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Wedged beams have often been used in clinical photon radiotherapy to compensate missing tissues and dose gradients. In this work, we designed a wedge filter made of wax to be implemented in electron beam radiotherapy. Measurements were carried out for hexahedral high-energy electron beams (5-14 MeV) generated by Siemens Mevatron linear accelerator by using radiographic film dosimetry for off-axis dose profiles and depth doses' measurements. This study showed that there was a large difference between open and wedged PDD, and this difference was decreased with the electron-beam energy increase. Therefore, we recommend using wax wedge filters with higher electron energies, and take into account the increase in the surface dose and the decrease of the depth of maximum dose when used with low electron energies

Wedged beams have often been used in clinical photon radiotherapy to compensate missing tissues and dose gradients. In this work, we designed a wedge filter made of wax to be implemented in electron beam radiotherapy. Measurements were carried out for hexahedral high-energy electron beams (5-14 MeV) generated by Siemens Mevatron linear accelerator by using radiographic film dosimetry for off-axis dose profiles and depth doses' measurements. This study showed that there was a large difference between open and wedged PDD, and this difference was decreased with the electron-beam energy increase. Therefore, we recommend using wax wedge filters with higher electron energies, and take into account the increase in the surface dose and the decrease of the depth of maximum dose when used with low electron energies

Wedged beams have often been used in clinical photon radiotherapy to compensate missing tissues and dose gradients. In this work, we designed a wedge filter made of wax to be implemented in electron beam radiotherapy. Measurements were carried out for hexahedral high-energy electron beams (5-14 MeV) generated by Siemens Mevatron linear accelerator by using radiographic film dosimetry for off-axis dose profiles and depth doses' measurements. This study showed that there was a large difference between open and wedged PDD, and this difference was decreased with the electron-beam energy increase. Therefore, we recommend using wax wedge filters with higher electron energies, and take into account the increase in the surface dose and the decrease of the depth of maximum dose when used with low electron energies

Wedged beams have often been used in clinical photon radiotherapy to compensate missing tissues and dose gradients. In this work, we designed a wedge filter made of wax to be implemented in electron beam radiotherapy. Measurements were carried out for hexahedral high-energy electron beams (5-14 MeV) generated by Siemens Mevatron linear accelerator by using radiographic film dosimetry for off-axis dose profiles and depth doses' measurements. This study showed that there was a large difference between open and wedged PDD, and this difference was decreased with the electron-beam energy increase. Therefore, we recommend using wax wedge filters with higher electron energies, and take into account the increase in the surface dose and the decrease of the depth of maximum dose when used with low electron energies

Wedged beams have often been used in clinical photon radiotherapy to compensate missing tissues and dose gradients. In this work, we designed a wedge filter made of wax to be implemented in electron beam radiotherapy. Measurements were carried out for hexahedral high-energy electron beams (5-14 MeV) generated by Siemens Mevatron linear accelerator by using radiographic film dosimetry for off-axis dose profiles and depth doses' measurements. This study showed that there was a large difference between open and wedged PDD, and this difference was decreased with the electron-beam energy increase. Therefore, we recommend using wax wedge filters with higher electron energies, and take into account the increase in the surface dose and the decrease of the depth of maximum dose when used with low electron energies

Background: Comprehensive radiation therapy fields used in the management of early-stage breast cancer. Our aim to determine the variability of the depth of supraclavicular (SCV) & infraclavicular (ICV) nodes, to estimate the actual radiation dose received by these regions in a series of patients treated in the traditional technique, and to compare these doses with those received by using an optimized dosimetric technique. Methods: In 20 patients undergoing treatment-planning computed tomography (CT) scanning in the treatment position, the maximum depth of the SCV and ICV lymph nodes and brachial plexus were measured on CT images. Doses received at the 90% isodose surface for the SCV and ICV volumes were then estimated by using traditional dose calculations and optimized planning. A repeated measures analysis of covariance was used to compare the SCV and ICV depths and to compare the doses achieved with the traditional and optimized methods. Results: We found that SCV nodes> 3 cm and ICV nodes> 4.5 cm will not be covered by 90% isodose surface. However, as the depth to the SCV and ICV nodes increases, the percentage of the SCV volume encompassed within the 90% isodose surface significantly decreases for cases of therapy planned by using traditional planning versus the conformal optimized plan (p 0.05%)

Background: Comprehensive radiation therapy fields used in the management of early-stage breast cancer. Our aim to determine the variability of the depth of supraclavicular (SCV) & infraclavicular (ICV) nodes, to estimate the actual radiation dose received by these regions in a series of patients treated in the traditional technique, and to compare these doses with those received by using an optimized dosimetric technique. Methods: In 20 patients undergoing treatment-planning computed tomography (CT) scanning in the treatment position, the maximum depth of the SCV and ICV lymph nodes and brachial plexus were measured on CT images. Doses received at the 90% isodose surface for the SCV and ICV volumes were then estimated by using traditional dose calculations and optimized planning. A repeated measures analysis of covariance was used to compare the SCV and ICV depths and to compare the doses achieved with the traditional and optimized methods. Results: We found that SCV nodes> 3 cm and ICV nodes> 4.5 cm will not be covered by 90% isodose surface. However, as the depth to the SCV and ICV nodes increases, the percentage of the SCV volume encompassed within the 90% isodose surface significantly decreases for cases of therapy planned by using traditional planning versus the conformal optimized plan (p 0.05%)

The aim of this study was to compare open asymmetric field-in-field (FIF) to physical wedge for compensation of dose inhomogeneity in tangential whole breast irradiation. Patients and Methods: Ten consecutive patients had undergone breast conserving surgery followed by whole breast irradiation were considered. Two 3D treatment plans were generated for each patient using: physical wedge and FIF techniques. For both plans, the doses to 2% (D2) and 98% (D98) of the planning target volume (PTV), as well as PTV95%, PTV97-103%, and PTV>107% of the prescribed dose were used to evaluate the effect on dose homogeneity. The evaluation of organ at risk (OAR) carried out by comparing volumes received over 40% of dose (17Gy) in the ipsilateral lung, 80% of dose (34Gy) in the heart, and mean dose of contralateral lung. Also, the average total monitor units (MU) for both were compared. Results: The FIF technique was better than physical wedged technique in terms of D2, D98, PTV>107%. FIF technique achieved 8.1% dose improvement index compared to physical wedges technique and 34% reduction in the mean monitor units as it reported 470 MU and 310 MU for physical wedges and FIF technique respectively. The differences between the two techniques were insignificant regarding the OAR. FIF can save up to 219 seconds compared to tangential wedged field. Conclusion: Asymmetric FIF technique improves PTV conformity without compromising OAR. It also reduces treatment time and hence can replace physical wedge, especially in busy departments.