Method and apparatus for target position verification

• US 6,325,758 B1
• Filed: 10/27/1998
• Issued: 12/04/2001
• Est. Priority Date: 10/27/1997
• Status: Expired due to Term

• Current Assignee: Best Medical International Incorporated (TeamBest Group)
• Original Assignee: Nomos Corporation (North American Scientific, Inc.)
• Inventors: Huber, Richard E., Rosen, Brian S., Nash, Richard V., Campbell, Robert C., Carol, Mark P.
• Primary Examiner(s): Jaworski, Francis J.
• Application Number:
  US09/181,496
• Time in Patent Office: 1,134 Days
• Field of Search: 600/439, 600/407, 600/2-3, 600/7, 378/206, 378/65, 378/68-69, 364/413.21, 364/413.26, 601/2-4
• US Class Current: 600/439
• CPC Class Codes: A61B 8/4245 involving determining the position of the probe, e.g. with respect to an external reference frame or to the patient
• CPC Class Codes: A61B 8/4263 using sensors not mounted on the probe, e.g. mounted on an external reference frame
• CPC Class Codes: A61N 2005/1058 using ultrasound imaging
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: Y10S 128/916 Ultrasound 3-D imaging

Abstract

A method and apparatus for verifying the position of a target to be treated by a radiation therapy device may include an ultrasound probe used to generate ultrasound images of the target; a position sensing system for indicating the position of the ultrasound probe with respect to the radiation therapy device, whereby the location of the target with respect to the radiation therapy device is known; and the ultrasound image of the target may be aligned with radiation treatment data.

Claims

1. A method for verifying the position of a target within a body of a patient for use in a radiation treatment plan which includes at least two two-dimensional representations of treatment plan data corresponding to the target, comprising the steps of:

(a) disposing the patient on a treatment table of a radiation therapy device;

(b) providing an ultrasound probe mounted to a 3-D digitizer articulated arm;

(c) generating at least two two-dimensional ultrasound images of the target in the patient'"'"'s body, with the ultrasound probe being disposed in a known geometric orientation for each ultrasound image generated with the ultrasound probe disposed outside the body of the patient;

(d) displaying the ultrasound images of the target;

(e) displaying the representations of treatment plan data;

(f) aligning the displayed representations of treatment plan data with the displayed ultrasound images; and

(g) determining an amount and type of movement of the treatment table and/or radiation therapy device and/or patient required to dispose the target, with respect to the radiation therapy device, to conform to the desired position of the target in the radiation treatment plan.

2. The method of claim 1, wherein the displayed representations of treatment plan data includes at least one dose distribution contour.

3. The method of claim 1, wherein the displayed representations of treatment plan data includes at least one structure contour.

4. The method of claim 1, wherein the displayed representations of treatment plan data is geometric information concerning radiation beam projections and isocenter locations.

5. The method of claim 1, including the step of moving the treatment table with respect to the radiation therapy device to dispose the target to conform to the desired position of the target in the radiation treatment plan.

6. The method of claim 5, fuither including the step of repositioning the patient with respect to the treatment table to achieve rotational or translational alignment of the patient.

7. The method of claim 6, wherein at least one of the ultrasound images is a sagittal image, and the sagittal image is utilized to guide the repositioning of the patient to achieve rotational alignment of the patient.

8. The method of claim 5, including repeating steps (c) through (g).

9. The method of claim 8, including the step of storing the treatment plan data, representations of treatment plan data, and ultrasound images, for use in future procedures, including patient set-up, operator verification, physician review of patient records.

10. The method of claim 1, including the step of disposing the 3-D digitizer articulated arm upon a moveable support.

11. The method of claim 1, including the step of disposing the ultrasound image generating means in the known geometric orientation by aligning the 3-D digitizer articulated arm to the radiation therapy device.

12. The method of claim 11, wherein the radiation therapy device has a collimator, and the 3-D digitizer articulated arm is aligned to the radiation therapy device by releasably securing the 3-D digitizer articulated arm to the collimator.

13. The method of claim 11, wherein the radiation therapy device has a gantry and the 3-D digitizer articulated arm is aligned by identifying at least three points on the gantry by touching the 3-D digitizer articulated arm to the at least three points when the gantry is at a known position.

14. The method of claim 11, including the steps of disposing the 3-D digitizer articulated arm upon a moveable support, providing holes in the floor adjacent the treatment table, and aligning the 3-D digitizer articulated arm by registering the moveable support and the 3-D digitizer articulated arm to the holes.

15. The method of claim 1, wherein the at least two two-dimensional ultrasound images include an axial image and a sagittal image.

16. The method of claim 1, including the step of associating a tilt sensor with a position sensing system associated with the means for generating the ultrasound image.

17. A target position verification system for use by a user with a radiation therapy device for treating a target within a body of a patient and with a radiation treatment plan which includes at least two two-dimensional representations of treatment plan data with the location of the target in the representations of the treatment plan data being known, comprising:

(a) an ultrasound probe for generating at least two two-dimensional ultrasound images of the target;

(b) a position sensing system for indicating the position of the ultrasound probe with respect to the radiation therapy device, the position sensing system including a 3-D digitizer articulated arm having a first and a second end and the ultrasound probe is mounted to the first end of the 3-D digitizer articulated arm, whereby the location of the target with respect to the radiation therapy device is known; and

(c) a computer having a monitor associated therewith, adapted to;

(i) display on the monitor the ultrasound images of the target;

(ii) display on the monitor the representations of treatment plan data;

(iii) in response to user input, align the representations of treatment plan data with the ultrasound images; and

(iv) in response to the alignment, determine the difference between the location of the target in the ultrasound images and the location of the target in the representations of treatment plan data.

18. The system of claim 17, wherein the second end of the 3-D digitizer arm is associated with a moveable support.

19. The system of claim 17, including a tilt sensor associated with the position sensing system.

20. A method for verifying the position of a target within a body of a patient for use in a radiation treatment plan which includes at least two two-dimensional representations of treatment plan data corresponding to the target, comprising the steps of:

(a) disposing the patient on a treatment table of a radiation therapy device;

(b) providing an ultrasound image generator mounted to a 3-D digitizer articulated arm;

(c) generating at least two two-dimensional ultrasound images of the target in the patient'"'"'s body, with the ultrasound image generator being disposed in a known geometric orientation for each ultrasound image generated with the ultrasound generator disposed outside the body of the patient;

(d) displaying the ultrasound images of the target;

(e) displaying the representations of treatment plan data;

(f) aligning the displayed representations of treatment plan data with the displayed ultrasound images; and

(g) determining an amount and type of movement of the treatment table and/or radiation therapy device and/or patient required to dispose the target, with respect to the radiation therapy device, to conform to the desired position of the target in the radiation treatment plan.

21. The method of claim 20, wherein the displayed representations of treatment plan data includes at least one dose distribution contour.

22. The method of claim 20, wherein the displayed representations of treatment plan data includes at least one structure contour.

23. The method of claim 20, wherein the displayed representations of treatment plan data is geometric information concerning radiation beam projections and isocenter locations.

24. The method of claim 20, including the step of moving the treatment table with respect to the radiation therapy device to dispose the target to conform to the desired position of the target in the radiation treatment plan.

25. The method of claim 24, further including the step of repositioning the patient with respect to the treatment table to achieve rotational or translational alignment of the patient.

26. The method of claim 25, wherein at least one of the ultrasound images is a sagittal image, and the sagittal image is utilized to guide the repositioning of the patient to achieve rotational alignment of the patient.

27. The method of claim 24, including repeating steps (c) through (g).

28. The method of claim 27, including the step of storing the treatment plan data, representations of treatment plan data, and ultrasound images, for use in future procedures, including patient set-up, operator verification, physician review of patient records.

29. The method of claim 20, including the step of utilizing an ultrasound image probe as the ultrasound image generator.

30. The method of claim 29, including the step of disposing the 3-D digitizer articulated arm upon a moveable support.

31. The method of claim 29, including the step of disposing the ultrasound image generator in the known geometric orientation by aligning the 3-D digitizer articulated arm to the radiation therapy device.

32. The method of claim 31, wherein the radiation therapy device has a collimator, and the 3-D digitizer articulated arm is aligned to the radiation therapy device by releasably securing the 3-D digitizer articulated arm to the collimator.

33. The method of claim 31, wherein the radiation therapy device has a gantry and the 3-D digitizer articulated arm is aligned by identifying at least three points on the gantry by touching the 3-D digitizer articulated arm to the at least three points when the gantry is at a known position.

34. The method of claim 31, including the steps of disposing the 3-D digitizer articulated arm upon a moveable support, providing holes in the floor adjacent the treatment table, and aligning the 3-D digitizer articulated arm by registering the moveable support and the 3-D digitizer articulated arm to the holes.

35. The method of claim 20, wherein the at least two two-dimensional ultrasound images include an axial image and a sagittal image.

36. The method of claim 20, including the step of associating a tilt sensor with a position sensing system associated with the ultrasound image generator.

37. A target position verification system for use by a user with a radiation therapy device for treating a target within a body of a patient and with a radiation treatment plan which includes at least one two-dimensional representation of treatment plan data with the location of the target in the at least one representation of the treatment plan data being known, comprising:

(a) an ultrasound probe for generating at least one two-dimensional ultrasound images of the target;

(b) a position sensing system for indicating the position of the ultrasound probe with respect to the radiation therapy device, the position sensing system including a 3-D digitizer articulated arm having a first and a second end and the ultrasound probe is mounted to the first end of the 3-D digitizer articulated arm whereby the location of the target with respect to the radiation therapy device is known; and

(c) a computer having a monitor associated therewith, adapted to;

(i) display on the monitor the at least one ultrasound image of the target;

(ii) display on the monitor the at least one representation of treatment plan data;

(iii) in response to user input, align the representation of treatment plan data with the ultrasound image; and

(iv) in response to the alignment, determine the difference between the location of the target in the ultrasound images and the location of the target in the representations of treatment plan data.

38. The system of claim 37, wherein the second end of the 3-D digitizer arm is associated with a moveable support.

39. The system of claim 37, including a tilt sensor associated with the position sensing system.