Method and apparatus for controlling X-ray exposure
The present invention pertains to an apparatus and method for adaptive exposure in imaging systems. An x-ray source for producing x-ray radiation and an x-ray detector for measuring amount of x-ray radiation passing through the human patient and striking the detector can be used. A tomographic image of the human patient or a tomosynthetic image of the human patient can be generated. Region of interest filtering and equalization filtering can be utilized. Filtering can be accomplished with a mechanical shield or shutter or with electronic control of the x-ray source.
1. A method for producing an x-ray image of a human patient comprising:
producing a beam of x-ray radiation from an x-ray source;
selecting a region of interest in said human patient;
controlling said beam to reduce said x-ray radiation emitted from areas of said x-ray source corresponding to areas outside said region of interest in said patient; and
measuring amount of said x-ray radiation passing through said human patient and striking a detector.
2. The method of claim 1 further comprising:
selecting a second region of interest in said human patient.
3. The method of claim 2 further comprising:
reducing said x-ray radiation to areas outside said region of interest and said second region of interest.
4. The method of claim 2 further comprising:
reducing said x-ray radiation to said second region of interest in said human patient.
5. The method of claim 1 further comprising:
limiting said x-ray radiation to said region of interest in said human patient to a minimum amount required to achieve a specified signal-to-noise ratio.
6. The method of claim 1 further comprising:
limiting said x-ray radiation to said region of interest in said human patient to a minimum amount required to achieve a specified resolution.
7. The method of claim 1 further comprising:
limiting said x-ray radiation to areas outside said region of interest in said human patient to a minimum amount required to achieve a specified signal-to-noise ratio.
8. The method of claim 1 further comprising:
limiting said x-ray radiation to areas outside said region of interest in said human patient to a minimum amount required to achieve a specified resolution.
9. The method of claim 1 further comprising:
limiting said x-ray radiation to said region of interest in said human patient to a specified amount and less.
10. The method of claim 1 further comprising:
terminating delivery of said x-ray radiation to said region of interest in said patient when said x-ray radiation to said region of interest reaches a predetermined threshold amount.
11. The method of claim 1 further comprising:
selecting exposure of said x-ray radiation for each of a plurality of projections of said region of interest.
12. The method of claim 1 further comprising:
reducing said x-ray radiation to areas outside said region of interest in said patient by decreasing an individual exposure time of said beam.
13. The method of claim 1 further comprising:
reducing said x-ray radiation to areas outside said region of interest in said patient by decreasing a total number of exposures of said beam.
14. The method of claim 1 further comprising:
adjusting said beam based on attenuation characteristics.
15. The method of claim 1 further comprising:
compressing dynamic range by reducing said x-ray radiation to a translucent area in said human patient.