ABSTRACT
To study an automatic plan(AP) method for radiotherapy after breast-conserving surgery based on TiGRT system and and compare with manual plan (MP). The dosimetry parameters of 10 patients and the evaluation of scoring table were analyzed, it was found that the targets dose of AP were better than that of MP, but there was no statistical difference except for CI, The V5, V20 and V30 of affected lungs and whole lungs in AP were lower than all that in MP, the Dmean of hearts was slightly higher than that of MP, but the difference was not statistically significant, the MU of AP was increase by 16.1% compared with MP, the score of AP evaluation was increase by 6.1% compared with MP. So the AP could be programmed and automated while ensuring the quality of the plan, and can be used to design the plans for radiotherapy after breast-conserving surgery.
Subject(s)
Female , Humans , Breast Neoplasms/surgery , Mastectomy, Segmental , Organs at Risk , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-ModulatedABSTRACT
Objective:To study the clinical feasibility and advantages of the RapidPlan module based on Halcyon 2.0 ring medical linear accelerator in the design of volumetric modulated arc therapy (VMAT) plans after cervical cancer surgery.Methods:The data of 98 clinical cervical cancer cases were selected from the database, and VMAT artificial radiotherapy plans were designed based on Halcyon 2.0. Then, the designed plans were imported into the RapidPlan module to train the module for a prediction model with high goodness of fit. Another 20 patients after cervical cancer surgery were selected as the validation set to compare the differences in dosimetry, plan consistency, and plan execution efficiency between the manual plans and RapidPlan automatic plans.Results:The RapidPlan automatic plans could obtain dose distribution of target volume and organs at risk with the same quality as the manual plans. The RapidPlan automatic plans provided slightly inferior protection of the femoral head but superior protection of the spinal cord compared to the manual plans, and the difference was statistically significant ( t = 4.71, P<0.001). The average MU of the RapidPlan automatic plans was 687.46, which was lower than that of the manual plan (815.34), and the difference was statistically significant ( t = 6.09, P < 0.05). The portal dosimetry (PD) verification revealed that the average γ passing rate (1 mm/1%) of the RapidPlan automatic plans was 89.48%and that of the manual plans was 88.22%, and the difference was statistically significant ( t = 3.35, P < 0.05). Conclusion:RapidPlan automatic plans based on the Halcyon 2.0 platform can meet the clinical needs of the VMAT program for cervical cancer and has certain advantages.
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Objective To develop and evaluate an automatic intensity-modulated radiation therapy (IMRT) program for cervical cancer based on a database of overlap volume histogram (OVH) and high-quality cervical IMRT plans for previously-treated patients.Methods A database consisting of high-quality IMRT plans and OVHs from 200 cervical cancer patients was established.OVHs of another 26 cervical cancer patients were converted into gray level images to calculate the image similarity compared with those from the database.The planning optimization function of the patients from the database with the highest image similarity was selected and inherent Pinnacle3 scripts were utilized to automatically generate IMRT plan.Finally,the dosimetric parameters,plan quality and design time were statistically compared between the automatic and manual plans.Results The target coverage,conformity index and homogeneity index did not significantly differ between two plans (all P＞0.05).The V40,V45 and mean dose for the rectum in the automatic plans were significantly decreased by 6.1％,1.3％ and 50.7 cGy than those in the manual plans (all P＜0.05).Compared with the manual plans,the mean dose for the intestine and femur in the automatic plans were significantly reduced by 31.7 cGy and 188.9 cGy (both P＜0.05),whereas the mean dose for the ilium was slightly decreased by 92.3 cGy in the automatic plans (P＞ 0.05).The plan design time was shortened by 71％ in the automatic plans.Conclusions The automatic IMRT plans based on a database of OVH and high-quality IMRT plans can not only significantly shorten the plan design time,but also reduce the irradiated dose of normal tissues without compromising the target coverage and conformity index.
ABSTRACT
Objective@#To develop and evaluate an automatic intensity-modulated radiation therapy (IMRT) program for cervical cancer based on a database of overlap volume histogram (OVH) and high-quality cervical IMRT plans for previously-treated patients.@*Methods@#A database consisting of high-quality IMRT plans and OVHs from 200 cervical cancer patients was established. OVHs of another 26 cervical cancer patients were converted into gray level images to calculate the image similarity compared with those from the database. The planning optimization function of the patients from the database with the highest image similarity was selected and inherent Pinnacle3 scripts were utilized to automatically generate IMRT plan. Finally, the dosimetric parameters, plan quality and design time were statistically compared between the automatic and manual plans.@*Results@#The target coverage, conformity index and homogeneity index did not significantly differ between two plans (all P>0.05). The V40, V45 and mean dose for the rectum in the automatic plans were significantly decreased by 6.1%, 1.3% and 50.7 cGy than those in the manual plans (all P<0.05). Compared with the manual plans, the mean dose for the intestine and femur in the automatic plans were significantly reduced by 31.7 cGy and 188.9 cGy (both P<0.05), whereas the mean dose for the ilium was slightly decreased by 92.3 cGy in the automatic plans (P>0.05). The plan design time was shortened by 71% in the automatic plans.@*Conclusions@#The automatic IMRT plans based on a database of OVH and high-quality IMRT plans can not only significantly shorten the plan design time, but also reduce the irradiated dose of normal tissues without compromising the target coverage and conformity index.
ABSTRACT
Objective To compare the automatic and manual plans of intensity-modulated radiation therapy ( IMRT ) for nasopharyngeal carcinoma and investigate whether the automatic plan possesses advantages over the manual plan. Methods Clinical data of 97 nasopharyngeal carcinoma patients were retrospectively analyzed. All patients received IMRT with Eclipse treatment planning system (Version 11. 0) using manual optimization. The same plans were optimized successively in Pinnacle3( version 9. 10 ) treatment planning system using automatic plan software package module (provided by Prof. Zhang XD from MD Anderson Cancer Center).The D95(dose in 95% of planning target volume,PTV),homogeneity index, conformal index and normal organ dose were statistically compared between two plans. Results The PTV coverage and homogeneity did not significantly differ between two plans. Compared with the manual plan,the automatic plan could more effectively protect the normal organs. Two plans significantly differed in a majority of organ at risk (OAR).The mean dose was decreased by 270-1870 cGy. Conclusions For nasopharyngeal carcinoma patients,IMRT via the automatic plan can meet the clinical requirement for target prescription dose and reduce the dose of normal organs.