Methods for tumor tracking

Patent metadata

Field	Value
Publication number	US-12582845-B2
Application number	US-202318311069-A
Country	US
Kind code	B2
Filing date	May 2, 2023
Priority date	Nov 4, 2020
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

Disclosed herein are methods for determining the location of a moving target region (e.g., a tumor) based on the location of the center of its range of motion and the location of a target region surrogate, during a radiotherapy treatment session or a quality assurance (QA) session. These methods comprise characterizing the motion range of the target region, calculating the location of the center of the motion range, and determining a correlation between the position of the target region surrogate and the displacement of the target region from the center of the motion range as the target region moves.

First claim

The invention claimed is:

1 . A method for determining a target region location comprising:
using acquired imaging data to calculate a center of motion location of a target region; acquiring position data from a target region surrogate; determining a displacement shift vector of the target region from the center of motion location based on the target region surrogate position data; and calculating a target region location by combining the center of motion location with the displacement shift vector.

2 . The method of claim 1 , wherein the target region is a tumor.

3 . The method of claim 1 , wherein the target region surrogate comprises a breathing surrogate.

4 . The method of claim 1 , wherein the target region surrogate comprises one or more of: an infrared reflector block, an implantable RF-emitting fiducial marker, and a radiation-emitting source.

5 . The method of claim 4 , wherein the radiation-emitting source is an X-ray emitting source and acquiring position data comprises acquiring X-ray detector data.

6 . The method of claim 4 , wherein the radiation-emitting source is a photon-emitting source and acquiring position data comprises acquiring single-photon emission detector data.

7 . The method of claim 4 , wherein the radiation-emitting source is a positron-emitting source and acquiring position data comprises acquiring PET detector data.

8 . The method of claim 1 , wherein acquiring position data comprises acquiring optical camera images of a patient's skin surface.

9 . The method of claim 1 , wherein the acquired imaging data comprises one or more of X-ray, SPECT, MRI, and/or PET imaging data.

10 . The method of claim 9 , wherein calculating the center of motion location comprises acquiring imaging data over an interval of time to define a range of motion of the target region.

11 . The method of claim 10 , wherein the interval of time includes multiple periods of a breathing cycle.

12 . The method of claim 10 , wherein the imaging data comprises imaging data of the target region.

13 . The method of claim 12 , wherein the imaging data comprises imaging data of the target region surrogate.

14 . The method of claim 10 , wherein calculating the center of motion location ( X , Y , Z ) further comprises sectioning the motion range into a number N of location bins (X i , Y i , Z i ), calculating a dwell-time (t i ) of the target region within each location bin, and calculating the center of motion location by calculating the average location of the target region using the dwell-time of the target region within each location bin (X i , Y i , Z i )

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15 . The method of claim 10 , wherein the interval of time is about 10 minutes or less.

16 . The method of claim 15 , wherein the interval of time is about 3 minutes or less.

17 . The method of claim 16 , wherein the interval of time is about 1 minute or less.

18 . The method of claim 14 , wherein defining the motion range of the target region uses 4-D imaging data.

19 . The method of claim 18 , wherein 4-D imaging data comprises 4-D PET/CT imaging data.

20 . The method of claim 1 , further comprising calculating a coefficient based on a target region motion amplitude and a target region surrogate motion amplitude, and wherein determining the displacement shift vector comprises scaling the position data by the coefficient.

21 . The method of claim 20 , wherein calculating the coeffic

Assignees

• Reflexion Medical Inc

Inventors

• Bassalow Rostem
• Zdasiuk George Andrew

Classifications

• 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

• A61B6/037

  Emission tomography · CPC title

• A61N5/1067

  in real time, i.e. during treatment · CPC title