Systems and methods for scintillation camera-based motion tracking in radiotherapy

Patent metadata

Field	Value
Publication number	US-2024207648-A1
Application number	US-202418597868-A
Country	US
Kind code	A1
Filing date	Mar 6, 2024
Priority date	Apr 24, 2020
Publication date	Jun 27, 2024
Grant date	—

Abstract

The disclosure provides a system for EGRT. The system may include a radiotherapy device for treating a subject. The radiotherapy device may include a scintillation camera that is directed at an ROI of the subject. The subject may be injected with a radioactive tracer or implanted with a radioactive marker before treatment. The ROI may undergo a physiological motion during the treatment. The system may deliver a treatment session to the subject by the radiotherapy device. During the treatment session, the system may acquire a target image of the ROI indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI by the scintillation camera, and adapt a radiation beam to be delivered to the subject with respect to the physiological motion of the ROI by adjusting the radiation beam based on the target image.

First claim

What is claimed is:

1 . A method for emission-guided radiation therapy (EGRT), comprising:
obtaining reference images of a region of interest (ROI) of a subject who receives a radiation treatment, wherein the subject is injected with a radioactive tracer or implanted with a radioactive marker before the radiation treatment, the ROI undergoes a physiological motion during the radiation treatment, and each of the reference images corresponds to one of a plurality of motion phases of the ROI; obtaining a target image of the ROI indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI during the radiation treatment; and adaptively adjusting, based on the reference images and the target image, the delivery of a radiation beam with respect to the physiological motion of the ROI during the radiation treatment.

2 . The method of claim 1 , wherein each of the reference images is indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI at a corresponding motion phase.

3 . The method of claim 2 , wherein the adaptively adjusting, based on the reference images and the target image, the delivery of a radiation beam with respect to the physiological motion of the ROI during the radiation treatment comprises:
determining, based on a comparison of the target image and each of the reference images, a target position of the ROI during the acquisition of the target image; and adjusting, based on the target position of the ROI, the delivery of the radiation beam.

4 . The method of claim 3 , wherein the determining a target position of the ROI comprises:
obtaining an image sequence relating to the ROI, the image sequence being reconstructed based on image data acquired in a scan of the subject, each image in the image sequence representing one motion phase of the plurality of motion phases and corresponding to a reference image of the same motion phase; selecting, among the reference images, a reference image that matches the target image; and determining, based on the image corresponding to the selected reference image in the image sequence, the target position of the ROI.

5 . The method of claim 4 , wherein the scan of the subject is at least one of a positron emission tomography (PET) scan, a single-photon emission computed tomography (SPECT), or a computed tomography (CT) scan.

6 . The method of claim 4 , wherein the reference images of the ROI are captured by a scintillation camera during the scan of the subject.

7 . The method of claim 1 , wherein the obtaining reference images of the ROI comprises:
obtaining an image sequence relating to the ROI, the image sequence being reconstructed based on image data acquired in a scan on the subject, each image in the image sequence representing one motion phase of the plurality of motion phases and corresponding to a reference image of the same motion phase; and generating, based on the image sequence, the reference images of the ROI according to a simulation algorithm.

8 . The method of claim 1 , wherein the radiation beam is a particle beam, and the method further comprises:
determining, based on the target image, a position of a Bragg peak of the particle beam; and evaluating, based on the position of the Bragg peak, the delivery of the treatment session.

9 . The method of claim 1 , wherein the target image is captured by at least one scintillation camera that is directed at the ROI during the radiation treatment and configured to detect single photons from annihilation photon pairs produced by interactions between the radioactive tracer or the radioactive marker and the subject.

10 . The method of claim 9 , further comprising:
determining, based on a trajectory of the radiation beam, a position of the at least one scintillation camera, wherein the at least one scintillation camera is placed at the determined position during the radiation treatment.

11 . A system for emission-guided radiation therapy (EGRT), comprising:
a scintillation camera directed at a region of interest (ROI) of a subject who is receiving a radiation treatment, wherein the subject is injected with a radioactive tracer or implanted with a radioactive marker before the radiation treatment, the ROI undergoes a physiological motion during the radiation treatment, and the scintillation camera is configured to detect single photons from annihilation photon pairs produced by interactions between the radioactive tracer or the radioactive marker and the subject; and a processing device configured to adaptively adjust, based on the single photons detected by the scintillation camera instead of coincidence events produced by the interactions, the delivery of the radiation treatment with respect to the physiological motion of the ROI.

12 . The system of claim 11 , the at least one scintillation camera includes one scintillation camera.

13 . The system of claim 12 , wherein the scintillation camera is mounted at a position, at which an angle between a trajectory of the radiation beam and a line connecting the scintillation camera and an isocenter of a radiotherapy device is equal to 90 degrees.

14 . The system of claim 11 , wherein the at least one scintillation camera includes two scintillation cameras mounted at their respective positions at which an angle between a trajectory of the radiation beam and a line connecting each scintillation camera and an isocenter of a radiotherapy device is equal to 45 degrees.

15 . The system of claim 11 , wherein to adaptively adjust, based on the single photons detected by the scintillation camera, the delivery of the radiation treatment with respect to the physiological motion of the ROI, the processing device is configured to:
obtain a plurality of reference images of the ROI corresponding to a plurality of motion phases of the ROI, each of the reference images being indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI at a corresponding motion phase; and adaptively adjust, based on the single photons detected by the scintillation camera and the plurality of reference images, the delivery of a radiation beam with respect to the physiological motion of the ROI.

16 . A system for emission-guided radiation therapy (EGRT), comprising:
a scintillation camera directed at a region of interest (ROI) of a subject who is receiving a radiation treatment, wherein the subject is injected with a radioactive tracer or implanted with a radioactive marker before the radiation treatment, the ROI undergoes a physiological motion during the radiation treatment, and the scintillation camera is configured to collect a target image of the ROI indicative of a distribution of the radioactive tracer or the radioactive maker in the ROI by detecting single photon events produced by interactions between the radioactive tracer or the radioactive marker and the subject; and a processing device configured to adaptively adjust, based on the target image collected by the scintillation camera, the delivery of the radiation treatment with respect to the physiological motion of the ROI.

17 . The system of claim 16 , the at least one scintillation camera includes one scintillation camera.

18 . The system of claim 17 , wherein the scintillation camera is mounted at a position, at which an angle between a trajectory of the radiation beam and a line connecting the scintillation camera and an isocenter of a radiotherapy device is equal to 90 degrees.

19 . The system of claim 16 , wherein the a

Assignees

• Shanghai United Imaging Healthcare Co Ltd

Inventors

• Maltz Jonathan

Classifications

• G06T12/10

  Image preprocessing, e.g. calibration, positioning of sources or scatter correction · CPC title

• G06T7/0016 Primary

  involving temporal comparison · CPC title

• A61N2005/1059

  using cameras imaging the patient · CPC title

• A61N2005/1052

  using positron emission tomography [PET] single photon emission computer tomography [SPECT] imaging · CPC title

• A61N2005/1051

  using an active marker · CPC title