摘要
This study compares and analyzes stereotactic radiotherapy using tomotherapy and linac-based fractionated stereotactic radiotherapy in the treatment of intra-cranial tumors,according to some cases.In this study,linac-based fractionated stereotactic radiotherapy and tomotherapy treatment were administered to five patients diagnosed with intra-cranial cancer in which the dose of 18–20 Gy was applied on 3–5 separate occasions.The tumor dosing was decided by evaluating the inhomogeneous index （II） and conformity index （CI）.Also,the radiation-sensitive tissue was evaluated using low dose factors V1,V2,V3,V4,V5,and V10,as well as the non-irradiation ratio volume （NIV）.The values of the II for each prescription dose in the linacbased non-coplanar radiotherapy plan and tomotherapy treatment plan were （0.125±0.113） and （0.090±0.180）,respectively,and the values of the CI were （0.899±0.149） and （0.917±0.114）,respectively.The low dose areas,V1,V2,V3,V4,V5,and V10,in radiation-sensitive tissues in the linac-based non-coplanar radiotherapy plan fell into the ranges 0.3%–95.6%,0.1%–87.6%,0.1%–78.8%,38.8%–69.9%,26.6%–65.2%,and 4.2%–39.7%,respectively,and the tomotherapy treatment plan had ranges of 13.6%–100%,3.5%–100%,0.4%–94.9%,0.2%– 82.2%,0.1%–78.5%,and 0.3%–46.3%,respectively.Regarding the NIV for each organ,it is possible to obtain similar values except for the irradiation area of the brain stem.The percentages of NIV10%,NIV20%,and NIV30%for the brain stem in each patient were 15%–99.8%,33.4%–100%,and 39.8%–100%,respectively,in the fractionated stereotactic treatment plan and 44.2%–96.5%,77.7%–99.8%,and 87.8%–100%,respectively,in the tomotherapy treatment plan.In order to achieve higher-quality treatment of intra-cranial tumors,treatment plans should be tailored according to the isodose target volume,inhomogeneous index,conformity index,position of the tumor upon fractionated stereotactic radiosurgery,and radiation dosage for radiation-sensitive tissues.
This study compares and analyzes stereotactic radiotherapy using tomotherapy and linac-based fractionated stereotactic radiotherapy in the treatment of intra-cranial tumors,according to some cases.In this study,linac-based fractionated stereotactic radiotherapy and tomotherapy treatment were administered to five patients diagnosed with intra-cranial cancer in which the dose of 18–20 Gy was applied on 3–5 separate occasions.The tumor dosing was decided by evaluating the inhomogeneous index （II） and conformity index （CI）.Also,the radiation-sensitive tissue was evaluated using low dose factors V1,V2,V3,V4,V5,and V10,as well as the non-irradiation ratio volume （NIV）.The values of the II for each prescription dose in the linacbased non-coplanar radiotherapy plan and tomotherapy treatment plan were （0.125±0.113） and （0.090±0.180）,respectively,and the values of the CI were （0.899±0.149） and （0.917±0.114）,respectively.The low dose areas,V1,V2,V3,V4,V5,and V10,in radiation-sensitive tissues in the linac-based non-coplanar radiotherapy plan fell into the ranges 0.3%–95.6%,0.1%–87.6%,0.1%–78.8%,38.8%–69.9%,26.6%–65.2%,and 4.2%–39.7%,respectively,and the tomotherapy treatment plan had ranges of 13.6%–100%,3.5%–100%,0.4%–94.9%,0.2%– 82.2%,0.1%–78.5%,and 0.3%–46.3%,respectively.Regarding the NIV for each organ,it is possible to obtain similar values except for the irradiation area of the brain stem.The percentages of NIV10%,NIV20%,and NIV30%for the brain stem in each patient were 15%–99.8%,33.4%–100%,and 39.8%–100%,respectively,in the fractionated stereotactic treatment plan and 44.2%–96.5%,77.7%–99.8%,and 87.8%–100%,respectively,in the tomotherapy treatment plan.In order to achieve higher-quality treatment of intra-cranial tumors,treatment plans should be tailored according to the isodose target volume,inhomogeneous index,conformity index,position of the tumor upon fractionated stereotactic radiosurgery,and radiation dosage for radiation-sensitive tissues.
基金
Supported by Nuclear R&D Programs from Ministry of Education,Science,and Technology in Republic of Korea
