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The Treatment Apparatus:

     The equipment used to generate and deliver X-ray radiotherapy is called a Linear Accelerator  ( LA or LinAc). Everything about these machines is impressive including the name, appearance, and price tag. 

The gantry houses the X-ray beam source and can be rotated to any angle in the vertical plane (right picture). This ability, in combination with the various possible table positions, means that the X-ray beam can be directed to any area on the patient with great accuracy and consistency. Laser devices attached to the walls and ceiling are used by the radiographers to position the patient on the table prior to therapy. The room housing the LA is built of lead enhanced concrete with an entrance corridor which turns through two right angles to prevent radiation leakage ( X-rays can't go round corners). A control and monitoring station is obviously safely outside the bunker, and the radiographers have CCTV to view the patient inside and can respond quickly to any distress.

   I had attended one of the guided tours of the therapy suites offered to patients prior to treatment and found it very helpful. It was reassuring to know, for instance, that the machines were checked at least daily to ensure correct calibration and operation. Mount Vernon cancer treatment centre currently has at least ten Linear Accelerators installed.