1. A method for registering a patient’s body part in a medical workspace of a medical navigation system, wherein said body part is supported by at least one support device, comprising:
obtaining at least two x-ray or fluoroscopic recordings of the body part, wherein the at least one support device is situated in a radiation path of an x-ray or fluoroscopic recording apparatus during recordation of the at least two x-ray or fluoroscopic recordings;
using the medical navigation system to ascertain a position of the at least one support device and of the x-ray or fluoroscopic apparatus during recordation of the at least two x-ray or fluoroscopic recordings;
using the ascertained position of the at least one support device and the x-ray or fluoroscopic apparatus to identify an image of the at least one support device in the at least two x-ray or fluoroscopic recordings;
using the at least two recordings to register the body part in the medical workspace, wherein image data corresponding to the image of the at least one support device are not used to register the body part.
2. The method according to claim 1, wherein ascertaining a position of the at least one support device includes:
attaching a reference device to the at least one support device; and
using the navigation system to track a position of the reference device.
3. The method according to claim 1, wherein ascertaining a position of the at least one support device includes using known geometric data of the at least one support device to ascertain said position.
4. The method according to claim 3, wherein using known geometric data includes retrieving geometric data of the at least one support device from memory of the medical navigation system.
5. The method according to claim 1, wherein using the at least two recordings to register the body part includes subtracting the image data of the of the at least one support device from the at least two recordings.
6. The method according to claim 1, wherein image data corresponding to the image of the at least one support device includes image contours of the at least one support device.
7. The method according to claim 1, wherein identifying the image of the at least one support device includes using known grey values generated in the at least two recordings as an aid for identifying the image of the at least one support device.
8. The method according to claim 1, wherein identifying the image of the at least one support device includes using known distances between support elements of the at least one support device as an identification aid.
9. The method according to claim 1, wherein identifying the image of the at least one support device includes using known distances between support elements of the at least one support device and markers attached to the support device as identification aids.
10. The method according to claim 1, wherein identifying the image of the at least one support device includes using known distances between support elements of the at least one support device and connecting lines of specific markers in or on the support as identification aids.
11. A system for registering a patient’s body part in a medical workspace of a medical navigation system, wherein said body part is supported by at least one support device, comprising:
a medical navigation system including a processor and memory;
a reference device coupled to said at least one support device;
a tracking device communicatively coupled to said medical navigation system and operative to determine a position of said reference device;
an x-ray or fluoroscopic apparatus for capturing x-ray or fluoroscopic images of the body part; and
logic stored in said memory and executable by said processor, said logic including logic that eliminates an effect of image artefacts on registration of the body part, wherein said artefacts are caused by said at least one support device.
12. The system according to claim 11, wherein said logic that eliminates the effect of image artefacts includes:
logic that ascertains a position of the at least one support device and of the x-ray or fluoroscopic apparatus during image capture;
logic that uses the ascertained position of the at least one support device and of the x-ray or fluoroscopic apparatus to identify an image of the at least one support device in the captured image; and
logic that prior to registration removes the image data corresponding to the at least one support device from the captured image data.
13. The system according to claim 11, wherein geometric data of the at least one support device are stored in said memory.
14. The system according to claim 11, wherein the at least one support device consists of a material that is permeable to x-ray radiation.
15. The system according to claim 12, further comprising at least one marker arranged on the at least one support device at known locations relative to support elements of the at least one support device, said at least one marker comprising a material that is substantially impermeable to x-ray radiation.
16. A computer program stored on a machine readable medium for registering a patient’s pelvis in a medical workspace of a medical navigation system, wherein said pelvis is supported by at least one support device, comprising:
code that directs the acquisition of at least two x-ray or fluoroscopic recordings of the body part, wherein the at least one support device is situated in a radiation path of an x-ray or fluoroscopic recording apparatus during recordation of the at least two x-ray or fluoroscopic recordings;
code that ascertains a position of the at least one support device and of the x-ray or fluoroscopic apparatus during recordation of the at least two x-ray or fluoroscopic recordings;
code that uses the ascertained position of the at least one support device and the x-ray or fluoroscopic apparatus to identify an image of the at least one support device in the at least two x-ray or fluoroscopic recordings;
code that uses the at least two recordings to register the body part in the medical workspace, wherein image data corresponding to the image of the at least one support device are not used to register the body part.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An optical system comprising:
a first subsystem comprising:
a first reflecting optical component;
at least one other reflecting optical component optically disposed to provide, for an input beam of electromagnetic radiation, a plurality of propagation paths between said first reflecting optical component and said at least one other reflecting optical component;
a first pixellated volume holographic switchable element optically disposed between said first reflecting optical component and said at least one other reflecting optical component; and
a second subsystem comprising:
a second reflecting optical component;
at least one other second reflecting optical component optically disposed to provide, for an incoming beam of electromagnetic radiation, a plurality of propagation paths between said second reflecting optical component and said at least one other reflecting optical component;
a second pixellated volume holographic switchable element optically disposed between said second reflecting optical component and said at least one other second reflecting optical component;
said first pixellated volume holographic switchable element being capable of directing electromagnetic radiation, from said first sub-system, to said second pixellated switchable element;
said second pixellated volume holographic switchable element being capable of directing received electromagnetic radiation to said second reflecting optical component or said at least one other reflecting optical component of the second subsystem.
2. The optical system of claim 1 further comprising:
an imaging optical element optically disposed between said first reflecting optical component and said first pixellated volume holographic switchable element.
3. The optical system of claim 1 further comprising:
an imaging optical element optically disposed between said at least one other reflecting optical component and said first pixellated volume holographic switchable element.
4. The optical system of claim 1 further comprising:
an imaging optical element optically disposed between said second reflecting optical component and said second pixellated volume holographic switchable element.
5. The optical system of claim 1 further comprising:
an imaging optical element optically disposed between said at least one other reflecting optical component of the second subsystem and said second pixellated volume holographic switchable element.
6. The optical system of claim 1 further comprising:
an imaging optical element optically disposed between said first said first pixellated volume holographic switchable element and said second pixellated volume holographic switchable element.
7. The optical system of claim 1 further comprising:
a variable optical path length element optically disposed to intersect at least some of the plurality of propagation paths in said first subsystem.
8. The optical system of claim 1 further comprising:
a variable optical path length element optically disposed to intersect at least some of the plurality of propagation paths in said second subsystem.
9. The optical system of claim 1 wherein said first pixellated switchable element comprises a first pixellated volume holographic switchable volume holographic transmission grating, and said second pixellated volume holographic switchable element comprises a second pixellated switchable volume holographic transmission grating.
10. The optical system of claim 1 wherein said first pixellated volume holographic switchable element comprises a first pixellated switchable volume holographic reflection grating, and said second pixellated volume holographic switchable element comprises a second pixellated switchable volume holographic reflection grating.
11. An optical system comprising:
a first plurality of reflecting optical components;
a second plurality of reflecting optical components;
a pixellated switchable volume reflecting element optically disposed between said first plurality of reflecting optical components and said second pluralities of reflecting optical components;
a first imaging optical element optically disposed between said first plurality of reflecting optical components and said pixellated switchable volume reflecting element; and
a second imaging optical element optically disposed between said second plurality of reflecting optical elements and said pixellated switchable volume reflecting element;
said first plurality of reflecting optical components being optically disposed to provide, for an input beam of electromagnetic radiation, a plurality of propagation paths between said first plurality of reflecting optical components and said pixellated switchable volume reflecting element;
said first plurality of reflecting optical components, said first imaging optical element and said pixellated switchable volume reflecting element comprising a first sub-system;
said second plurality of reflecting optical components being optically disposed to provide, for another input beam of electromagnetic radiation, a plurality of propagation paths between said second plurality of reflecting optical components and said pixellated switchable volume reflecting element;
said second plurality of reflecting optical components, said second imaging optical element and said pixellated switchable volume reflecting element comprising a second sub-system;
said pixellated switchable volume reflecting element being capable of transmitting electromagnetic radiation from said first sub-system to said second sub-system and being also capable of transmitting electromagnetic radiation from said second sub-system to said first sub-system, when said pixellated switchable volume reflecting element is a transmissive state.
12. The optical system of claim 11 further comprising:
a variable optical path length element optically disposed to intersect at least some of the plurality of propagation paths in said first subsystem.
13. The optical system of claim 11 further comprising:
a variable optical path length element optically disposed to intersect at least some of the plurality of propagation paths in said second subsystem.