Fixtures for fluoroscopic imaging systems and related navigation systems and methods

A fixture for a fluoroscopic x-ray imaging system, wherein the fluoroscopic x-ray imaging system includes a C-arm, an x-ray source at a first end of the C-arm, and an x-ray detector at a second end of the C-arm, the fixture comprising:

• a processor;
• and
• memory coupled with the processor, wherein the memory includes instructions that are executable by the processor so that the fixture is configured to,
• detect an x-ray emission from the x-ray source toward the x-ray detector,
• determine an offset of the x-ray source relative to the x-ray detector, responsive to detecting the x-ray emission, and
• provide an indication of the offset of the x-ray source to a medical navigation system.

A medical navigation system comprising:

• a processor;
• and
• memory coupled with the processor wherein the memory includes instructions that are executable by the processor so that the medical navigation system is configured to,
• receive information defining a first image from a fluoroscopic x-ray imaging system, wherein the fluoroscopic x-ray imaging system includes a C-arm, an x-ray source at a first end of the C-arm, and an x-ray detector at a second end of the C-arm,
• provide an indication of a first offset of the x-ray source relative to the x-ray detector, wherein the first offset is associated with the first image,
• receive information defining a second image from the fluoroscopic x-ray imaging system, wherein the first image and the second image are different,
• provide an indication of a second offset of the x-ray source relative to the x-ray detector, wherein the second offset is associated with the second image, and wherein the first offset and the second offset are different, and
• provide a registration between a tracking coordinate system for a physical space monitored by tracking sensors and an image coordinate system for the first and second images from the fluoroscopic x-ray imaging system, wherein the registration is provided based on the indications of the first offset and the second offset.