Field separation of adjoining therapy fields.
The question of optimal portal separation between two contiguous fields is of importance in radiotherapy. An analytical linear model based on experimental data has been developed for a Co-60 unit (Siemens Gammatron S 65 K). It allows the computation of the separation distance for any combination of field sizes not necessarily having the same source-surface-distance, defined either with penumbra trimmers or focused shaping blocks.
D003037:Cobalt Radioisotopes / Q000627:therapeutic use; D006801:Humans; D011867:Radioisotope Teletherapy / Q000379:methods; D011874:Radiometry / Q000379:methods*; D011878:Radiotherapy / Q000379:methods*; D011879:Radiotherapy Dosage
D003037:Cobalt Radioisotopes