| 摘要 |
An apparatus comprising a radiotherapy delivery apparatus which itself comprises a radiation source with a limited range of rotation about at least one axis, plus an imaging device and a control means. The apparatus further comprises a treatment planning computer that accepts an image of a patient. The source is capable of rotation in that axis through a range of at least x degrees and a parameter is passed to the treatment planning computer defining the sources available range as x-e where e>0 and the control means detects the patient position using the imaging device determining a rotation r of the patient around the axis relative to the image used by the treatment planning computer and if r<e will compensate for the rotation by offsetting the source by a rotation equal to r. The patient image may be a CT scan, possibly obtained via the imaging device. The source and imaging device may be integrated and possibly mounted on a rotatable gantry. Preferably the control means determines the rotation r by obtaining a further image of the patient which may be a CT scan and where the rotation r may be determined by comparing the image and the further image. |
