Purpose: To introduce a practical method of using an Electron Density Phantom (EDP) to evaluate different dose calculation algorithms for photon beams in a treatment planning system (TPS) and to commission the Anisotropic Analytical Algorithm (AAA) with inhomogeneity correction in Varian Eclipse TPS. Methods and Materials: The same EDP with various tissue-equivalent plugs (water, lung exhale, lung inhale, liver, breast, muscle, adipose, dense bone, trabecular bone) used to calibrate the computed tomography (CT) simulator was adopted to evaluate different dose calculation algorithms in a TPS by measuring the actual dose delivered to the EDP. The treatment plans with a 6-Megavolt (MV) single field of 20 × 20, 10 × 10, and 4 × 4 cm 2 field sizes were created based on the CT images of the EDP. A dose of 200 cGy was prescribed to the exhale-lung insert. Dose calculations were performed with AAA with inhomogeneity correction, Pencil Beam Convolution (PBC), and AAA without inhomogeneity correction. The plans were delivered and the actual doses were measured using radiation dosimetry devices MapCheck, EDR2-film, and ionization chamber respectively. Measured doses were compared with the calculated doses from the treatment plans. Results: The calculated dose using the AAA with inhomogeneity correction was most consistent with the measured dose. The dose discrepancy for all types of tissues covered by beam fields is at the level of 2%. The effect of AAA inhomogeneity correction for lung tissues is over 14%. Conclusions: The use of EDP and Map Check to evaluate and commission the dose calculation algorithms in a TPS is practical. In Varian Eclipse TPS, the AAA with inhomogeneity correction should be used for treatment planning especially when lung tissues are involved in a small radiation field.

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The electromagnetic form factors of deuteron are investigated on hybrid quarkhadron model, where meson exchange and six-quark clusters are taken into account. It is found that pion-recoil current and six-quark clusters have important effects on charge form factor, magnetic structure function and tensor polarization, which are all sensitive to the interaction between nucleons. The theoretical predictions agree well with new experimental data.

SRS vs 47% with WBRT (p Z 0.02); however, a small number of patients experienced 1SD decline in 3 or more CM and these results were more variable across the time points. SRS had a lower observed proportion of patients with a 2 SD decline in 1 or more CM at every time point and these differences were found to be significant at 3 and 9 months. Similar results were observed for better SRS outcomes given a 2 SD decline at 2 or more and 3 or more CM, although statistical significance was lacking. QOL scores had mixed results. WBRToften had lower estimated mean QOL at three months compared to SRS, but this difference crossed to SRS having lower estimated mean QOL at 24 months for physical well-being (WB)WB, emotional WB, functional WB, FACT-G, BR, and FACT-BR (p<0.05 for difference in slope of each measure). A 2 SD decline in cognition was estimated to decrease mean FWB by 6.4 units (95% CI:-11,-1.75; p Z 0.007) and decrease mean overall quality of life by 5.1 units (95% CI:-7.7,-2.5; p<0.001). Conclusion: We report the first pooled prospective study demonstrating the long-term outcomes of patients with brain metastases after cranial radiation. WBRT was associated with worse cognitive outcomes. Impaired cognition is associated with worse QOL.

We study the effects of six-quark cluster and meson exchange current on quasielastic electron-deuteron scattering, using the hybrid quark-hadron model incorporating the contribution of the isoscalar meson exchange current. Our results indicate that the final state interaction, isoscalar and isovector meson exchange currents, and six-quark cluster contribute few to the quasielastic peak. However, they affect the extracted neutron electromagnetic form factors to some extent.