title: A note on designing tissue compensators for parallel opposed fields.
abstract: Missing tissue compensators are typically made to correct for the tissue defect separately for each of two parallel opposed radiation fields. Arguments and experimental evidence are provided to show that a more uniform dose distribution is achieved throughout the irradiated volume if the compensator is designed so that each opposed field delivers an equal dose to a surface defining midmass between the opposed body surfaces. An expedient method to approximate this result is to simply divide equally between the two parallel opposed fields the total amount of compensation otherwise required.
mesh_terms: D004867:Equipment Design; D006801:Humans; D009369:Neoplasms / Q000532:radiotherapy*; D010347:Patient Care Planning / Q000379:methods*; D011878:Radiotherapy / Q000295:instrumentation*; D011879:Radiotherapy Dosage