TY - JOUR
TI - MLC positional accuracy evaluation through the Picket Fence test on EBT2 films and a 3D volumetric phantom
AU - Antypas, C.
AU - Floros, I.
AU - Rouchota, M.
AU - Armpilia, C.
AU - Lyra, M.
JO - Journal of Applied Clinical Medical Physics
PY - 2015
VL - 16
TODO - 2
SP - 189-197
PB - Journal of Applied Clinical Medical Physics
SN - 1526-9914
TODO - 10.1120/jacmp.v16i2.5185
TODO - computer program;  devices;  evaluation study;  film dosimeter;  human;  imaging phantom;  intensity modulated radiation therapy;  magnetic and electromagnetic equipment;  patient positioning;  radiotherapy;  radiotherapy dosage;  radiotherapy planning system;  standards, Film Dosimetry;  Humans;  Particle Accelerators;  Patient Positioning;  Phantoms, Imaging;  Radiotherapy Dosage;  Radiotherapy Planning, Computer-Assisted;  Radiotherapy Setup Errors;  Radiotherapy, Intensity-Modulated;  Software
TODO - The accuracy of MLC positions during radiotherapy is important as even small positional deviations can translate into considerable dose delivery errors. This becomes crucial when radiosensitive organs are located near the treated volume and especially during IMRT, where dose gradients are steep. A test commonly conducted to measure the positional accuracy of the MLCs is the Picket Fence test. In this study two alterations of the Picket Fence test were performed and evaluated, the first one using radiochromic EBT2 films and the second one the Delta4PT diode array phantom and its software. Our results showed that EBT2 films provide a relatively fast, qualitative visual inspection of the significant leaf dispositions. When slight inaccuracies need to be revealed or precise numerical results for each leaf position are needed, Delta4PT provides the desired accuracy of 1 mm. In treatment modalities where a higher accuracy is required in the delivered dose distribution, such as in IMRT, precise numerical values of the measurements for the MLC positional inspection are required.
ER -