US 12,484,869 B2
Kalman filter framework to estimate 3D intrafraction motion from 2D projection
Doan Trang Nguyen, New South Wales (AU); Paul Keall, New South Wales (AU); and Ricky O'Brien, New South Wales (AU)
Assigned to SeeTreat PTY Ltd., Greenwich (AU)
Appl. No. 18/251,341
Filed by SEETREAT PTY LTD, Greenwich (AU)
PCT Filed Nov. 2, 2021, PCT No. PCT/IB2021/060107
§ 371(c)(1), (2) Date May 1, 2023,
PCT Pub. No. WO2022/097013, PCT Pub. Date May 12, 2022.
Claims priority of provisional application 63/109,898, filed on Nov. 5, 2020.
Prior Publication US 2023/0404504 A1, Dec. 21, 2023
Int. Cl. A61B 6/46 (2024.01); A61B 6/00 (2024.01); A61N 5/10 (2006.01); G06T 7/00 (2017.01); G06T 7/277 (2017.01); G06T 7/70 (2017.01)
CPC A61B 6/466 (2013.01) [A61B 6/5217 (2013.01); A61B 6/5264 (2013.01); A61N 5/1037 (2013.01); A61N 5/1049 (2013.01); A61N 5/1067 (2013.01); G06T 7/0012 (2013.01); G06T 7/277 (2017.01); G06T 7/70 (2017.01); A61B 2576/00 (2013.01); G06T 2207/10116 (2013.01); G06T 2207/30081 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method of estimating 3D target position during radiotherapy, the method comprising:
acquiring one or more two-dimensional (2D) image positions of one or more treatment targets or one or more surrogates from a (kilovoltage) kV imager on a linear accelerator;
implementing a Kalman filter framework using one or more computers to estimate a three-dimensional (3D) motion of the one or more treatment targets or the one or more surrogates from 2D image projection measurements in real-time during a radiotherapy treatment, wherein the Kalman filter is an iterative framework that allows for estimation of the measurement and estimation of a process error to be re-estimated from current and past measurements, wherein a population covariance of prostate motion is defined as:

OG Complex Work Unit Math
updating a target motion covariance with every image frame based on a last observed position of the one or more treatment targets or the one or more surrogates on a previous kV image; and
outputting to a display during the radiotherapy treatment the updated target motion.
 
5. A method of monitoring movement of an organ or portion of an organ or one or more surrogates of the organ during irradiation, comprising:
directing radiation energy at, at least a portion of an organ in a body part of a human or an animal subject;
imaging multiple two dimensional images of the organ from varying positions and varying angles relative to the body part;
digitally processing at least a plurality of the multiple two dimensional images using a one or more computers with a software application running a Kalman filter algorithm, wherein the digital processing is initialized with a population covariance matrix of prostate motion defined as

OG Complex Work Unit Math
displaying estimated three dimensional motion of the organ or portion of the organ in the body part based on output from the digital processing.