Intensity-modulated ion therapy

• US 9,555,265 B2
• Filed: 11/18/2015
• Issued: 01/31/2017
• Est. Priority Date: 12/06/2011
• Status: Active Grant

• Current Assignee: LOMA Linda University Medical Center (Mission Healthcare Services LLC)
• Original Assignee: LOMA Linda University Medical Center (Mission Healthcare Services LLC)
• Inventors: Schulte, Reinhard W.
• Primary Examiner(s): Park, Edward
• Application Number:
  US14/945,214
• Publication Number:
  US 20160144201A1
• Time in Patent Office: 440 Days
• US Class Current: 1/1
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1031 using a specific method of dose optimization
• CPC Class Codes: A61N 5/1039 using functional images, e.g. PET or MRI
• CPC Class Codes: A61N 5/1077 Beam delivery systems
• CPC Class Codes: A61N 5/1084 for delivering multiple intersecting beams at the same time, e.g. gamma knives

Abstract

The therapeutic treatment of a patient using intensity-modulated proton therapy is described. In one example, a method of creating a proton treatment plan is presented that divides volumes of interest into sub-volumes, applies dose constraints to the sub-volumes, finds one or more feasible configurations of a proton therapy system, and selects a proton beam configuration that improves or optimizes one or more aspects of proton therapy. In some implementations, the method of dividing volumes into sub-volumes includes creating fractional sub-volumes based at least in part on proximity to a target volume boundary. In some implementations, the method of finding an improved or optimal proton beam configuration from a set of feasible configurations includes finding a minimum of a cost function that utilizes weighting factors associated with treatment sites.

Claims

1. A method for performing intensity-modulated ion therapy, the method comprising:

obtaining positional information of structures within or on the patient;

identifying a feature of interest to be targeted by the ion therapy, the feature of interest comprising at least a portion of a structure within or on the patient;

identifying a volume of interest that includes the feature of interest, the volume of interest being larger than the feature of interest;

dividing the volume of interest into a plurality of sub-volumes such that the feature of interest comprises one or more sub-volumes;

setting a dose constraint for individual sub-volumes;

generating one or more ion treatment plans that satisfy each of the dose constraints of the individual sub-volumes; and

delivering ions to the patient using a selected ion treatment plan from the one or more generated ion treatment plans,

wherein individual sub-volumes comprise a group of voxels that are within a range of defined distances from the feature of interest, the range of defined distances from the feature of interest being different for different sub-volumes.

2. The method of claim 1, wherein delivering ions to the patient comprises delivering protons.

3. The method of claim 1, wherein delivering ions to the patient comprises delivering carbon ions.

4. The method of claim 1, wherein dividing the volume of interest into a plurality of sub-volumes comprises dividing the volume of interest into a grid of dose calculation points.

5. The method of claim 1, wherein setting a dose constraint for individual sub-volumes comprises receiving an input from a user.

6. The method of claim 1, wherein generating one or more ion treatment plans that satisfy each of the dose constraints of the individual sub-volumes comprises using an inverse problem solver to determine ion beam characteristics predicted to deliver radiation doses to the plurality of sub-volumes within the dose constraint.

7. The method of claim 1, wherein the dose constraint comprises a minimum dose constraint.

8. The method of claim 1, wherein the dose constraint is set based at least in part on the range of defined distances from the feature of interest.

9. An intensity-modulated ion therapy system comprising:

an ion delivery system configured to deliver one or more beams of ions to a patient;

an ion detector configured to measure a number of ions delivered; and

one or more physical processors configured to perform the steps of;

obtaining positional information of structures within or on the patient;

identifying a feature of interest to be targeted by the ion therapy, the feature of interest comprising at least a portion of a structure within or on the patient;

identifying a volume of interest that includes the feature of interest, the volume of interest being larger than the feature of interest;

dividing the volume of interest into a plurality of sub-volumes such that the feature of interest comprises one or more sub-volumes;

setting a dose constraint for individual sub-volumes;

generating one or more ion treatment plans that satisfy each of the dose constraints of the individual sub-volumes; and

delivering one or more beams of ions to the patient using a selected ion treatment plan from the one or more generated ion treatment plans;

wherein individual sub-volumes comprise a group of voxels that are within a range of defined distances from the feature of interest, the range of defined distances from the feature of interest being different for different sub-volumes.

10. The therapy system of claim 9, wherein the one or more beams of ions comprises a beam of protons.

11. The therapy system of claim 9, wherein the one or more beams of ions comprises a beam of carbon ions.

12. The therapy system of claim 9, wherein the one or more physical processors is further configured to generate one or more ion treatment plans that satisfy each of the dose constraints of the individual sub-volumes comprises using an inverse problem solver to determine ion beam characteristics predicted to deliver radiation doses to the plurality of sub-volumes within the dose constraint.

13. The therapy system of claim 9, wherein the dose constraint comprises a maximum dose constraint.