3D real-time tracking of human anatomy using combined kV and MV imaging
View Patent ↗A medical imaging-based system and method uses both kV and MV images captured during a treatment period for organ motion tracking. 3D geometric locations of internal features are computationally tracked as a function of time from internal features, such as natural biological features or implanted fiducials, which are computationally extracted from the captured kV and MV images. A partial information method allows 3D tracking to be maintained in the event that imaging information is temporarily not available.
1. A medical imaging-based method for organ motion tracking as a function of time, the method comprising:
capturing kV images during a treatment period using a kV imaging detector;
capturing MV images during the treatment period using an MV radiotherapy beam imaging detector;
extracting 2D kV projection locations of internal features from the captured kV images;
extracting 2D MV projection locations of the internal features from the captured MV images;
combining the extracted 2D kV projection locations and extracted 2D MV projection locations with information describing geometry of the kV imaging detector and MV radiotherapy beam imaging detector to calculate 3D locations of the internal features; and
computationally tracking 3D geometric locations of the internal features as a function of time from the 3D locations of the internal features and information of previous positions of the internal features.
2. The method of claim 1 wherein the capturing kV images comprises capturing the kV images continuously during the treatment period.
3. The method of claim 1 wherein the capturing kV images comprises capturing the kV images intermittently during the treatment period.
4. The method of claim 1 wherein the internal features are natural biological features.
5. The method of claim 1 wherein the internal features are implanted fiducials.
6. The method of claim 1 wherein the kV imaging detector is a kV diagnostic imaging detector.
7. The method of claim 1 wherein computationally tracking comprises using a partial information method.
8. A medical imaging system comprising:
a) kV and MV beam generators for generating kV and MV beams;
b) kV and MV x-ray detector arrays for detecting the kV and MV beams;
c) an image grabber to capture kV images and MV images acquired using the x-ray detector arrays, and
d) a computer for extracting 2D kV projection locations of the internal features from the kV images, extracting 2D MV projection locations of the internal features from the MV images, combining the extracted 2D kV projection locations and extracted 2D MV projection locations with information describing geometry of the kV imaging detector and MV radiotherapy beam imaging detector to calculate 3D locations of the internal features, computing continuous 3D geometric locations of internal features as a function of time from the 3D locations of the internal features and information of previous positions of the internal features.
9. The method of claim 8 wherein the kV and MV x-ray detectors are flat panel detectors.
10. The method of claim 8 wherein the image grabber is a hardware frame grabber.