Patent ID: 6275564
Filing Date: 2001-08-14
Classification: A61B,A61N

Abstract:
A positioner useful in stereotactic radiation treatment of a patient by radiation from a radiation source from which a radiation beam is emitted along a beam axis, the radiation source being housed in a housing attached to a gantry arm having a gantry rotational axis, the positioner comprising:a source adapter arm arranged to be attached to the radiation source such that the position of the source adapter arm is determined by the position of the radiation source, and the position of the source adapter arm relative to the radiation source is independent of the position of the gantry arm relative to the radiation source;a measurement assembly mounted on said source adapter arm for making measurements with respect to a measurement axis, said measurement axis initially substantially intersecting said beam axis, said measurement assembly measuring a misalignment of said measurement axis with said beam axis;a patient support frame having a frame axis; anda target assembly which comprises a bar slidingly attached to said patient support frame so that said bar is adjustable along any of three mutually perpendicular axes with respect to said frame, and wherein at least one marker extends from said bar, said marker being sensed by said measurement assembly and said marker being accurately positionable with respect to said beam axis, said measurement axis and said frame axis.