Test procedures for verification of an electron pencil beam algorithm implemented for treatment planning

Dosimeter Gel and MR Imaging for Verification of Calculated Dose Distributions in Clinical Radiation Therapy

“…The deviations were mainly found in the build-up region. For small electron fields, the complex scattering process from the electron applicator is underestimated using this dose planning system in the penumbra region (33). The deviations found were in accordance with the results in the present study and indicate an uncertainty in the calculated dose near the surface of the phantom and in the abutment region.…”

“…The performance of the specific treatment planning system used in this study have recently been tested for single photon and electron beams (32,33). Using a similar photon beam as in this study, only small differences were found when calculated depth dose curves and dose profiles were compared with diode measurements (32).…”

“…The deviations found were in accordance with the results in the present study and indicate an uncertainty in the calculated dose near the surface of the phantom and in the abutment region. The difference could be of significant importance using a matching technique like in the breast cancer treatment reported here (33). To achieve reliable matching techniques, treatment heads with a small amount of electron scatter are preferable and correctly simulated in the dose planning system (34).…”

Verification of Single Beam Treatment Planning Using a Ferrous Dosimeter Gel and MRI (FeMRI)

“…2b), differences of up to 5% were found, and the corresponding penumbra widths also differed significantly, 3.7 mm ( Table 2). Similar deviations have also been reported elsewhere (14) and can be explained by the way the TPS handles the lateral scatter of the electrons outside the primary beam. However, these discrepancies (best seen in Fig.…”

Can Photon IMRT be improved by combination with mixed electron and photon techniques?

“…The electron algorithm of TMS is based on Monte Carlo pre-calculated pencil beams (23,24). Good agreement between these calculations and measurements has been shown in cases relevant to this work (25). For photons, the pencil-beam dose calculation algorithm was used.…”