Absorbed dose and transmission factor in blocked fields for radiotherapy treatments with 6 MV X-ray
Por:
Buenfil A.E., Rodríguez-González M.F., González G.R., Brandan M.E.
Publicada:
1 ene 2006
Resumen:
Absorbed dose and transmission factors were determined for 6 MV X-ray fields applied in four conventional external radiation treatments where protection blocks are used to shield organs at risk. Studied treatments are: head and neck (cancer of the larynx), breast (breast cancer), brain (brain tumours) and pelvis (cervix-uterine cancer). Experimental determinations were made using ionization chambers and thermoluminescent dosimeters, at different locations in phantoms, for blocked and unblocked fields. Calculated absorbed doses, using the treatment planning system and Clarkson method, were compared to those measured. Measured transmission factor values ranged from 5% to 18%. It was found that the planning treatment system may underestimate the absorbed dose under the blocks, up to 35%. © ESEO 2006.
Filiaciones:
Buenfil A.E.:
lnstituto de Fisica, UNAM, México D.F., Mexico
Rodríguez-González M.F.:
lnstituto de Fisica, UNAM, México D.F., Mexico
Hospital San Juan de Dios, Sail José, Costa Rica
González G.R.:
Instituto Nacional de Cancerologia, Tlalpan, México D.F., Mexico
Hospital Angeles de Las Lomas, México D.F., Mexico
Brandan M.E.:
lnstituto de Fisica, UNAM, México D.F., Mexico
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