Method for modification of radiotherapy treatment delivery

• US 20050201516A1
• Filed: 03/06/2003
• Published: 09/15/2005
• Est. Priority Date: 03/06/2002
• Status: Active Grant

• Current Assignee: TomoTherapy Incorporated (Accuray Incorporated)
• Original Assignee: TomoTherapy Incorporated (Accuray Incorporated)
• Inventors: Ruchala, Kenneth J., Lu, Weiguo, Hughes, John H., Kapatoes, Jeffrey M., Reckwerdt, Paul J., Olivera, Gustavo H.
• Granted Patent: US 8,406,844 B2
• Time in Patent Office: Days
• US Class Current: 378/65
• CPC Class Codes: A61N 2005/1061 using an x-ray imaging system having a separate imaging source
• CPC Class Codes: A61N 5/103 Treatment planning systems
• CPC Class Codes: A61N 5/1038 taking into account previously administered plans applied to the same patient, i.e. adaptive radiotherapy
• CPC Class Codes: A61N 5/1065 Beam adjustment
• CPC Class Codes: A61N 5/1067 in real time, i.e. during treatment
• CPC Class Codes: A61N 5/1069 Target adjustment, e.g. moving the patient support

Abstract

The present invention provides a novel method of contoured-anatomy dose repositioning (CADR) as a means to automatically reposition a patient to better recover the planned dose distribution without reoptimize the treatment plan. Specifically, CADR utilizes planning CT images, the planned dose distribution, and on-line images for repositioning dose distribution on a given day. Contours are also placed upon the images using manual, automatic, template-based, or other techniques. CADR then optimizes the rigid-body repositioning of the patient so that the daily dose distribution closely matches the planned dose distribution. The present invention also provides a method of multiple-margin optimization with daily selection (MMODS) to improve radiation delivery without reoptimization. During the initial optimization procedure, plans are optimized for several margins of various contours (e.g., tight, medium, loose, etc.), or with different objectives (e.g., aggressive treatment, sensitive structure sparing, etc.). Similarly, if multiple patient image sets are available, plans can be optimized for the different anatomical layouts, either using current information, or accumulated information regarding the superposition of organ locations in the combination of images. A user can then choose in real time from a variety of optimized plans, generally with different margins, during the treatment process, and thereby compensate for a recognized change in size or position of the tumor or neighboring tissue.

Claims

1-13. -13. (canceled)

14. A method for modification of radiotherapy treatment delivery, the method comprising the steps of:

obtaining at least one treatment planning image from a patient to determine the relative location of target and sensitive structures;

preparing a treatment plan for the patient based on the at least one treatment planning image;

preparing a dose distribution plan for the patient based on the treatment plan;

obtaining at least one image from the patient at the time of treatment delivery to reposition the dose distribution for the patient, if necessary;

comparing the at least one treatment planning image to the at least one image taken of the patient at the time of treatment delivery to modify the treatment plan and dose distribution;

adjust patient position to better position patient'"'"'s internal anatomy relative to dose distribution;

optimize repositioning of the patient so that the dose distribution matches planned dose distribution;

optimize positioning of the fraction image, relative to the dose distribution, such that the dose received by relevant structures for the fraction is improved;

iterate as necessary to best combine a treatment plan and a patient position to achieve the desired dose distribution; and

deliver treatment to the patient.

15. The method of claim 14, wherein the dose distribution is calculated directly for a fraction image, or obtained indirectly based upon the planning image dose distribution, possibly in conjunction with image registration.

16. The method of claim 14, wherein the dose distribution is modified to take into account changes in patient position and/or changes in the patient'"'"'s anatomy.

17. The method of claim 14, wherein multiple objective functions can be used to achieve a precise treatment delivery.

18. The method of claim 14, wherein objective functions and weightings can be adjusted to fine-tune treatment delivery.

19. The method of claim 14, wherein objective function weights can be learned by the system based upon user training.

20. The method of claim 14, wherein results can be utilized either by moving the patient, modifying the delivery, or some combination of the two.

21. The method of claim 14, wherein contours can be generated by any available method, including but not limited to, manual contouring, automated contouring, deformable fusion, template-based automatic contouring, or a combination thereof.

22. The method of claim 14, wherein multiple margin optimization can be used to pre-optimize multiple plans with different margins (e.g., tight, medium, loose), or with different objectives (e.g., aggressive treatment, sensitive structure sparing), wherein an appropriate plan can be selected each day from the optimized possibilities, based upon best estimates of the patient'"'"'s anatomy that day.

23. The method of claim 14, wherein contoured anatomy dose repositioning and multiple margin optimization with daily selection can function independently, but can also be used together.

24. The method of claim 14, wherein contoured anatomy dose repositioning and multiple margin optimization with daily selection are not specific to a particular imaging modality or means of image acquisition, but can be applied to any form of obtaining more current patient positioning or anatomical information.

25. The method of claim 14, wherein contoured anatomy dose repositioning and multiple margin optimization with daily selection can be applied using any available planning images, which includes both initially available images and related treatment plans, but also to plans created with any images obtained subsequent to initial planning (such as during the course of treatment).

26. The method of claim 14, wherein process of plan selection in multiple margin optimization with daily selection, and the process of repositioning in contoured anatomy dose repositioning, can utilize information including but not limited to image information, contour information, dose-volume-histograms, and dosimetric information.