System and method for producing a three-dimensional model

• US 7,702,380 B1
• Filed: 11/03/2000
• Issued: 04/20/2010
• Est. Priority Date: 11/03/1999
• Status: Expired due to Fees

• Current Assignee: Osteoplastics, LLC
• Original Assignee: Case Western Reserve University
• Inventors: Dean, Howard David
• Primary Examiner(s): Casler; Brian
• Assistant Examiner(s): RAMIREZ, JOHN FERNANDO
• Application Number:
  US10/129,308
• Time in Patent Office: 3,455 Days
• Field of Search: 600/426, 600/414, 600/410, 378/21, 382/128, 382/131, 382/171, 382/172, 382/173, 382/181
• US Class Current: 600/426
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects

Abstract

A shape of a medical device to be implanted into a subject is verified by acquiring a plurality of inter-fiduciary marker dimensions from the subject. Three-dimensional image data of the markers and a tissue of interest, included in the subject, is obtained. Respective measurements between the fiduciary markers around the subject and in the image data are confirmed. The tissue of interest and the fiduciary markers are identified in the image data. Points of the tissue of interest and the fiduciary markers are rendered as a 3-dimensional surface representation. A 3-dimensional model of the tissue of interest and the fiduciary markers is generated as a function of the surface representation. A shape of the medical device to be implanted into the subject is determined as a function of the 3-dimensional model.

Claims

1. A method of designing a customized implant that is configured to correct a defect in a tissue of interest in a patient, the method comprising:

positioning a plurality of fiducials in a fixed relationship to the patient;

obtaining image data representing a volume image of the fiducials and the tissue of interest;

validating respective measurements between the fiducials in the fixed relationship to the patient and in the image data;

correcting for image acquisition errors detected in the validating step;

segmenting the tissue of interest and the fiducials from the image data;

rendering points of the tissue of interest and the fiducials as a 3-dimensional surface representation;

creating a 3-dimensional model of the tissue of interest and the fiducials as a function of the 3-dimensional surface representation, thereby defining a 3-dimensional model of the defect in the tissue of interest; and

creating a 3-dimensional model of the implant based on the 3-dimensional model of the defect.

2. The method as set forth in claim 1, wherein the step of positioning the fiducials includes:

placing markers on the patient, the markers having a density where each creates an identifiable spot in the volume image.

3. The method as set forth in claim 1, wherein the step of positioning the fiducials includes:

placing a frame of or separate markers, which have sufficient density to create an identifiable constellation of spots in the volume image, on an external surface of the patient to surround the tissue of interest.

4. The method as set forth in claim 1, wherein the step of validating includes:

comparing distances between the fiducials, seen in the volume image of the fiducials and the tissue of interest, to distances collected prior to the image acquisition.

5. The method as set forth in claim 1, further including:

validating respective measurements between the fiducials and in the 3-dimensional surface representation of the tissue of interest and the fiducials.

6. The method as set forth in claim 5, further including:

validating respective measurements between the fiducials in the fixed relationship to the patient, taken before the patient is imaged, compared to the analogous dimensions seen in the volume image and the 3-dimensional model of the tissue of interest and the fiducials.

7. The method as set forth in claim 1, further including:

interpolating the image data for smoothing and resolving image resolution of the surface representation.

8. The method as set forth in claim 1, wherein the segmenting step includes:

bridging the fiducials to the tissue of interest.

9. A method for determining a shape of a medical device to be implanted into a subject, the method comprising:

positioning a plurality of markers around the subject;

obtaining 3-dimensional image data of the markers and a tissue of interest included in the subject;

confirming respective measurements between the markers around the subject and in the image data;

identifying the tissue of interest and the markers in the image data;

rendering points of the tissue of interest and the markers as a 3-dimensional surface representation;

generating a 3-dimensional model of the tissue of interest and the markers as a function of the surface representation; and

determining a shape of the medical device to be implanted into the subject as a function of the 3-dimensional model.

10. The method as set forth in claim 9, wherein the 3-dimensional image data is represented as voxels, the rendering step including:

producing a solid rendering of the voxel data.

11. The method for determining a shape of a medical device as set forth in claim 9, wherein the rendering step includes:

producing an iso-surface image of the tissue of interest and the fiducials.

12. The method as set forth in claim 9, wherein the rendering step includes:

rendering an external surface of the tissue of interest.

13. The method as set forth in claim 9, wherein the positioning step includes:

placing markers on the subject, the markers having a density for creating an identifiable spot in the 3-dimensional image data.

14. The method as set forth in claim 9, further including:

confirming respective measurements between the markers on the subject as the markers on the subject were before imaging and the markers in the 3-dimensional surface representation, and

confirming respective measurements between the markers on the subject as the markers on the subject were and the markers in the 3-dimensional model of the tissue of interest and the markers.

15. The method as set forth in claim 14, further including:

after any one of the confirming steps, correcting for positional errors detected in the respective confirming step.

16. A system for determining a shape of a medical device to correct a defect in a tissue of interest in a patient, the system comprising:

a plurality of fiducials positioned on the patient;

means for obtaining 3-dimensional image data of the fiducials and the tissue of interest included in the patient;

means for validating respective measurements between the fiducials around the patient and in the image data;

means for correcting at least some errors detected by the validating means;

means for identifying the tissue of interest and the fiducials in the image data;

means for rendering points of the tissue of interest and the fiducials as a 3-dimensional surface representation;

means for generating a 3-dimensional model of the tissue of interest and the fiducials as a function of the surface representation; and

means for determining the shape of the medical device as a function of the 3-dimensional model.

17. The system as set forth in claim 16, further including:

a frame on which the fiducials are attached, the frame being placed around the patient.

18. The system as set forth in claim 16, wherein the means for validating compares distances between the fiducials on the patient to the distances between the fiducials as the fiducials appear in the 3-dimensional surface representation.

19. The system as set forth in claim 16, wherein the means for rendering produces an iso-surface of the tissue of interest and the fiducials.