In radiotherapy, linear accelerators are used to treat patients first of all suffering from cancer. The isocentre (intersection of the gantry and collimator rotation axes) is an important reference point. The room lasers which are used to position the patient, should intersect in the isocentre. The isocentre should be stable in space. This is especially valid when high conformal irradiation has to be applied to the patient.
isoPath is a scientific measurement tool suitable to measure the isocentre position relative to the room lasers and the isocentre path shape of a linear accelerator. The measurement results includes information about the isocentre position relative to the room lasers and the extent and shape of the isocentre path.
The measurement accuracy of the isocentre is in the range of 0.002 to 0.003 mm, the isocentre path points are measured with an accuracy of about 0.02 mm. The integral measurement time is about five minutes, when the gantry rotation axis is tested.