Portal de Periódicos da CAPES

The Use of a Linear Accelerator “Simulator” in Radiotherapy

1964; Wiley; Volume: 37; Issue: 437 Linguagem: Inglês

10.1259/0007-1285-37-437-394

1748-880X

D. Greene, Keith A. Nelson, Robert Gibb,

Lung Cancer Diagnosis and Treatment

In this hospital it is the usual practice, when tumour localisation procedures have been completed, for the initial “set up” of a radiotherapy treatment to be done by the radiotherapist. This may involve either the final inspection and fitting of the patient's mould, or the application of skin marks to specify the fields to be applied. Such marks may include the placing of the skin point of reference for a pin-and-arc treatment, or the field outline (including the outline of any organ to be shielded) in a regional treatment. In a large field treatment it may also be necessary to make a decision about the SSD to be used, while for pin-and-arc treatment on an isocentrically mounted machine it will be necessary to measure the SSD and the mean angle of incidence for each field. When each field of a treatment has been set up it is useful to be able to take a radiograph with the therapy beam as a final check on its accuracy. In so far as the ultimate success of the treatment depends on these processes, it is important that they should not be rushed, and with high output machines such as linear accelerators and large 60Co units, “marking out” may take as much time as several routine treatments. The treatment programme of the machine may be held up for a considerable time because of some technical difficulty in a particular set-up, while the arrival of the radiotherapist for an arranged appointment may be delayed.