Non-linear correlation models for internal target movement
A method and apparatus to track non-linear internal target movement based on movement of an external marker.
1. A computer-implemented method, comprising:
receiving a plurality of data points representative of a corresponding plurality of positions over time of an external marker associated with respiration of a patient;
receiving a plurality of images of an internal target of the patient, the plurality of images corresponding in time to the plurality of data points;
developing, using a processing device, a non-linear correlation model of a non-linear path of movement of the target based on the plurality of data points and the plurality of images to correlate a plurality of positions of the internal target with the plurality of positions of the external marker, wherein developing the non-linear correlation model comprises:
generating an inspiration approximation associated with the non-linear path of movement of the target over an inspiration interval of the non-linear path;
generating an expiration approximation associated with the non-linear path of movement of the target over an expiration interval of the non-linear path; and
generating one or more matching approximations to link the inspiration approximation and the expiration approximation.
2. The method of claim 1 , wherein the non-linear correlation model comprises a polynomial approximation of the non-linear path of movement of the target.
3. The method of claim 1 , wherein the non-linear correlation model comprises a multi-linear model having a plurality of linear approximations connected at a non-zero angle.
4. The method of claim 1 , wherein developing the non-linear correlation model comprises generating one or derivatives from the plurality of data points, the one or more derivatives comprising one or more directional indicators.
5. The method of claim 1 , wherein the inspiration approximation and the expiration approximation are derived from at least partially overlapping data sets.
6. The method of claim 1 , further comprising deriving a target position of the target based on the non-linear correlation model.
7. The method of claim 6 , further comprising:
sending a position signal associated with the target position to a beam generator controller; and
controlling a beam generator to direct a beam at the target position.
8. The method of claim 1 , wherein the non-linear correlation model comprises a two-dimensional model or a three-dimensional model.
9. An apparatus, comprising:
a data storage device to store a plurality of data points representative of a corresponding plurality of positions over time of an external marker, the data storage device to store a plurality of images of an internal target of the patient, the plurality of images corresponding in time to the plurality of data points; and
a processing device coupled to the data storage device, the processing device configured to:
develop a non-linear correlation model of a non-linear path of movement of the target based on the plurality of data points and the plurality of images to correlate a plurality of positions of the internal target with the plurality of positions of the external marker, wherein developing the non-linear correlation model comprises:
generate an inspiration approximation associated with the non-linear path of movement of the target over an inspiration interval of the non-linear path;
generate an expiration approximation associated with the non-linear path of movement of the target over an expiration interval of the non-linear path; and
generate one or more matching approximations to link the inspiration approximation and the expiration approximation.
10. The apparatus of claim 9 , wherein the non-linear correlation model comprises a polynomial approximation of the non-linear path of movement of the target.
11. The apparatus of claim 9 , wherein the non-linear correlation model comprises a multi-linear model having a plurality of linear approximations connected at a non-zero angle.
12. The apparatus of claim 9 , wherein developing the non-linear correlation model comprises generating one or derivatives from the plurality of data points, the one or more derivatives comprising one or more directional indicators.
13. The apparatus of claim 9 , wherein the inspiration approximation and the expiration approximation are derived from at least partially overlapping data sets.
14. The apparatus of claim 9 , further comprising:
a beam generator controller operatively coupled with processing device, wherein the processing device is further configured to derive a target position of the target based on the non-linear correlation model and sending a position signal associated with the target position to the beam generator controller;
a beam generator operatively coupled with the beam generator controller to direct a beam at the target position.
15. A non-transitory machine readable storage medium having instructions thereon, which when executed by a processing device, cause the processing device to perform one or more operations comprising:
receiving a plurality of data points representative of a corresponding plurality of positions over time of an external marker associated with respiration of a patient;
receiving a plurality of images of an internal target of the patient, the plurality of images corresponding in time to the plurality of data points;
developing, using a processing device, a non-linear correlation model of a non-linear path of movement of the target based on the plurality of data points and the plurality of images to correlate a plurality of positions of the internal target with the plurality of positions of the external marker, wherein developing the non-linear correlation model comprises:
generating an inspiration approximation associated with the non-linear path of movement of the target over an inspiration interval of the non-linear path;
generating an expiration approximation associated with the non-linear path of movement of the target over an expiration interval of the non-linear path; and
generating one or more matching approximations to link the inspiration approximation and the expiration approximation.
16. The non-transitory machine readable storage medium of claim 15 , wherein the non-linear correlation model comprises a polynomial approximation of the non-linear path of movement of the target.
17. The non-transitory machine readable storage medium of claim 15 , wherein the non-linear correlation model comprises a multi-linear model having a plurality of linear approximations connected at a non-zero angle.
18. The non-transitory machine readable storage medium of claim 15 , wherein developing the non-linear correlation model comprises generating one or derivatives from the plurality of data points, the one or more derivatives comprising one or more directional indicators.
19. The non-transitory machine readable storage medium of claim 15 , wherein the inspiration approximation and the expiration approximation are derived from at least partially overlapping data sets.
20. The non-transitory machine readable storage medium of claim 15 , wherein the one or more operations further comprise deriving a target position of the target based on the non-linear correlation model.
21. The non-transitory machine readable storage medium of claim 20 , wherein the one or more operations further comprise:
sending a position signal associated with the target position to a beam generator controller; and
controlling a beam generator to direct a beam at the target position.