Multileaf collimators with transverse motion

Patent metadata

Field	Value
Publication number	US-9324468-B2
Application number	US-86137310-A
Country	US
Kind code	B2
Filing date	Aug 23, 2010
Priority date	Aug 23, 2010
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

A collimation assembly includes a multileaf collimator and motion assembly. The multileaf collimator includes a support body and a plurality of pairs of beam blocking leaves supported by the support body. The beam blocking leaves are longitudinally movable in a first direction. The motion assembly includes an actuator and a guide assembly operable to move the support body and thereby allowing the plurality of pairs of beam blocking leaves to move in a second direction generally transverse to the first direction.

First claim

What is claimed is:

1. A collimation assembly for selectively blocking radiation beams having a beam axis comprising a multileaf collimator and a motion assembly, wherein
the multileaf collimator comprises a support body and a plurality of pairs of beam blocking leaves supported by the support body, leaves of each pair being longitudinally movable in a first direction; and
the motion assembly comprises an actuator and a guide assembly operable to move the support body thereby allowing the plurality of pairs of beam blocking leaves to move in a second direction generally transverse to the first direction and the beam axis.

2. The collimation assembly of claim 1 wherein the plurality of pairs of leaves are arranged to substantially focus on a source, and the motion assembly is operable to move the support body thereby allowing the plurality of pairs of leaves to move in the second direction substantially in an arc trajectory substantially centered on the source.

3. The collimation assembly of claim 1 wherein the collimation assembly is movable generally transverse to the beam axis.

4. The collimation assembly of claim 1 further comprising a second motion assembly operable to move the support body thereby allowing the plurality of pairs of leaves to move in a third direction generally parallel to the first direction.

5. The collimation assembly of claim 4 wherein the second motion assembly is operable to allow the plurality of pairs of leaves to move in an arc trajectory substantially centered on a source.

6. The collimation assembly of claim 1 wherein the support body comprises one or more movable carriages operable to move the plurality of leaves in a third direction substantially parallel to the first direction.

7. A radiation apparatus comprising a radiation source operable to generate a beam having a beam axis and a collimation assembly operable to selectively block the beam, said collimation assembly comprises a multileaf collimator and a motion assembly, wherein
the multileaf collimator comprises a support body and a plurality of pairs of beam blocking leaves supported by the support body, leaves of each pair being longitudinally movable relative each other; and
the motion assembly comprises an actuator and a guide assembly operable to move the support body relative to the radiation source thereby allowing the beam blocking leaves to rotate about an axis that is angled relative to the beam axis.

8. The radiation apparatus of claim 7 wherein the plurality of pairs of leaves are longitudinally movable in a first direction, and the motion assembly is operable to move the support body in a second direction generally transverse to the first direction.

9. The radiation apparatus of claim 7 wherein the plurality of pairs of leaves are longitudinally movable in a first direction, and the motion assembly is operable to move the support body in a second direction generally parallel to the first direction.

10. The radiation apparatus of claim 7 wherein the plurality of pairs of leaves are longitudinally movable in a first direction, and the motion assembly is operable to move the support body in a direction generally transverse to the first direction and in a direction generally parallel to the first direction.

11. The radiation apparatus of claim 7 wherein the motion assembly is operable to rotate the support body about the axis that is substantially through the source and substantially perpendicular to the beam axis.

12. A radiation apparatus comprising:
a radiation source operable to generate a beam having an axis;
a collimation assembly operable to selectively block the beam, said collimation assembly comprising a multileaf collimator which comprises a support body and a plurality of pairs of beam blocking leaves supported by the support body, leaves of each pair being longitudinally movable relative each other;
a bearing assembly supporting the collimation assembly; and
a motion assembly operable to move the bearing assembly relative to the radiation source thereby allowing the collimation assembly to rotate about an axis that is angled relative to the beam axis.

13. The radiation apparatus of claim 12 wherein the motion assembly is operable to rotate the bearing assembly in two or more degrees of freedom thereby allowing the collimation assembly to rotate in two or more degrees of freedom.

14. A radiation apparatus comprising a radiation source and a collimation assembly which comprises a multileaf collimator and a motion assembly, wherein
the multileaf collimator comprises a support body and a plurality of pairs of beam blocking leaves supported by the support body, leaves of each pair being longitudinally movable relative each other in a first direction; and
the motion assembly comprises an actuator and a guide assembly operable to move the support body relative to the radiation source thereby allowing the beam blocking leaves to move in a second direction substantially in an arc that is centered substantially at the radiation source.

15. The radiation apparatus of claim 14 wherein the motion assembly comprises a four bar linkage mechanism where one bar comprises the support body.

16. The radiation apparatus of claim 14 wherein the motion assembly comprises an eight-axis mechanism connected to the support body, wherein the eight axes are substantially focused on the source and the motion of the support body is substantially on the surface of a sphere that is centered substantially at the source.

17. The radiation apparatus of claim 14 wherein the motion assembly comprises a four-axis mechanism connected to the support body, wherein the four axes are substantially focused on the source and the motion of the support body is substantially on the surface of a sphere that is centered substantially at the source.

18. A radiation apparatus comprising a radiation source and a collimation assembly, said collimation assembly comprises:
the multileaf collimator comprises a support body and a plurality of pairs of beam blocking leaves supported by the support body in two or more levels in a beam direction, leaves of each pair being longitudinally movable relative each other;
a first motion assembly operable to move the support body in a first direction; and
a second motion assembly operable to move the support body in a second direction different from the first direction.

19. The radiation apparatus of claim 18 wherein said second motion assembly comprises a four bar linkage mechanism where one bar comprises the support body.

20. A radiation method comprising:
providing a radiation beam from a source to a target in a subject;
defining a treatment field substantially conforming to the shape of the target using a multileaf collimator assembly comprising a support body and a plurality of beam blocking leaves supported by the support body, the plurality of beam blocking leaves being movable in a first direction, the treatment field being defined at least by positioning the plurality of beam blocking leaves relative to the beam; and
moving the defined treatment field in response to a motion of the target by moving the support body relative to the source in a second direction that is different from the first direction of the beam blocking leaves.

21. The radiation method of claim 20 wherein the defining step comprises moving at least a portion of the plurality of leaves longitudinally in the first direction, and the moving step comprises moving the support body in the second direction general

Assignees

• Mansfield Stanley
• Prince Steven W
• Varian Med Sys Inc

Inventors

• Mansfield Stanley
• Prince Steven W

Classifications

• A61N5/1045

  using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT · CPC title

• G21K1/046 Primary

  varying the contour of the field, e.g. multileaf collimators · CPC title