Tomographic imaging with motion detection system
A tomographic imaging system comprises a support carrying an image data acquisition system and defining a reference coordinate frame. A scan plan control sets the image-data acquisition system to acquire image-data from a selected imaging zone in the reference coordinate system. A motion detection system to detect movement and includes (i) a dynamic camera system to receive dynamic image information registered in the image coordinate frame of the dynamic camera system, (ii) an arithmetic unit configured to transform the selected imaging zone from the reference coordinate frame to the image coordinate-frame and a (iii) motion analyser to derive motion information from the registered dynamic image information in the transformed selected imaging zone. In the event of motion detected by the motion analyser in or near the imaging zone, the detected motion may be employed for motion correction.
1. A tomographic imaging system, comprising:
a support carrying a tomographic image-data acquisition system and defining a reference coordinate frame;
a scan plan control to set the tomographic image-data acquisition system to acquire tomographic image-data from a selected imaging zone in the reference coordinate system;
a motion detection system to detect movement and comprising:
a dynamic camera system to receive dynamic image information registered in the image coordinate frame of the dynamic camera system;
an arithmetic unit configured to transform the selected imaging zone from the reference coordinate frame to the image-coordinate-frame;
a motion analyser to derive motion information from the registered dynamic image information in the transformed selected imaging zone, wherein the motion detection system has access to a volumetric outline, from survey scan-data or from the dynamic camera system, including the selected imaging zone in the reference coordinate-frame;
a region-analyser to determine within the selected imaging zone in the reference coordinate-frame a zone of interest of the volumetric outline within the selected imaging zone, wherein the arithmetic unit configured to transform the zone-of-interest from the reference coordinate system onto the image coordinate-frame of the dynamic camera system, thus determining a transformed zone of interest; and
a camera control to set the acquisition of the dynamic camera system to acquire dynamic image information from at least the determined transformed zone of interest, wherein the motion-analyser is set to predominantly derive motion from the dynamic image information from the transformed zone of interest.
2. The tomographic imaging system of claim 1 , further including a gantry that defines the reference coordinate frame.
3. The tomographic imaging system of claim 1 , wherein the dynamic camera system is mounted to the support such that at least a portion of the selected imaging zone is in the dynamic camera system's range.
4. The tomographic imaging system of claim 1 , wherein the motion detection system is provided with a depth-camera to acquire the volumetric outline.
5. The tomographic imaging system of claim 3 , wherein the depth-camera is part of the dynamic camera system.
6. The tomographic imaging system of claim 1 , wherein the arithmetic unit is further configured to transform the derived or acquired volumetric outline to the reference coordinate-frame defined by the support.
7. A method of motion detection of a subject during tomographic imaging, the method comprising:
selecting an imaging zone to be tomographically imaged;
acquiring tomographic image-data from the selected imaging zone in a reference coordinate system;
receiving dynamic image information registered in a dynamic camera system's image coordinate frame;
projecting at least a portion of the selected imaging zone from the reference coordinate frame onto the image coordinate frame;
deriving motion information from the registered dynamic image information in the projected selected imaging zone;
accessing in the reference coordinate frame a volumetric outline of the subject to be tomographically imaged;
determining a zone of interest of one or more portions of interest of the volumetric outline within the selected imaging zone;
transforming the zone of interest from the reference coordinate frame onto the image coordinate frame of the dynamic camera system, thus determining a transformed zone of interest; and
deriving motion from the dynamic image information predominantly in the transformed zone of interest.
8. The method of claim 7 , wherein the dynamic camera system is mounted to the support such that at least a portion of the selected imaging zone is in the dynamic camera system's range.
9. The method of claim 7 , wherein the motion detection system is provided with a depth-camera to acquire the volumetric outline.
10. The method of claim 9 , wherein the depth-camera is part of the dynamic camera system.
11. The method of claim 7 , further comprising transforming the derived or acquired volumetric outline to the reference coordinate frame defined by the support.
12. A tangible, non-transitory computer readable medium that stores instructions, which when executed by a processor, cause the processor to:
select an imaging zone to be tomographically imaged acquiring tomographic image-data from the selected imaging zone in a reference coordinate system;
receive dynamic image information registered in a dynamic camera system's image coordinate frame;
project at least a portion of the selected imaging zone from the reference coordinate frame onto the image coordinate frame;
derive motion information from the registered dynamic image information in the projected selected imaging zone;
access in the reference coordinate-frame a volumetric outline of the subject to be tomographically imaged;
determine a zone of interest of one or more portions of interest of the volumetric outline within the selected imaging zone;
transform the zone of interest from the reference coordinate frame onto the image coordinate frame of the dynamic camera system, thus determining a transformed zone of interest; and
derive motion from the dynamic image information predominantly in the transformed zone of interest.
13. The tangible, non-transitory computer readable medium of claim 12 , further including a gantry that defines the reference coordinate frame.
14. The tangible, non-transitory computer readable medium of claim 12 , wherein the dynamic camera system is mounted to the support such that at least a portion of the selected imaging zone is in the dynamic camera system's range.
15. The tangible, non-transitory computer readable medium of claim 12 , wherein the motion detection system is provided with a depth-camera to acquire the volumetric outline.
16. The tangible, non-transitory computer readable medium of claim 14 , wherein the depth-camera is part of the dynamic camera system.
17. The tangible, non-transitory computer readable medium of claim 12 , wherein the processor is further configured to transform the derived or acquired volumetric outline to the reference coordinate-frame defined by the support.