Objective:To design an integrated dose calibration phantom,so as to optimize the operation process under the premise of ensuring measurement accuracy of conventional dose calibration of accelerator.Methods:According to the size of the ionization chamber,a piece of plexiglass plate with the size of 20cm×20cm×7cm was processed into an integrated solid phantom.According to the recommended measurement method in the No.IAEA277 report of International Atomic Energy Agency(IAEA),the output of selected energy beam of the accelerator was calibrated by using a one-dimensional water tank so that 100MU corresponded to 100cGy at the maximum dose point on the central axis of the beam.And then,the dose calibration of the integrated solid phantom was carried out.The measurement results of the integrated solid phantom and the one-dimensional water at the selected energy beam output were compared to analyze the reliability of the integrated solid phantom calibration.Results:Within the variation range of the accelerator output from 60 to 140 MU,the relative errors measured using the integrated solid phantom and the one-dimensional water phantom for X6 rays were-0.15%,-0.13%,-0.10%,-0.03%,and-0.03%respectively,with the same magnitude and consistent direction.The values of the E12 rays are all 0.09%,-0.03,0.02%,0.03%,and-0.02%,with the same magnitude and consistent direction.Conclusion:The integrated solid phantom can conduct routine dose calibration of accelerators,which is more convenient in operation process.Its repeat precision of positioning is significantly improved.At the same time,it can reduce various errors caused by personnel operation,and provide a more reliable and efficient solution for dose calibration.

Objective:To design an integrated dose calibration phantom,so as to optimize the operation process under the premise of ensuring measurement accuracy of conventional dose calibration of accelerator.Methods:According to the size of the ionization chamber,a piece of plexiglass plate with the size of 20cm×20cm×7cm was processed into an integrated solid phantom.According to the recommended measurement method in the No.IAEA277 report of International Atomic Energy Agency(IAEA),the output of selected energy beam of the accelerator was calibrated by using a one-dimensional water tank so that 100MU corresponded to 100cGy at the maximum dose point on the central axis of the beam.And then,the dose calibration of the integrated solid phantom was carried out.The measurement results of the integrated solid phantom and the one-dimensional water at the selected energy beam output were compared to analyze the reliability of the integrated solid phantom calibration.Results:Within the variation range of the accelerator output from 60 to 140 MU,the relative errors measured using the integrated solid phantom and the one-dimensional water phantom for X6 rays were-0.15%,-0.13%,-0.10%,-0.03%,and-0.03%respectively,with the same magnitude and consistent direction.The values of the E12 rays are all 0.09%,-0.03,0.02%,0.03%,and-0.02%,with the same magnitude and consistent direction.Conclusion:The integrated solid phantom can conduct routine dose calibration of accelerators,which is more convenient in operation process.Its repeat precision of positioning is significantly improved.At the same time,it can reduce various errors caused by personnel operation,and provide a more reliable and efficient solution for dose calibration.

Objective:To compare the differences of lung function parameters of the patients with congenital scoliosis (CS)or idiopathic scoliosis (IS),and to clarify their influence in respiratory function.Methods:Sixty-one patients of scoliosis undergoing operation were selected.According to the cause they were divided into 25 patients with CS and 36 patients with IS.The changes of lung function parameters and the differences in the patients with scoliosis were analyzed. Results:The ages,body weights, Cobb angles of the patients in two groups had no significant differences.There were 6 cases and 12 cases of ventilation disturbance in CS and IS groups,and 15 cases and 25 cases of ventilation dysfunction.The levels of residual volume (RV),ratio of residual volume to total lung capacity (RV/TLC),RV/TLC percent predicted (RV/TLC% pred )in two groups were higher than the normal. The percentage of forced vital capacity predicted (FVC%pred)and FEV1/FVC in CS group were both lower than those in IS group (P<0.05).Some pulmonary function parameters such as vital capacity (VC%pred),FVC%pred,forced expiratory volume in one second (FEV1%pred), maximal mid expiratory flow (MMEF%pred), maximal voluntary ventilation (MVV%pred),TLC%pred and diffusion capacity for carbon monoxide of the lung (DLCO%pred)were negtively correlated with Cobb angle (r=-0.54--0.35,P<0.05)in IS group and the TLC%pred was negtively correlated with Cobb angle (r=-0.047,P<0.05)in CS group.Conclusion:Different types of scoliosis have influence in the pulmonary function of the patients.The degree of pulmonary function injury of the patients with IS is worse than that of the CS patients.The IS patients need treatment in time.