1. Navigation in Robotic Radiosurgery Achim Schweikard

2. beam Stereotactic Radiosurgery

4. Conventional Procedure

5. Stereotaxic Frame

6. Arc motion

7. Local Anesthesia

8. Concept

9. Image-Guidance

10. Robot System

12. Tumors in the chest or abdomen move due to respiration

13. Respiratory Motion

14. Respriatory Motion

15. Safety Margin Tumor

18. Beam

19. Robotic Arm

21. Volume of Sphere: 4/3  r 3

22. Hysteresis

23. Previous Work HD Kubo, BC Hill: Respiration gated radiotherapy treatment: a technical study. Phys. Med. Biol. 1996; 41: 83-91. T Tada et. al.:Lung cancer: Intermittent radiation synchronized with respiratory motion. Radiology, 1998; 207:779-783. MR Sonntag, ZW Lai: Characterization of respiratory motion for pediatric conformal 3D therapy. Med. Phys. 1996: 23: 1082.

24. Image-Guidance

25. Stereo X-Ray Camera System Camera ACamera B Gold fiducial

26. Infrared Tracking

27. Correlation

29. DART

30. System Overview

31. Correlation external chest vs. external abdomen

32. Motion Table Phantom Study (Overall Accuracy)

33. Robot Tracking

34. Prediction

35. Phantom Study

36. First Patient Treatment

37. Measured Target Excursion vs. Correlation Error

38. Follow-up Study

39. Four months follow-up

40. Treatment

42. Synchrony

43. Major Challenges Fiducial-less tracking

44. Implanting of Gold Fiducials

45. Respiration Courtesy Paul Sellars, JHU

46. Fiducial-Less Tracking: Principle Compute or acquire 4D CT

47. Principle Compute or acquire 4D CT Compute DRRs (2D Projections)

48. Principle Compute or acquire 4D CT Compute DRRs (2D Projections) Live Shots (2D x-ray pair)

49. Principle Compute or acquire 4D CT Compute DRRs (2D Projections) Live Shots (2D x-ray pair) Find the DRR that best matches live shots

50. Principle „Ground truth“

51. Principle i.e. Tumor position with time stamp

52. Principle Thus: same ground truth information as in fiducial-based tracking is available

53. Principle Correlation + Prediction real-time target position

54. Principle CT-Scan Inhalation CT-Scan Exhalation Intermediate CT-Scan 1 Intermediate CT-Scan n... „4D CT“ Best match determines respiratory state and therefore tumor position

55. Results Registration Implementation Uses Intensity-based rigid registration 2D/3D Optimization with the Hooke-Jeeves Pattern- Search Uses hardware-accelerated volume-rendering based on texture mapping as DRR generation technique Used metrics are correlation coefficient and mutual information

56. Results 7D Registration

58. Results single 2D/3D Registration

59. Computing time 10 seconds per registration

60. Conclusion Feasible w.r.t. computing time Feasibility w.r.t accuracy and reliability not yet established