Tumor Tracking System and Method for Radiotherapy

• US 20120226152A1
• Filed: 03/03/2011
• Published: 09/06/2012
• Est. Priority Date: 03/03/2011
• Status: Abandoned Application

• Current Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Electric Research Laboratories, Inc. (Mitsubishi Electric Corporation)
• Inventors: Porikli, Fatih M.
• Application Number:
  US13/039,906
• Publication Number:
  US 20120226152A1
• Time in Patent Office: Days
• US Class Current: 600/427
• CPC Class Codes: A61B 5/0036 including treatment, e.g., using an implantable medical device, ablating, ventilating
• CPC Class Codes: A61B 5/1114 Tracking parts of the body
• CPC Class Codes: A61B 5/1128 using image analysis A61B5/1127 takes precedence
• CPC Class Codes: A61B 5/113 occurring during breathing
• CPC Class Codes: A61B 5/1135 by monitoring thoracic expansion
• CPC Class Codes: A61B 6/12 Arrangements for detecting or locating foreign bodies
• CPC Class Codes: A61B 6/4458 the source unit or the detector unit being attached to robotic arms
• CPC Class Codes: A61B 6/5288 involving retrospective matching to a physiological signal
• CPC Class Codes: A61N 2005/1058 using ultrasound imaging
• CPC Class Codes: A61N 2005/1059 using cameras imaging the patient
• CPC Class Codes: A61N 2005/1061 using an x-ray imaging system having a separate imaging source
• CPC Class Codes: A61N 2005/1062 using virtual X-ray images, e.g. digitally reconstructed radiographs [DRR]
• CPC Class Codes: A61N 2005/1074 Details of the control system, e.g. user interfaces
• CPC Class Codes: A61N 2005/1087 Ions; Protons
• CPC Class Codes: A61N 5/1037 taking into account the movement of the target, e.g. 4D-image based planning
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/1067 in real time, i.e. during treatment
• CPC Class Codes: A61N 5/1068 Gating the beam as a function of a physiological signal
• CPC Class Codes: A61N 5/1083 Robot arm beam systems

Abstract

A system and method for tracking a tumor includes a regression module for selecting, using a motion signal and a regression function, a feature signal from a set of feature signals, each feature signal in the set of feature signals represents a medical image of the body of the patient, wherein the motion signal represents a motion of a surface of a skin of the patient caused by the respiration, and wherein the regression function is trained based on a set of observations of the motion signal synchronized with the set of feature signals; and a registration module for determining the location of the target object using the feature signal and a registration function, wherein the registration function registers each feature signal to a breath-hold location of the target object identified.

Claims

1. A system for facilitating an operation of a treatment delivery system based on a location of a target object in a body of a patient, wherein the location is subject to a motion caused by respiration of the patient, comprising:

a regression module for selecting, using a motion signal and a regression function, a feature signal from a set of feature signals, each feature signal in the set of feature signals represents a medical image of the body of the patient, wherein the motion signal represents a motion of a surface of a skin of the patient caused by the respiration, and wherein the regression function is trained based on a set of observations of the motion signal synchronized with the set of feature signals;

a registration module for determining the location of the target object using the feature signal and a registration function, wherein the registration function registers each feature signal to a three-dimensional (3D) imaging data having a breath-hold location of the target object identified; and

a control module for generating a command to facilitate the operation of the treatment delivery system based on the location.

2. The system of claim 1, further comprising:

an update module for updating the regression function and the registration function based on a subset of feature signals representing a subset of medical images.

3. The system of claim 2, wherein a size of a subset of the feature signals is less than a size of the set of the feature signals,

4. The system of claim 3, wherein each feature signal in the subset of feature signals is extracted from a low-dosage medical image.

5. The system of claim 2, wherein each feature signal in the subset of feature signals is acquired when an observation of the motion signal matches an observation from a set of motion observations, wherein each motion observation from the set of motion observations corresponds to a feature signal from a set of key feature signals representing different locations of the target object.

6. The system of claim 1, further comprising:

an alignment module for updating the registration function with global coordinates of the breath-hold location of the target object.

7. The system of claim 2, wherein the regression function and the registration function are determined during a planning session, and wherein the regression function and the registration function are updated during the treatment session.

8. The system of claim 1, wherein the 3D imaging data acquired during a planning session using a breath hold procedure.

9. The system of claim 1, further comprising:

a processor for controlling the treatment delivery system, such that a beam of radiation is directed at the location of the target object.

10. The system of claim 1, further comprising:

a motion sensor for determining the motion signal.

20. The system of claim 1, further comprising:

means for determining the regression function and the registration function.

11. A method for controlling an operation of a treatment delivery system such that a beam of radiation is directed at a target object in a body of a patient for a duration of treatment session, wherein a location of the target object is subject to a motion, comprising the steps of:

selecting, using a motion signal and a regression function, a feature signal from a set of feature signals, each feature signal in the set of feature signals represents a medical image of the body of the patient, wherein the motion signal represents a motion of a surface of a skin of the patient caused by the respiration, and wherein the regression function is trained based on a set of observations of the motion signal synchronized with the set of feature signals;

determining the location of the target object using the feature signal and a registration function, wherein the registration function registers each feature signal to a digitally reconstructed radiograph (DRR) image having a breath-hold location of the target object identified; and

controlling the operation of the treatment delivery system based on the location, such that a beam of radiation is directed at the location of the target object.

12. The method of claim 11, further comprising:

updating the regression function during the treatment session.

13. The method of claim 11, further comprising:

updating the registration function during the treatment session.

14. The method of claim 11, further comprising:

updating the regression and the registration functions during the treatment session based on a subset of feature signals representing a subset of medical images representing different locations of the target object.

15. The system of claim 11, wherein the target object is a tumor, the medical image is an x-ray image, and the DRR image is determined from three-dimensional (3D) imaging data acquired using a breath hold procedure.

16. The method of claim 11, further comprising:

acquiring the set of medical images concurrently with the set of observations of the motion signal;

extracting the set of feature signals from corresponding medical images in the set of medical images; and

training the regression function based on corresponding pairs of the set of feature signals and the set of observations of the motion signal.

17. The method of claim 16, further comprising:

determining an aligned medical image that is best aligned with the DRR image;

tracking pixels in each medical images from pixels of the aligned image to determine a set of registration matrices; and

determining the registration function based on the set of registration matrices.

18. A system for facilitating an operation of a treatment delivery system based on a location of a tumor in a body of a patient, wherein the location is subject to a motion caused by respiration of the patient, comprising:

a regression module for selecting, using a motion signal and a regression function, a feature signal from a set of feature signals, each feature signal in the set of feature signals represents a medical image of the body of the patient, wherein the motion signal represents a motion of a skin of the patient caused by the respiration, and wherein the regression function is trained based on a set of observations of the motion signal synchronized with the set of feature signals;

a registration module for determining the location of the tumor using the feature signal and a registration function, wherein the registration function registers each feature signal to a breath-hold location of the tumor; and

an update module for updating the regression function and the registration function based on a subset of feature signals representing different locations of the tumor.

19. The system of claim 18, further comprising:

an alignment module for updating the registration function with global coordinates of the breath-hold location of the tumor;

a motion sensor for determining the motion signal; and

a processor for controlling the treatment delivery system, such that a beam of radiation is directed at the location of the target object.