquired.

  FIG. 10 is a diagram for explaining the artificial bone inner surface shape data 33 formed by the artificial bone inner surface shape data forming unit 24. As cross-sectional data corresponding to FIG. It is a figure which shows a corresponding cross-sectional image typically. Based on the skin shape data 32, the artificial bone inner surface shape data forming unit 24 forms artificial bone inner surface shape data 33, which is the shape data of the inner surface of the artificial bone along the shape of the skin surface on the surface of the defect 101a. Is configured to do. And the artificial bone inner surface shape data formation step S104 is performed by performing the process as the artificial bone inner surface shape data forming unit 24 in the design apparatus 1.

  In the artificial bone inner surface shape data forming unit 24, for example, the shape data of the central portion of the artificial bone inner surface shape data 33 is determined by the shape data of the portion along the skin surface corresponding to the defect 101a in the skin shape data 32. It is formed. The shape data in the vicinity of the end portion of the artificial bone inner surface shape data 33 in each cross section P (see FIG. 8) is continuous with the edge portion of the defect 101a in the skull 101 and is also continuous with the artificial bone outer shape data 31. It is corrected so as to be formed.

  FIG. 11 is a diagram for explaining the thickness data 34 formed by the artificial bone thickness data forming unit 25. As a cross-sectional data corresponding to FIG. FIG. Based on the artificial bone outer shape data 31 and the artificial bone inner surface shape data 33, the artificial bone thickness data forming unit 25 acquires the artificial bone outer shape and the artificial bone inner surface shape data 33 from which the artificial bone outer shape data 31 has been acquired. The artificial bone thickness data 34 is formed so as to fill the space between the inner surface of the artificial bone. And the artificial bone thickness data formation step S105 will be performed by the process as the artificial bone thickness data formation part 25 being performed in the design apparatus 1. FIG. In the cross section shown in FIG. 11, the cross section of the thickness data 34 is illustrated as a hatched area.

  The storage unit 26 is acquired or formed by the CT image data acquisition unit 21, the artificial bone outer shape data acquisition unit 22, the skin shape data acquisition unit 23, the artificial bone inner surface shape data formation unit 24, and the artificial bone thickness data formation unit 25, respectively. Configured to store the data. The design device 1 is configured such that the data stored in the storage unit 26 is displayed on the display screen of the display device 13 based on the control of the design device 1 and can be confirmed by the user.

  Further, the artificial bone outer shape data 31, the artificial bone inner surface shape data 33, and the thickness data 34 stored in the storage unit 26 are output and recorded as design data 14 on an external recording medium or the like. Based on this design data 14, a molded body using a medical material such as ceramics or polyethylene (PE) is manufactured, and the molded body is further processed to compensate for the defect 101a in the skull 101 of the patient. An artificial bone is manufactured.

  The program of the present embodiment includes the above-described CT image data acquisition step S101, artificial bone outer shape data acquisition step S102, skin shape data acquisition step S103, artificial bone inner surface shape data formation step S104, and artificial bone thickness data formation step S105. May be configured to cause the design apparatus 1 to execute. Then, the program of the present embodiment is installed in a computer such as the design apparatus 1 and executed, whereby the design method of the present embodiment is performed.

  Further, the program of the present embodiment may be distributed in a state recorded on a recording medium, or may be distributed as data on the Internet. Specific examples of the recording medium include general-purpose semiconductor storage devices such as CF (Compact Flash) and SD (Secure Digital), magnetic recording media such as a flexible disk, or CD-ROM (Compact Disk Read). An optical recording medium such as “Only Memory”.

  As described above, according to the design device 1, the design method, and the program of the present embodiment, the shape data (skin shape) of the skin surface based on the pixel density portion corresponding to the skin portion 103 in the cross-sectional image of the head 100. Data 31) is acquired, and based on this, shape data (artificial bone inner surface shape data 33) of the inner surface of the artificial bone along the shape of the skin surface on the surface of the defect 101a is formed. Based on the shape data (31, 33), artificial bone thickness data 34 for filling the space between the outer shape of the artificial bone and the inner surface of the artificial bone is formed. For this reason, it is possible to form an artificial bone having a shape capable of accurately filling a void as a region caused by skin atrophy or brain resection. As a result, the generation of dead space is prevented.

  Further, according to the design device 1, the design method, and the program of the present embodiment, the intersection point Q where the virtual radiation R extending radially from the center position M in the skull 101 and the skin surface intersect with each other in a cross-sectional image is made continuous with a curve. By acquiring the curve data obtained in this way, the skin shape data 32 can be easily acquired.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, the following modifications may be made.

(1) In the above-described embodiment, an example in which CT image data is used as the cross-sectional image data of the head has been described as an example, but this need not be the case, and other than CT image data may be used as the cross-sectional image data of the head. The form in which data is used may be used. For example, image data obtained by MRI (Magnetic Resonance Imaging) may be used as the cross-sectional image data of the head.

(2) In addition, the shape data of the central portion of the artificial bone inner surface shape data may be formed based on the skin shape data, and corresponds to the missing portion of the skin shape data as in the above-described embodiment. The shape formed by the shape data of the portion along the surface of the skin is not necessary. In this case, for example, the shape data of the central portion of the artificial bone inner surface shape data is formed as a shape that spreads through a certain gap with respect to the shape data of the portion along the skin surface corresponding to the missing portion in the skin shape data. Such shape data may be used.

  INDUSTRIAL APPLICABILITY The present invention can be widely applied as a skull replacement artificial bone design method, a skull replacement artificial bone design device, and a program for designing an artificial bone that fills a defect in a skull.

DESCRIPTION OF SYMBOLS 1 Skull replacement artificial bone design apparatus 22 Artificial bone external shape data acquisition part 23 Skin shape data acquisition part 24 Skin inner surface shape data formation part 25 Artificial bone thickness data formation part 100 Head 101 Skull 101a Defect part 103 Skin part

Claims (4)

A design method for a skull-complementing artificial bone for designing an artificial bone that compensates for a defect in the skull,
Artificial bone contour data acquisition step for acquiring artificial bone contour data, which is data of the contour of the artificial bone corresponding to the defect portion of the skull of the patient;
A skin shape data acquisition step of acquiring skin shape data, which is shape data of the skin surface in the skin portion, based on a pixel density portion corresponding to the skin portion in the cross-sectional image of the patient's head;
An artificial bone inner surface shape data forming step for forming artificial bone inner surface shape data, which is shape data of an inner surface of the artificial bone along the shape of the skin surface on the surface of the defect based on the skin shape data; ,
Based on the artificial bone outer shape data and the artificial bone inner surface shape data, the outer shape of the artificial bone from which the artificial bone outer shape data was acquired, and the inner surface of the artificial bone on which the artificial bone inner surface shape data was formed, Forming a thickness data of the artificial bone that fills the gap, forming an artificial bone thickness data; and
A method for designing a skull-complementary artificial bone, comprising: A method for designing a skull-complementary artificial bone according to claim 1,
In the skin shape data acquisition step, for each of the plurality of cross-sectional images in a parallel cross section of the patient's head, a plurality of virtual lines extending radially from a central position, which is a predetermined point in the patient's skull, and the A method for designing a skull-complementary artificial bone, wherein the skin shape data is acquired by acquiring curve data formed by continuously forming intersection points where the skin surface of the skin portion intersects with a curve. A design device for a skull-complementing artificial bone for designing an artificial bone that compensates for a defect in the skull,
An artificial bone contour data acquisition unit for acquiring artificial bone contour data that is data of the contour of the artificial bone corresponding to the defect portion of the skull of the patient;
A skin shape data acquisition unit that acquires skin shape data, which is shape data of the skin surface of the skin portion, based on a pixel density portion corresponding to the skin portion in the cross-sectional image of the patient's head;
An artificial bone inner surface shape data forming unit that forms, based on the skin shape data, artificial bone inner surface shape data that is shape data of an inner surface of the artificial bone along the shape of the skin surface on the surface of the defect; ,
Based on the artificial bone outer shape data and the artificial bone inner surface shape data, the outer shape of the artificial bone from which the artificial bone outer shape data was acquired, and the inner surface of the artificial bone on which the artificial bone inner surface shape data was formed, Forming an artificial bone thickness data forming the artificial bone thickness data,
An apparatus for designing a skull-complementary artificial bone, comprising: A program for executing, by a computer, the design of an artificial bone that fills a defect in a skull,
In the computer,
Artificial bone contour data acquisition step for acquiring artificial bone contour data, which is data of the contour of the artificial bone corresponding to the defect portion of the skull of the patient;
A skin shape data acquisition step of acquiring skin shape data, which is shape data of the skin surface in the skin portion, based on a pixel density portion corresponding to the skin portion in the cross-sectional image of the patient's head;
An artificial bone inner surface shape data forming step for forming artificial bone inner surface shape data, which is shape data of an inner surface of the artificial bone along the shape of the skin surface on the surface of the defect based on the skin shape data; ,
Based on the artificial bone outer shape data and the artificial bone inner surface shape data, the outer shape of the artificial bone from which the artificial bone outer shape data was acquired, and the inner surface of the artificial bone on which the artificial bone inner surface shape data was formed, Forming a thickness data of the artificial bone that fills the gap, forming an artificial bone thickness data; and
A program characterized by having executed.

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