Patient-specific intensity modulated radiotherapy quality assurance using an electronic portal imaging device

Main Article Content

Eduardo F. Larrinaga Cortina
David N. Alonso Fernández

Abstract

modern clinical electron linear accelerator was commissioned at the Department of Radiotherapy in the Oncology and Radiobiology Institute. The use of electronic portal image device (EPID) for patient-specific intensity modulated radiotherapy (IMRT) quality assurance is assessed and validated. An IMRT step & shoot approach, using multileaf collimator was used. The EPID dose-response curve was determined for a 6MV photon beam. The EPID effective water scattering depth () was assessed through measurements of its response versus field size variation and compared with the output factor scatter at different depths, calculated with a radiotherapy treatment planning system (TPS).
Dose profiles and dose maps were calculated at with the TPS, using a collapsed beam setup. The dose maps and profiles were compared with the processed EPID images for simple cases (i.e. open and wedged fields) and a more complex case (a head and neck IMRT clinical case).
Comparison was performed using the Gamma function. Results showed Gamma passing rates higher than 90% for all compared points, using comparison criteria of dose difference 3% and 4mm of distance to agreement.

Article Details

How to Cite
Larrinaga Cortina, E. F., & Alonso Fernández, D. N. (1). Patient-specific intensity modulated radiotherapy quality assurance using an electronic portal imaging device. Nucleus, (59). Retrieved from http://nucleus.cubaenergia.cu/index.php/nucleus/article/view/620
Section
Ciencias Nucleares

References

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