Clinical application of an electronic imaging device for assisting patient set-up in radiotherapy

As radiotherapy treatment set-ups are becoming more complicated and a greater emphasis is placed on accuracy, there is an increasing need to verify and record the actual treatments being given. A direct electronic imaging device is currently marketed by Varian (the DYNARAY ID), which uses the latest technology in detection and image processing to obtain digital images of the patient's anatomy using the actual treatment beam. At Norwich we have been using a prototype machine in a busy district radiotherapy centre and have examined over 50 patients. We have found the images easy to obtain and the technique superior to the standard practice of using verification radiographs. The role of this device lies in aiding quality assurance of treatments whilst generating a permanent record of the actual treatment given.