Abstract: A radiotherapy apparatus is disclosed, having an imaging system and a therapeutic radiation source, an imageable volume into which therapeutic radiation may be provided, a first imaging means for providing an image resulting from the imaging system and a second imaging means for providing an image resulting from the therapeutic radiation, and a patient support moveable relative to the volume, wherein the patient support is provided with a calibration portion comprising at least one object of a material capable of appearing in the image produced by the first imaging means and at least one object of a material capable of appearing in the image produced by the second imaging means, the at least one object being fixed in a pre-determined position relative to the calibration portion and the calibration portion being fixed in a pre-determined position relative to the patient support, the patient support being moveable so that the at least one object portion may optionally be positioned within or outside the volume.

Abstract: A radiotherapy apparatus is disclosed, having an imaging system and a therapeutic radiation source, an imageable volume into which therapeutic radiation may be provided, a first imaging means for providing an image resulting from the imaging system and a second imaging means for providing an image resulting from the therapeutic radiation, and a patient support moveable relative to the volume, wherein the patient support is provided with a calibration portion comprising at least one object of a material capable of appearing in the image produced by the first imaging means and at least one object of a material capable of appearing in the image produced by the second imaging means, the at least one object being fixed in a pre-determined position relative to the calibration portion and the calibration portion being fixed in a pre-determined position relative to the patient support, the patient support being moveable so that the at least one object portion may optionally be positioned within or outside the volume.

Abstract: A method of aligning the radiation beam in a radiotherapy system comprising a source for producing a beam of radiation and an imaging device for imaging from the beam, both mounted to be rotatable about an axis, a fiducial phantom between the source and imaging device, the method comprising: rotating the beam and imaging device in a trajectory about the axis while obtaining images of the fiducial phantom from a plurality of different angles, at least one image including a feature of the imaging apparatus, adjusting the trajectory of the source relative to that feature to position the isocenter substantially in the center of the volume, determining from each image of the fiducial phantom the position of the source at the rotational position the image was obtained, and calculating the center of rotation of the positions of the source to define the isocenter of the system.

Abstract: Embodiments of the present invention provide markers, phantoms, and associated methods of calibration which are suitable for use in both magnetic resonance imaging and radiographic imaging systems. A marker includes a first marker component having a first hydrogen proton density and a first mass density; and a second marker component having a second hydrogen proton density different than the first hydrogen proton density, and a second mass density different than the first mass density. The first marker component and the second marker component are non-magnetic.

Abstract: Embodiments of the present invention provide markers, phantoms, and associated methods of calibration which are suitable for use in both medical resonance imaging and radiographic imaging systems. A marker includes a first component having a first hydrogen proton density and a first mass density; and a second component having a second hydrogen proton density different than the first hydrogen proton density, and a second mass density different than the first mass density. The first and second components are non-magnetic.