CN-121987972-A - Method and apparatus for optimizing radiation treatment plan

Abstract

The present invention relates to a method and apparatus for optimizing a radiation treatment plan, a control circuit identifying a plurality of radiation treatment small arcs for a given radiation treatment platform and then identifying a corresponding isocenter position within a patient for each of the plurality of radiation treatment small arcs. The above may result in positioning the table isocenter at different locations within the patient during the radiation therapy session for different small arcs. The radiation treatment plan is optimized based on the plurality of small arcs and their corresponding isocenter positions. By one approach, these teachings include automatically dividing at least one initial template arc into at least two radiation therapy small arcs. By one approach, identifying a corresponding isocenter position for each of a plurality of radiation therapy sub-arcs can include identifying a corresponding isocenter position to maintain close proximity of a radiation therapy platform collimator to an outer surface of a patient.

Inventors

• E. Quisera

Assignees

• 西门子医疗国际股份有限公司

Dates

Publication Date

20260508

Application Date

20251105

Priority Date

20241107

Claims (20)

1. 1. A method for a radiation treatment platform having a corresponding platform isocenter and a movement capability to move a patient relative to the platform isocenter when radiation treatment is performed by the radiation treatment platform, the method comprising: By the control circuit: Identifying a plurality of radiation therapy small arcs for the radiation therapy platform; for each radiation therapy arc of the plurality of radiation therapy arcs, identifying a corresponding isocenter position within the patient to position the platform isocenter at a different position within the patient; A radiation treatment plan is optimized according to the plurality of radiation treatment arcs and corresponding isocenter positions of the radiation treatment arcs within the patient to provide an optimized radiation treatment plan.
2. 2. The method of claim 1, wherein identifying a corresponding isocenter position for each of the plurality of radiation therapy sub-arcs comprises identifying a corresponding isocenter position to maintain close proximity of a radiation therapy platform collimator to an outer surface of the patient.
3. 3. The method of claim 2, wherein the close proximity does not exceed a predetermined collimator-to-skin distance.
4. 4. The method of claim 3, wherein identifying the plurality of radiation therapy sub-arcs further comprises determining a sub-arc length of at least some of the radiation therapy sub-arcs as a function of the predetermined collimator-to-skin distance.
5. 5. The method of claim 4, wherein identifying the plurality of radiation therapy sub-arcs comprises automatically dividing at least one initial template arc into at least two radiation therapy sub-arcs.
6. 6. The method of claim 2, wherein the patient has a head, and wherein the outer surface of the patient comprises an outer surface of the head.
7. 7. The method of claim 6, wherein the optimized radiation treatment plan comprises a stereotactic radiosurgery radiation treatment plan.
8. 8. The method of claim 1, wherein identifying the plurality of radiation therapy sub-arcs for the radiation therapy platform comprises identifying radiation therapy sub-arcs in which at least two portions, but not all, overlap each other.
9. 9. The method of claim 1, further comprising: Therapeutic radiation is delivered to the patient through the radiation treatment platform during a treatment session using the optimized radiation treatment plan.
10. 10. The method of claim 9, further comprising: The distance between the patient's surface and the portion of the radiation treatment platform is automatically adjusted during the treatment session to avoid collisions between the patient's surface and the portion of the radiation treatment platform.
11. 11. An apparatus for a radiation treatment platform having a corresponding platform isocenter and a movement capability to move a patient relative to the platform isocenter when radiation treatment is performed by the radiation treatment platform, the apparatus comprising: A control circuit configured to: Identifying a plurality of radiation therapy small arcs for the radiation therapy platform; for each radiation therapy arc of the plurality of radiation therapy arcs, identifying a corresponding isocenter position within the patient to position the platform isocenter at a different position within the patient; the radiation treatment plan is optimized according to the plurality of radiation treatment arcs and corresponding isocenter positions of the radiation treatment arcs to provide an optimized radiation treatment plan.
12. 12. The apparatus of claim 11, wherein the control circuitry is configured to identify a corresponding isocenter position for each of the plurality of radiation therapy sub-arcs by identifying a corresponding isocenter position to maintain close proximity of a radiation therapy platform collimator to an outer surface of the patient.
13. 13. The apparatus of claim 12, wherein the close proximity does not exceed a predetermined collimator-to-skin distance.
14. 14. The apparatus of claim 13, wherein the control circuitry is further configured to identify the plurality of radiation therapy arcs by determining a arc length of at least some of the radiation therapy arcs according to a predetermined collimator-to-skin distance.
15. 15. The apparatus of claim 14, wherein the control circuitry is configured to identify the plurality of radiation therapy sub-arcs by automatically dividing at least one initial template arc into at least two radiation therapy sub-arcs.
16. 16. The apparatus of claim 12, wherein the patient has a head, and wherein the outer surface of the patient comprises an outer surface of the head.
17. 17. The apparatus of claim 16, wherein the optimized radiation treatment plan comprises a stereotactic radiosurgery radiation treatment plan.
18. 18. The apparatus of claim 11, wherein the control circuitry is configured to identify the plurality of radiation therapy sub-arcs for the radiation therapy platform by identifying at least two partial but not all mutually overlapping radiation therapy sub-arcs.
19. 19. The device of claim 11, wherein the control circuit is further configured to: Therapeutic radiation is delivered to the patient through the radiation treatment platform during a treatment session using the optimized radiation treatment plan.
20. 20. The device of claim 19, wherein the control circuit is further configured to: The distance between the patient's surface and the portion of the radiation treatment platform is automatically adjusted during the treatment session to avoid collisions between the patient's surface and the portion of the radiation treatment platform.

Description

Method and apparatus for optimizing radiation treatment plan Technical Field These teachings generally relate to treating a planned target volume of a patient with energy according to an energy-based treatment plan, and more particularly to optimizing an energy-based treatment plan. Background The use of energy to treat diseases is a known area of prior art effort. For example, radiation therapy is an important component of many treatment plans for reducing or eliminating harmful tumors. Unfortunately, the energy applied does not itself distinguish unwanted substances from adjacent tissues, organs or the like, which are desirable or even critical for the continued survival of the patient. Thus, energy, such as radiation, is typically applied in a discreet manner to at least attempt to confine the energy within a given target volume. So-called radiation treatment planning generally serves the above-mentioned function. Radiation treatment plans typically include specified values for each of a variety of treatment platform parameters during each of a plurality of consecutive fields. Treatment plans for radiation treatment sessions are typically automatically generated by a so-called optimization process. As used herein, "optimization" is understood to mean improving a candidate treatment plan, without necessarily ensuring that the results of the optimization are in fact the best solution. Such optimization typically involves automatically adjusting one or more physical therapy parameters (typically observing one or more corresponding limitations of these aspects simultaneously) and mathematically calculating the possible corresponding therapy results (e.g., dose levels) to identify a set of given therapy parameters that represent a good compromise between desired therapy results and avoiding adverse side effects. In at least some application settings, dose uniformity can be a useful measure of the quality of a given radiation treatment plan. The physical characteristics of the radiation treatment platform can have an impact on the outcome of dose uniformity. As an example, the penumbra of beamlets achieved by multi-leaf collimators may be a limiting factor affecting the achievable dose uniformity. The width of the penumbra of the beamlets depends on numerous design and implementation details of the multi-leaf collimator, such as the tip shape and the height of the multi-leaf collimator relative to the isocenter of the plateau. The latter can indirectly affect the width of the penumbra by increasing the distance that the beamlets travel in air before reaching the patient (and ultimately the target area). Applicant has determined that such airborne transmissions may cause scattering. Furthermore, since beamlets are typically divergent, the distance itself may also lead to an increase of penumbra. Drawings The foregoing needs are at least partially met by providing a method and apparatus for optimizing radiation therapy planning as described in the following detailed description, particularly when studied in conjunction with the drawings, wherein: FIG. 1 includes a block diagram configured in accordance with various embodiments of these teachings; FIG. 2 includes a flow chart configured in accordance with various embodiments of these teachings; FIG. 3 includes a schematic diagram configured in accordance with various embodiments of these teachings; FIG. 4 includes a schematic diagram configured in accordance with various embodiments of these teachings; FIG. 5 includes a schematic diagram configured in accordance with various embodiments of these teachings; FIG. 6 includes a schematic diagram configured in accordance with various embodiments of these teachings, and Fig. 7 includes a schematic diagram configured in accordance with various embodiments of the invention. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present teachings. Moreover, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are typically not depicted in order to facilitate a less obstructed view of these various embodiments of the present teachings. Certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. The terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by those skilled in the art as set forth above except where different specific meanings have otherwise been set forth herein. Unless explicitly stated otherwise, the term "or" as used herein should be construed as having a disjunctive structure rather than a