US 5,757,881 A · Redundant field-defining arrays for a radiation system

Abstract

A system for applying radiation therapy includes a radiation source for emitting a radiation beam and includes redundant treatment field-defining arrays for shaping the radiation beam. The radiation beam is initially shaped by a multileaf collimator having a side-by-side arrangement of leaf pairs. The leaves are individually manipulable to define apertures between the leaves of a pair. Thus, the contour of an irregular treatment field can be precisely defined. The second field-defining array includes field-defining members that are individually connected to corresponding leaves of the multileaf collimator. Preferably, the connections are mechanical linkages and there is a one-to-one correspondence of the field-defining members and the leaves. Adjustment of a leaf simultaneously adjusts a position of a corresponding field-defining member. Also in the preferred embodiment, the second array is contained within a conically shaped housing that provides beam guidance. As a result of the shape of the housing and the redundant arrays, healthy tissue is shielded during irradiation of a patient.

Claims16

Dependent claims

A system for applying radiation therapy comprising:

a radiation source for emitting a radiation beam;
a multileaf collimator having a first shaping means for defining a contour of a treatment field, said first shaping means having a plurality of leaves, including a first set of side-by-side leaves which are individually manipulable to extend toward and away from a second set of individually manipulable side-by-side leaves;
a second shaping means for defining said contour of said treatment beam, said second shaping means being on a side of said multileaf collimator opposite to said radiation source, said second shaping means having a third set of field-defining members that are individually connected to corresponding leaves of said first set, said second shaping means having a fourth set of field-defining members that are individually connected to corresponding leaves of said second set;
and
means for adjusting said leaves of said first and second sets to vary said contour of said treatment field, wherein adjusting a position of a leaf simultaneously adjusts a position of a field-defining member connected to said leaf.

2 more elements

A system for applying radiation therapy comprising:

a radiation source for directing a radiation beam along a beam path;
a contour collimator positioned along said beam path, said collimator having first and second arrays of closely proximate coarse field-defining members, each coarse field-defining member of said first array being operatively associated with a coarse field-defining member of said second array, said operatively associated coarse field-defining members being displaceable to selectively vary a first beam passageway therebetween;
an applicator connected to said contour collimator along said beam path, said applicator having third and fourth arrays of closely proximate fine field-defining members, each fine field-defining member of said third array being operatively associated with a fine field-defining member of said fourth array, said operatively associated fine field-defining members being displaceable to selectively vary a second beam passageway therebetween, said fine field-defining members being movable in a direction generally coincident with movement of said coarse field-defining members;
and
mechanical linkage connecting each of said coarse field-defining members with one of said fine field-defining members to establish a one-to-one correspondence with respect to displacement of said coarse and fine field-defining members.

2 more elements

Dependencies are inferred from the claim text.

Redundant field-defining arrays for a radiation system

Life of this patent

Redundant field-defining arrays for a radiation system

Life of this patent

Abstract

Claims16