Computerized tomography (CT) imaging system with multi-slit rotatable collimator
Apparatus for collimating an X-ray beam, the apparatus including a multi-slit rotatable collimator including a semi-tubular structure extending coaxially along a longitudinal axis and being formed out of an X-ray impermeable material, with at least two slits formed in the semi-tubular structure, wherein the at least two slits extend parallel to the longitudinal axis of the semi-tubular structure, a mount for rotatably supporting the semi-tubular structure in the path of an X-ray beam, and a drive mechanism for selectively rotating the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (i) position one slit in the path of the X-ray beam so as to tailor the X-ray beam to the width of that slit, and (ii) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam.
1. Apparatus for collimating an X-ray beam, the apparatus comprising:
a multi-slit rotatable collimator comprising:
a semi-tubular structure extending coaxially along a longitudinal axis, the semi-tubular structure being formed out of an X-ray impermeable material;
at least two slits formed in the semi-tubular structure, wherein the at least two slits extend parallel to the longitudinal axis of the semi-tubular structure;
a mount for rotatably supporting the semi-tubular structure in the path of an X-ray beam; and
a drive mechanism for selectively rotating the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (i) position one of the at least two slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of that slit, and (ii) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein the semi-tubular structure comprises two slits, and further wherein the drive mechanism is adapted to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (a) position a first of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the first of the slits, (b) position the second of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the second of the slits, and (c) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein one of the two slits has a width greater than the other of the two slits; and
wherein one of the two slits has a width configured to provide one of an 8 slice scan and a 32 slice scan.
2. Apparatus according to claim 1 wherein one of the two slits has a width configured to provide an 8 slice scan.
3. Apparatus according to claim 2 wherein the other of the two slits has a width configured to provide a 32 slice scan.
4. Apparatus according to claim 1 wherein the drive mechanism comprises a Geneva drive mechanism.
5. Apparatus according to claim 1 further comprising a position sensor for determining the rotational disposition of the semi-tubular structure relative to the mount.
6. Apparatus according to claim 1 further comprising a filter, wherein the filter is interposed between the X-ray beam and the semi-tubular structure.
7. Apparatus according to claim 6 wherein the filter comprises a bow-tie filter.
8. Apparatus for imaging a patient, the apparatus comprising:
a CT machine comprising an X-ray source; and
a multi-slit rotatable collimator comprising:
a semi-tubular structure extending coaxially along a longitudinal axis, the semi-tubular structure being formed out of an X-ray impermeable material;
at least two slits formed in the semi-tubular structure, wherein the at least two slits extend parallel to the longitudinal axis of the semi-tubular structure;
a mount for rotatably supporting the semi-tubular structure in the path of the X-ray beam; and
a drive mechanism for selectively rotating the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (i) position one of the at least two slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of that slit, and (ii) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein the semi-tubular structure comprises two slits, and further wherein the drive mechanism is adapted to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (a) position a first of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the first of the slits, (b) position the second of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the second of the slits, and (c) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein one of the two slits has a width greater than the other of the two slits; and
wherein one of the two slits has a width configured to provide one of an 8 slice scan and a 32 slice scan.
9. Apparatus according to claim 8 wherein one of the two slits has a width configured to provide an 8 slice scan.
10. Apparatus according to claim 9 wherein the other of the two slits has a width configured to provide a 32 slice scan.
11. Apparatus according to claim 8 wherein the drive mechanism comprises a Geneva drive mechanism.
12. Apparatus according to claim 8 further comprising a position sensor for determining the rotational disposition of the semi-tubular structure relative to the mount.
13. Apparatus according to claim 8 further comprising a filter, wherein the filter is interposed between the X-ray beam and the semi-tubular structure.
14. Apparatus according to claim 13 wherein the filter comprises a bow-tie filter.
15. A method for collimating an X-ray beam, the method comprising:
providing a multi-slit rotatable collimator comprising:
a semi-tubular structure extending coaxially along a longitudinal axis, the semi-tubular structure being formed out of an X-ray impermeable material;
at least two slits formed in the semi-tubular structure, wherein the at least two slits extend parallel to the longitudinal axis of the semi-tubular structure;
a mount for rotatably supporting the semi-tubular structure in the path of an X-ray beam; and
a drive mechanism for selectively rotating the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (i) position one of the at least two slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of that slit, and (ii) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein the semi-tubular structure comprises two slits, and further wherein the drive mechanism is adapted to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (a) position a first of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the first of the slits, (b) position the second of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the second of the slits, and (c) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam;
wherein one of the two slits has a width greater than the other of the two slits; and
wherein one of the two slits has a width configured to provide one of an 8 slice scan and a 32 slice scan;
providing an X-ray beam; and
using the drive mechanism to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure.
16. A method for imaging a patient, the method comprising:
providing a CT machine comprising an X-ray source, and a multi-slit rotatable collimator comprising a semi-tubular structure extending coaxially along a longitudinal axis, the semi-tubular structure being formed out of an X-ray impermeable material; at least two slits formed in the semi-tubular structure, wherein the at least two slits extend parallel to the longitudinal axis of the semi-tubular structure; a mount for rotatably supporting the semi-tubular structure in the path of the X-ray beam; and a drive mechanism for selectively rotating the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (i) position one of the at least two slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of that slit, and (ii) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam; wherein the semi-tubular structure comprises two slits, and further wherein the drive mechanism is adapted to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure, whereby to selectively (a) position a first of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the first of the slits, (b) position the second of the slits in the path of the X-ray beam so as to tailor the X-ray beam to the width of the second of the slits, and (c) position a solid portion of the semi-tubular structure in the path of an X-ray beam so as to block an X-ray beam; wherein one of the two slits has a width greater than the other of the two slits; and wherein one of the two slits has a width configured to provide one of an 8 slice scan and a 32 slice scan;
using the drive mechanism to selectively rotate the semi-tubular structure about the longitudinal axis of the semi-tubular structure; and
scanning the patient using the CT machine.