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@#<b>Objective</b> To study the feasibility of clinical application of an individualized customized material. <b>Methods</b> Five batches of individualized customized materials were randomly selected, from which 10 cm × 11 cm samples were intercepted for experimental analysis. Among them, 10 cm × 10 cm materials were selected to perform dosimetric analysis and HU change analysis before and after irradiation with a radiotherapy dose for breast cancer of 50 Gy as the irradiation basis. The center Point 1 on the lower surface of the individualized material and the center Point 2 of the solid water volume were selected for dosimetric analysis before and after the sample is irradiated. After reaching a sufficient amount of irradiation, the 1 cm × 10 cm materials intercepted in the center position and the remaining 1 cm × 10 cm materials after the first sampling were sent to the material science laboratory for analysis of physical properties of density, viscosity, hardness, and tear strength. <b>Results</b> In the comparative analysis of HU values before and after exposure, after receiving 50 Gy dose irradiation, the difference rate of HU value was 5.252%, which was close to the expected 5% difference rate in clinical medicine. In the dosimetric analysis of Point 1 and Point 2, the dose in the irradiated samples was significantly higher than that in the unirradiated samples; the dose in Point 1 increased by 3.742%, and the dose in Point 2 increased by 2.039%. Before and after irradiation, except for the physical density which showed a significant difference, there was no significant difference in viscosity, hardness, and tear strength. <b>Conclusion</b> The individualized customized material can meet the requirements of routine clinical medicine.
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Objective To study the dosimetry effect of Dw and Dm middle and lower esophageal cancer in Monaco treatment planning system (TPS). Methods 30 patients with T3N0M0StageⅡa middle and lower esophageal cancer were selected for experiment. For each patient, optimize the plan using dose to water (Dw) and dose to medium (Dm) dose calculation mode, then rescale prescription dose to 95% volume of PTV. Compare the difference in the two mode, conformity index (CI), Homogeneity index (HI), Mean dose (Dmean), Minimum dose (Dmin), Maximum dose (D2), Dose to Organ at risk (OAR), MU, Optimization time, photon usage, and QA results of MatriXX and Arc Check. Use SPSS for multivariate analysis. Results In the dose evaluation of the middle and lower esophageal cancer cases under different dose calculation methods, the spinal cord, trachea, V20 of the whole lung, and D2 of the liver have significant dosimetric differences, the dose value, the sequential dose results were compared as (37.92 ± 1.11)/(35.85 ± 1.08), (59.91 ± 1.43)/(60.25 ± 0.98), (22.52 ± 1.75)/(21.38 ± 2.01), (42.89 ± 0.52)/(41.73 ± 0.58). In the comparison of dose cloud distribution, the difference is mainly located in the cavity and the inner wall of the lung in the target area, the dose in the target cavity in the Dw group is higher than that in the Dm group. The dose in the inner and outer walls of the lung cavity in the Dw group are slightly adducted than that in the Dm group, especially in the central area.Dose QA of MartiXX (3%-3 mm) and Arc Check (2%-2 mm) with different dose calculation methods of 60 plans of 30 cases have all passed clinical requirements. Dm Group is better than Dw group. Conclusion It is recommended to use Dm dose calculation method for Monaco 5.11 TPS in the condition of treatment planning for middle and lower esophageal cancer.
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Objective To investigate the effect of cotton pad plus compression bandage on radiation doses from radiation therapy of keloid dermoplasty.Methods Radiation doses from electron beams with different energies were measured using Siemens Primus-H accelerator,PTW-Quickcheck and 1-10 layers of dry,wet,blood cotton pad,respectively.Results The cotton pad could be used to prevent errhysis after radiation therapy of keloids.When 5 or more layers of cotton pad,about 2 cm,were used and errhysis still occur red,9 MeV electron beam should be used for the purpose of achieving the desirable dose and treatment result without occurrence of errhysis.Conclusions In clinical practice,to achieve the desirable dose for keloid treatment,electron beam energy should be adapted according to the errhysis situation.It is recommended to provide the measured data to determine the prescribed dose.
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Objective To establish a novel Monte Carlo simulation method for reconstruction of medical accelerator model and X?ray energy spectrum based on IAEA Varian 6 MV X?ray phase?space file and photon energy spectrum of the target accelerator. Methods The verified 6 MV X?ray phase?space files were preprocessed to elevate the energy of each particle. Particles were saved in different Phase?Space?Let ( PSL) files according to their position and energy, yielding an initial photon energy spectrum for Monte Carlo simulation of accelerator under an initial target energy. The initial photon energy spectrum was fit to a photon energy spectrum of an accelerator ( Elekta Precise 10 MV X?ray accelerator) under an unknown target energy to yield a fitting coefficient, which was the weight of each PSL. Finally, an accelerator model under an unknown target energy was reconstructed using the initial PSL files and the weight information. The percentage depth dose ( PDD) distribution was calculated in different square open fields. The effectiveness of this method was verified using one dimensional gamma passing rate. Results The peak position and overall distribution of the reconstructed 10 MV photon energy spectrum were in accordance with those of the verified 10 MV photon energy spectrum. The PDD calculated from the reconstructed 10 MV accelerator model agreed well with the measured PDD. The one?dimensional gamma passing rate was above 96%( 1%/1 mm, threshold=0%) . Conclusion The Monte Carlo reconstruction method proposed in this study is reliable, accurate, and effective.
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Objective To explore the multi-modal MRI characteristics of breast cancers in dense breasts.Methods 120 patients with breast cancer shown on mammography underwent breast MRI,which were solitary and confirmed by pathological examination. According to the BI-RADS classification of breast,the 120 cases were divided into two groups including dense type breast and non-dense type one.The differences in morphological features,ADC values (b=1 000 s/mm2 )and time-signal intensity curve (TIC)of the lesions between two groups were analyzed and compared.Statistical analysis was performed using SPSS1 6.0.Results The breast cancers in dense breast were vulnerable to have a spiculated margin (44/68 in the dense breast group vs.1 6/52 in the non-dense breast group,P =0.000).The size of the lesion in dense breast (1.83 ±0.98)cm was bigger than that in non-dense breast (1.40±0.46)cm (P =0.005).The non-mass-like enhancement of the lesion in dense breast was much more than that in non-dense breast (P =0.000).In addition,the average ADC values of the lesion in dense breast (0.89±0.12)×10 -3 mm2/s were lower than in non-dense breast (0.95±0.10)×10 -3 mm2/s(P =0.01 6).Conclusion The breast cancer in the dense breast has different MRI findings in comparison with non-dense breast.
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Objective:To analyse the dataflow and clinical flow in Suzhou municipal hospital radiology information system and picture archiving system, presents a set of system integration messages, and describes the effect of each message for the communication. Methods: Follow the framework of IHE and HL7 protocol, the paper uses standard messages to integrate two different systems for patient and study status communication. The integration can meet clinical users’ requirements.Results: Based on many years practice, the integration reached designed target.Conclusion: With further research on standard, the seamless system integration between different systems can help customer to make full use of each system and save more cost in system purchase.