The Leeds Teaching Hospitals NHS Trust

Radiotherapy technology services

The Leeds Cancer Centre Radiotherapy Service has 12 treatment machines. Each machine is capable of treating 50 to 60 patients per day.  

 linac whole 

 

 The photograph above shows a picture of a Linac

Your course of radiotherapy is likely to be delivered on the same treatment machine daily. You may be treated on a different machine if an equipment breakdown occurs or when routine equipment maintenance is needed. When this happens, Clinical Technologists and Scientists jointly provide the engineering and physics skills to confidently make sure that the treatment machine is safe to return to clinical use.                                                                                                         

The treatment room is split into a clinical area and an engineering area by a dividing screen. The whole treatment machine is large and weighs several tons.

linac back

 

Most of the machine is behind the screen. The gantry is held in position by the base platform and rotates upon it. The arm and head are connected to the gantry and rotate with it. Together with the couch, the machine can be positioned to suit all treatments.

This photograph shows what is behind the wall.

 

 

 

 

 

From an engineering point of view, treatment accuracy is dependent on radiation strength and shape, machine position, couch position and patient imaging systems. The machines computer based control system, reads data from many two channel sensors on these critical systems. 

Permanent faults can be traced and quickly repaired. Intermittent faults are difficult to reproduce and time consuming to find.Parts prone to wear and tear are replaced during routine maintenance, to reduce the chance of failure during clinical use. All major and surprisingly some minor machine changes can require lengthy testing. We need to prove that the machine can position itself accurately, deliver radiation correctly and produce clear images. 

Treatment machines need routine upgrades to allow delivery of more complex treatments. Radiographers carry out extra clinical testing to prove these treatments can be delivered safely.