Methods and systems for image-guided placement of implants

• US 7,194,120 B2
• Filed: 05/29/2003
• Issued: 03/20/2007
• Est. Priority Date: 05/29/2003
• Status: Expired due to Fees

• Current Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Wicker, Ryan B., Tedla, Buzuayehu
• Primary Examiner(s): Bali; Vikkram
• Application Number:
  US10/448,263
• Publication Number:
  US 20040240715A1
• Time in Patent Office: 1,391 Days
• Field of Search: 382/128, 382/173, 382/300, 382/199, 378/42, 378/54, 600/407, 600/425, 600/426, 600/427
• US Class Current: 382/128
• CPC Class Codes: A61B 17/1735 for rasps or chisels
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 2017/564 Methods for bone or joint treatment
• CPC Class Codes: A61B 2090/364 Correlation of different images or relation of image positions in respect to the body
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: G06T 2207/30008 Bone
• CPC Class Codes: G06T 7/70 Determining position or orientation of objects or cameras camera calibration G06T7/80

Abstract

Methods and computer systems for determining the placement of an implant in a patient in need thereof comprising the step of analyzing intensity-based medical imaging data obtained from a patient, isolating an anatomic site of interest from the imaging data, determining anatomic spatial relationships with the use of an algorithm, wherein the algorithm is optionally automated.

Claims

1. A method for determining an optimal placement of a pedicle screw in a patient from imaging data obtained from a medical imaging device, comprising:

receiving medical imaging data that includes one or more images of a bony structure of a spine of the patient;

determining surface boundaries of the bony structure for one or more of the images; and

calculating an optimal trajectory of the pedicle screw having a predetermined initial diameter within the surface boundaries, wherein the optimal trajectory is automatically calculated to be within the surface boundaries by a computer processor performing an algorithm mathematically comparing the surface boundaries on a computer.

2. The method of claim 1, further comprising calculating an optimal diameter of the pedicle screw to replace the predetermined initial diameter, wherein the optimal diameter is automatically calculated to be within the surface boundaries by the computer processor performing the algorithm mathematically comparing the surface boundaries on the computer.

3. The method of claim 1, further comprising calculating an optimal depth to insert the pedicle screw, wherein the optimal depth is calculated by the computer processor performing a second algorithm on the computer.

4. The method of claim 1, wherein the medical imaging data comprise intensity-based imaging data.

5. The method of claim 1, wherein the medical imaging data are chosen from the group consisting of computed tomography data, positron emission tomography data, ultrasound data, and magnetic resonance imaging data.

6. The method of claim 1, further comprising analyzing the medical imaging data to determine if the algorithm is compatible with the imaging data.

7. The method of claim 1, wherein the determining surface boundaries comprises:

isolating the bony structure of the spine of the patient from the medical imaging data; and

determining the minimum thickness of a spinal pedicle, a pedicle length, and an orientation to the spine of the patient.

8. The method of claim 1, wherein calculating the optimum trajectory includes performing a least squares fit or weighted least squares fit on a locus of mid-points for minimum transverse pedicle widths of one or more of the images.

9. A computer system for determining an optimal placement of a pedicle screw in a patient from imaging data obtained from a medical imaging device, comprising:

one or more process; and

a computer readable medium connected to the processors, the computer readable medium including processor instructions configured to be read by the processors and thereby cause the processors to;

receive medical imaging data that includes one or more images of a bony structure of a spine of the patient;

determine surface boundaries of the bony structure for one or more of the images;

calculate an optimal trajectory, an optimal diameter and an optimal depth of the pedicle screw within the surface boundaries, wherein the optimal trajectory. the optimal diameter and the optimal depth are automatically calculated to be within the surface boundaries by mathematically comparing the surface boundaries; and

output of the optimal trajectory, the optimal diameter and the optimal depth.

10. The computer system of claim 9, wherein the processor instructions are further configured to be read by the processors and thereby cause the processors to:

interpolate the imaging data;

segment the interpolated imaging data;

extract a boundary of the bony structure from the interpolated imaging data;

identify a pedicle from the extracted boundary; and

calculate a minimum pedicle width, a maximum depth and a direction of the pedicle based on the coordinate system of the medical imaging data.

11. The computer system of claim 9, wherein calculating the optimum trajectory includes performing a least squares fit or weighted least squares fit on a locus of mid-points for minimum transverse pedicle widths of one or more of the images.

12. The computer system of claim 9, wherein the optimal trajectory, the optimal diameter and the optimal depth are output to a robotic device.

13. The computer system of claim 9, wherein the optimal trajectory, the optimal diameter and the optimal depth are output on a computer display.

14. The computer system of claim 9, wherein the optimal trajectory, the optimal diameter and the optimal depth are output to another computer system.

15. A computer system for determining an optimal placement of a pedicle screw in a patient from imaging data obtained from a medical imaging device, comprising:

one or more processors; and

a computer readable medium connected to the processors, the computer readable medium including processor instructions configured to be read by the processors and thereby cause the processors to;

receive medical imaging data that includes one or more images of a bony structure of a spine of the patient;

determine surface boundaries of the bony structure for one or more of the images;

calculate an optimal trajectory and an optimal diameter of the pedicle screw within the surface boundaries, wherein the optimal trajectory and the optimal diameter are automatically calculated to be within the surface boundaries by mathematically comparing the surface boundaries; and

output of the optimal trajectory and the optimal diameter.

16. The computer system of claim 15, wherein the optimal trajectory and the optimal diameter are output to a robotic device.

17. The computer system of claim 15, wherein the optimal trajectory and the optimal diameter are output on a computer display.

18. The computer system of claim 15, wherein the optimal trajectory and the optimal diameter are output to another computer system.

19. A method for determining an optimal placement of an implant in a patient comprising:

receiving medical imaging data that includes one or more intensity-based images of the patient;

analyzing the medical imaging data;

isolating an anatomic site of interest from the medical imaging data;

determining anatomic spatial relationships from the medical imaging data to identify the optimal placement of the implant, wherein the determining includes a determination of a minimum thickness of the anatomic site, a length of the anatomic site, and an orientation to the anatomic site relative to the orientation of the patient; and

calculating an optimal trajectory of the pedicle screw having a predetermined initial diameter within the anatomic site, wherein the optimal trajectory is automatically calculated by a computer processor performing an algorithm mathematically comparing the anatomic spatial relationships on a computer.

20. The method of claim 19, further comprising calculating an optimal diameter of the implant to replace the predetermined initial diameter, wherein the optimal diameter is automatically calculated to be within the surface boundaries by the computer processor performing the algorithm mathematically comparing the surface boundaries on the computer.

21. The method of claim 19, further comprising calculating an optimal depth to insert the implant, wherein the optimal depth is calculated by a computer processor performing a second algorithm on the computer.

22. The method of claim 19, wherein the medical imaging data are chosen from the group consisting of computed tomography data, positron emission tomography data, ultrasound data, and magnetic resonance imaging data.

23. The method of claim 19, further comprising analyzing the medical imaging data to determine if the algorithm is compatible with the medical imaging data.

24. A method for determining an optimal trajectory of an implant at an anatomic area of a patient, comprising:

receiving medical imaging data that includes one or more images of an anatomic site of the patient;

pre-processing the medical imaging data to ensure compatibility with an algorithm;

isolating an anatomic area of interest from the medical imaging data using a thresholding segmentation algorithm;

defining boundaries of the anatomic area in three-dimensions; and

calculating the optimal trajectory of the implant at the anatomic site using search calculations based on the anatomic site and the implant, wherein the optimal trajectory is automatically calculated by a computer processor performing the algorithm mathematically comparing the boundaries on a computer.

25. The method of claim 24, wherein the calculating includes calculations chosen from the group consisting of a minimum anatomic diameter, a maximum implant diameter, an optimum implant trajectory, a maximum length of the anatomic site, an optimum length of the implant, and combinations thereof.

26. The method of claim 25, wherein the calculations are search algorithms that include geometric considerations.

27. A computer program embodied in a computer readable medium for performing a determination of an optimal trajectory of an implant at an anatomic area of a patient from imaging data obtained from a medical imaging device, comprising:

a first computer code for receiving medical imaging data collected from one or more images of an anatomic site of the patient;

a second computer code for isolating an anatomic area of interest from one or more of the images using thresholding segmentation;

a third computer code for determining boundaries of the anatomic area of interest in three-dimensions;

a fourth computer code for calculating the optimal trajectory of the implant at the anatomic area based on the anatomic area and the implant, wherein the optimal trajectory is automatically calculated by mathematically comparing the boundaries; and

a fifth computer code for outputting the optimal trajectory.

28. The computer program of claim 27, wherein the fourth computer code includes calculations that comprise at least one of a minimum anatomic diameter, a maximum implant diameter, an optimum implant trajectory, a maximum length of the anatomic site, and an optimum length of the implant.

29. The computer program of claim 27, wherein medical imaging data are chosen from the group consisting of computed tomography data, positron emission tomography data, ultrasound data, and magnetic resonance imaging data.

30. The computer program of claim 29, further comprising a sixth computer code for initially pre-processing the medical imaging data.

31. The computer program of claim 30, wherein the sixth computer code comprises standardizing medical imaging data acquired from different medical imaging devices.

32. The computer program of claim 31, wherein standardizing medical image data comprises standardizing at least one of a pedicle length, a pedicle length, and a pedicle trajectory.

33. The computer program of claim 32, wherein the medical imaging data comprises two-dimensional data collected from a plurality two-dimensional image scans of the anatomic site.

34. The computer program of claim 33, wherein one or more of the plurality two-dimensional image scans have differing interslice distances, the sixth computer code for pre-processing the data further comprises a seventh computer code for interpolating one of the three-dimensions to equalize the interslice distances.

35. The computer program of claim 27, wherein the optimal trajectory is output to a robotic device.

36. The computer program of claim 27, wherein the optimal trajectory is output on a computer display.

37. The computer program of claim 27, wherein the optimal trajectory is output to another computer system.