Virtual C-arm robotic positioning system for use in radiographic imaging equipment

• US 6,200,024 B1
• Filed: 11/27/1998
• Issued: 03/13/2001
• Est. Priority Date: 11/27/1998
• Status: Expired due to Fees

• Current Assignee: Picker International, Inc. (Marconi Holdings Company Limited)
• Original Assignee: Picker International, Inc. (Marconi Holdings Company Limited)
• Inventors: Negrelli, Donald E.
• Primary Examiner(s): Bruce, David V.
• Assistant Examiner(s): Dunn, Drew A.
• Application Number:
  US09/200,688
• Time in Patent Office: 837 Days
• Field of Search: 378/197, 378/198, 378/62, 378/196, 378/4
• US Class Current: 378/197
• CPC Class Codes: A61B 6/4233 using matrix detectors
• CPC Class Codes: A61B 6/4452 the source unit and the detector unit being able to move relative to each other
• CPC Class Codes: A61B 6/4458 the source unit or the detector unit being attached to robotic arms
• CPC Class Codes: A61B 6/4464 the source unit or the detector unit being mounted to ceiling
• CPC Class Codes: A61B 6/4476 related to motor-assisted motion of the source unit
• CPC Class Codes: A61B 6/587 Alignment of source unit to detector unit

Abstract

A virtual C-arm support system 40 is used in a radiographic imaging apparatus of the type including an x-ray source 44 and an x-ray detector 48. The support system includes a first positioning system 42 operatively connected to the x-ray source for selectively positioning the x-ray source in a range of first orientations 120, 140, 170 relative to the examination region E. A second positioning system 46 is operatively connected to the x-ray detector 48 for selectively positioning the x-ray detector in a range of second orientations 122, 142, 172 relative to the examination region E. A control unit 60 is in operative command of at least one of the first and second positioning systems to maintain a predetermined spatial relationship between the x-ray source and the detector for each of the ranges of the first and second orientations relative to the examination region. In a second embodiment, the control unit is in operative command of only the first positioning system, the second positioning system being manually movable. The control unit maintains a predetermined spatial relationship between the x-ray source and detector by moving the x-ray source in response to manual movement of the x-ray detector for each of the ranges of first and second orientations of the source and detector relative to the examination region.

Claims

1. A virtual C-arm support system for use in a radiographic imaging apparatus of the type including an x-ray source adapted to transmit an x-ray beam along a path through an examination region and an x-ray detector adapted to receive the x-ray beam and generate electric signals indicative of an intensity of the received x-ray beam, the virtual C-arm system comprising:

a first positioning system connected to the x-ray source for selectively positioning the x-ray source in a range of first orientations relative to the examination region;

a second positioning system connected to the x-ray detector for selectively positioning the x-ray detector in a range of second orientations relative to the examination region; and

,

a control unit in operative command of at least one of the first and second positioning systems to maintain a predetermined spatial relationship between the x-ray source and the x-ray detector for each of said ranges of first and second orientations relative to the examination region.

2. The virtual C-arm support system according to claim 1 wherein:

the first positioning system is responsive to a first command signal to move the x-ray source relative to the examination region based on the first command signal;

the second positioning system is responsive to a second command signal to move the x-ray detector relative to the examination region based on the second command signal; and

,

the control unit is in operative command of both the first positioning system and the second positioning system and is adapted to selectively generate said first and second command signals to respectively position the x-ray source and the x-ray detector at a plurality of sets of first and second positions in relative alignment with each other on opposite sides of the examination region so that at each of said plurality of sets of first and second positions, the x-ray beam transmitted from the x-ray source passes through the examination region and so that at each of said plurality of sets of first and second positions, the x-ray detector is disposed along said path of the x-ray beam to intercept the x-ray beam to generate said electric signals indicative of the intensity of the received x-ray beam.

3. The virtual C-arm support system according to claim 2 wherein:

the first positioning system is a first movable arm assembly having a first end held fixed at a first location relative to the examination region and a free end adapted for connection to the x-ray source, the first movable arm assembly being responsive to said first command signal from the control unit to selectively orient the x-ray source relative to the examination region; and

,

the second positioning system is a second movable arm assembly having a first end held fixed at a second location relative to the examination region and a free end adapted for connection to the x-ray detector, the second movable arm assembly being responsive to said second command signal from the control unit to selectively orient the x-ray detector relative to the examination region.

4. The virtual C-arm support system according to claim 3 wherein:

the control unit is adapted to generate first and second position command signals to selectively control said path of the x-ray beam transmitted through the examination region;

the first movable arm assembly includes a first multi-segmented robotic arm assembly having a closed loop servo positioning system cooperative with the first multi-segmented robot arm to selectively position the x-ray source in said plurality of first orientations relative to the examination region in response to said first position command signal from the control unit; and

,

the second movable arm assembly includes a second multi-segmented robot arm assembly having a closed loop servo positioning system cooperative with the second multi-segmented robotic arm to selectively position the x-ray detector in said plurality of second orientations relative to the examination region in response to said second position command signal from the control unit.

5. The virtual C-arm support system according to claim 4 wherein the control unit:

is responsive to an x-ray beam angulation signal received from an operatively associated external source to control said path of the x-ray beam by generating said first and second position command signals so that the path of the x-ray beam matches the x-ray beam angulation signal; and

,

is adapted to generate an x-ray beam path indicia signal representative of said path of the x-ray beam through the examination region.

6. The virtual C-arm support system according to claim 5 wherein:

the control unit is responsive to an x-ray beam angulation signal received from an operatively associated joystick operable by a human operator;

the first end of the first multi-segmented robotic arm assembly is floor supported and is held fixed relative to a patient table adjacent the examination region; and

,

the first end of the second multi-segmented robotic arm assembly is ceiling supported and is held fixed relative to the patient table adjacent the examination region.

7. A virtual C-arm support system for use in a radiographic imaging apparatus of the type including an x-ray source adapted to transmit an x-ray beam along a path through an examination region and an x-ray detector adapted to receive the x-ray beam and generate electric signals indicative of an intensity of the received x-ray beam, the virtual C-arm system comprising:

a first positioning system connected to the x-ray source for selectively positioning the x-ray source in a range of first orientations relative to the examination region, the first positioning system being responsive to a first command signal to move the x-ray source relative to the examination region based on the first command signal;

a second positioning system connected to the x-ray detector for selectively positioning the x-ray detector in a range of second orientations relative to the examination region, the second positioning system being adapted to generate an x-ray detector orientation feedback signal representative of the relative orientation between the x-ray detector carried on the second positioning system and said examination region; and

,

a control unit in operative command of at least one of the first and second positioning systems to maintain a predetermined spatial relationship between the x-ray source and the x-ray detector for each of said ranges of first and second orientations relative to the examination region, the control unit being in operative control of the first positioning system and adapted to selectively generate said first command signal used by the first positioning system to control the path of the x-ray beam transmitted through the examination region based on said x-ray detector feedback orientation signal to maintain said predetermined spatial relationship between the x-ray emitter and the x-ray detector.

8. The virtual C-arm support system according to claim 7 wherein:

the first positioning system is a first movable arm assembly having a first end held fixed at a first location relative to the examination region and a free end adapted for connection to the x-ray source, the first movable arm assembly being responsive to said first command signal from the control unit to selectively orient the x-ray source relative to the examination region; and

,

the second positioning system is a second movable arm assembly having a first end held fixed at a second location relative to the examination region and a free end adapted for connection to the x-ray detector, the second movable arm assembly being manually movable by a human operator to selectively orient the x-ray detector relative to the examination region.

9. A positioning system for an x-ray source and an x-ray detector in a radiographic imaging apparatus, the positioning apparatus comprising:

a first robotic support member having a first fixed end and a free end, the first robotic support member being responsive to a first position command signal to move the free end relative to the fixed end;

a second robotic support member having a fixed end and a free end, the second robotic support member being responsive to a second position command signal to move the free end relative to the fixed end;

an x-ray source carried on the first support member and adapted to transmit an x-ray beam along a path through an examination region;

an x-ray receptor carried on the second support member and adapted to receive the x-ray beam and generate electric signals indicative of an intensity of the received x-ray beam; and

,

a control unit operatively connected to the first robotic support member and the second robotic support member, the control unit being adapted to generate said first and second position command signals to move the first support member and the second support member into first and second positions, respectively, relative to the examination region, with a predetermined spatial relationship between the x-ray source and the x-ray detector, to enable the radiographic imaging apparatus to produce a radiographic image.

10. The positioning system according to claim 9 wherein the first and second robotic support members are adapted to move the x-ray source and the x-ray receptor through respective first and second arcuate paths to respective first and second positions relative to the examination region to enable the radiographic imaging apparatus to produce said radiographic image.

11. The positioning system according to claim 10 wherein the control unit is adapted to generate said first and second command signals to maintain a predetermined relative distance between the x-ray source and the x-ray receptor.

12. The positioning system according to claim 11 wherein the control unit is adapted to generate said first and second command signals in response to an x-ray beam angulation signal generated from an operatively associated external manual joystick device.

13. The positioning system according to claim 12 wherein the control unit is adapted to move the x-ray source and the x-ray receptor through said respective first and second arcuate paths to respective first and second positions to enable the radiographic imaging apparatus to produce a one of a left and right anterior oblique view of a human body disposed in said examination region.

14. The positioning system according to claim 12 wherein the control unit is adapted to move the x-ray source and the x-ray receptor through said respective first and second arcuate paths to respective first and second positions to enable the radiographic imaging apparatus to produce a one of a caudal and cranial view of a human body disposed in said examination region.

15. The positioning system according to claim 12 wherein the fixed end of the first robotic support member is carried on a support adapted to enable linear motion of the first robotic support member.

16. A diagnostic imaging apparatus comprising:

an x-ray source adapted to transmit an x-ray beam through an examination region;

an x-ray detector adapted to receive the x-ray beam and generate electric signals indicative of an intensity of the received x-ray beam;

a first mechanical arm assembly adapted to carry the x-ray detector, the first mechanical arm assembly being manually movable to hold the x-ray detector in a plurality of first positions relative to the examination region;

a second mechanical arm assembly adapted to carry the x-ray source, the second mechanical arm assembly being responsive to a motion command signal to selectively position the x-ray source at a plurality of second locations relative to the examination region; and

,

a control unit operatively associated with the first and second mechanical arm assemblies and adapted to generate said motion command signal based on a location of said x-ray detector in said plurality of first positions to maintain a predetermined spatial relationship between the x-ray source and the x-ray detector.

17. A diagnostic imaging apparatus comprising:

an x-ray source adapted to transmit an x-ray beam through an examination region;

an x-ray detector adapted to receive the x-ray beam and generate electric signals indicative of an intensity of the received x-ray beam;

a first mechanical arm assembly adapted to carry the x-ray detector, the first mechanical arm assembly being manually movable to hold the x-ray detector in a plurality of first positions relative to the examination region, the first mechanical arm assembly being adapted to generate a position feedback signal indicative of a first position of the x-ray detector relative to the examination region;

a second mechanical arm assembly adapted to carry the x-ray source, the second mechanical arm assembly being responsive to a motion command signal to selectively position the x-ray source at a plurality of second locations relative to the examination region; and

,

a control unit operatively associated with the first and second mechanical arm assembly and adapted to generate said motion command signal based on a location of said x-ray detector in said plurality of first positions, the control unit being adapted to receive said position feedback signal and generate said motion command signal to move the x-ray source to a second position relative to a position of the x-ray detector.

18. The diagnostic imaging apparatus according to claim 17 wherein the control unit is adapted to generate said motion command signal to maintain a predetermined spacial relationship between the x-ray source and the x-ray detector.

19. The diagnostic imaging apparatus according to claim 18 wherein the second mechanical arm assembly is adapted to carry the x-ray source on a first end and includes a second end carried on a support adapted to enable linear motion of the second mechanical arm assembly relative to the examination region.

20. In a radiographic imaging apparatus of the type including an x-ray source transmitting an x-ray beam along a path through an examination region and an x-ray detector receiving the x-ray beam and generating electric signals indicative of an intensity of the received x-ray beam, a method of positioning the x-ray source and the x-ray detector relative to the examination region comprising the steps of:

using a first positioning system operatively associated with the x-ray source, positioning the x-ray source in a range of first orientations relative to the examination region in response to a first command signal;

using a second positioning system operatively associated with the x-ray detector, positioning the x-ray detector in a range of second orientations relative to the examination region and generating an x-ray detector orientation feedback signal representative of the relative orientation between the x-ray detector and said examination region; and

,

using a control unit, generating said first command signal used by the first positioning system to control the path of the x-ray beam transmitted through the examination region based on said x-ray detector feedback orientation signal to maintain a predetermined spatial relationship between the x-ray emitter and the x-ray detector for each of said ranges of first and second orientations relative to the examination region.

21. The method according to claim 20 further comprising the steps of:

manually moving the second positioning system by a human operator to selectively position the x-ray detector in a range of third orientations relative to the examination region; and

,

using said control unit, generating said first command signal used by the first positioning system to control the path of the x-ray beam transmitted through the examination region based on said x-ray detector feedback orientation signal to maintain said predetermined spatial relationship between the x-ray emitter and the x-ray detector for said range of third orientations of the x-ray detector relative to the examination region.

22. A diagnostic imaging method comprising:

transmitting an x-ray beam generated by an x-ray source through an examination region;

receiving the x-ray beam at an x-ray detector and generating electric signals indicative of an intensity of the received x-ray beam;

manually moving a first mechanical arm assembly carrying the x-ray detector to hold the x-ray detector in a first position relative to the examination region;

generating a position feedback signal indicative of said first position of the x-ray detector relative to the examination region;

using a second mechanical arm assembly carrying the x-ray source, selectively positioning the x-ray source at locations relative to the examination region in response to a motion command signal; and

,

in a control unit operatively associated with the first and second mechanical arm assemblies, receiving said position feedback signal indicative of said x-ray detector in said first position and generating said motion command signal to move the x-ray source to a second position relative to a position of the x-ray detector.

23. The method according to claim 22 wherein the step of generating said motion command signal includes generating said motion command signal to maintain a predetermined spacial relationship between the x-ray source and the x-ray detector.

24. The according to claim 23 wherein the step of selectively positioning the x-ray source at locations relative to the examination region in response to said motion command signal includes moving the second mechanical arm assembly along a linear path relative to the examination region.