SU-C-BRB-02: Exploring the Correlation Between 3D Spatial Dose Distribution and Toxicity in Normal Tissue

2012 ◽  
Vol 39 (6Part2) ◽  
pp. 3601-3601
Author(s):  
Z Saleh ◽  
A Apte ◽  
G Sharp ◽  
S Rao ◽  
N Lee ◽  
...  
Keyword(s):  
Dose Distribution ◽  
Normal Tissue

scholarly journals Dosimetric and radiobiological comparison of treatment plan between CyberKnife and EDGE in stereotactic body radiotherapy for pancreatic cancer

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhi-tao Dai ◽  
Li Ma ◽  
Ting-ting Cao ◽  
Lian Zhu ◽  
Man Zhao ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Spinal Cord ◽  
Stereotactic Body Radiotherapy ◽  
Dose Distribution ◽  
Normal Tissue ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Locally Advanced ◽  
Conformity Index ◽  
Homogeneous Dose

AbstractTo perform a comparison of the different stereotactic body radiotherapy (SBRT) plans between the Varian EDGE and CyberKnife (CK) systems for locally advanced unresectable pancreatic cancer. Fifteen patients with pancreatic cancer were selected in this study. The median planning target volume (PTV) was 28.688 cm3 (5.736–49.246 cm3). The SBRT plans for the EDGE and CK were generated in the Eclipse and Multiplan systems respectively with the same contouring and dose constrains for PTV and organs at risk (OARs). Dose distributions in PTV were evaluated in terms of coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), and gradient index (GI). OARs, including spinal cord, bowel, stomach, duodenum and kidneys were statistically evaluated by different dose-volume metrics and equivalent uniform dose (EUD). The volume covered by the different isodose lines (ISDL) ranging from 10 to 100% for normal tissue were also analyzed. All SBRT plans for EDGE and CK met the dose constraints for PTV and OARs. For the PTV, the dosimetric metrics in EDGE plans were lower than that in CK, except that D99 and GI were slightly higher. The EDGE plans with lower CI, nCI and HI were superior to generate more conformal and homogeneous dose distribution for PTV. For the normal tissue, the CK plans were better at OARs sparing. The radiobiological indices EUD of spinal cord, duodenum, stomach, and kidneys were lower for CK plans, except that liver were higher. The volumes of normal tissue covered by medium ISDLs (with range of 20–70%) were lower for CK plans while that covered by high and low ISDLs were lower for EDGE plans. This study indicated that both EDGE and CK generated equivalent plan quality, and both systems can be considered as beneficial techniques for SBRT of pancreatic cancer. EDGE plans offered more conformal and homogeneous dose distribution for PTV, while the CK plans could minimize the exposure of OARs.

scholarly journals Investigation of the Optimal Mouthpiece Material for Proton Therapy of Head and Neck Cancer

2021 ◽  
Author(s):  
Masaaki Suzuka ◽  
Takashi Mori ◽  
Shigeru Yamano ◽  
Akiko Takeuchi ◽  
Tomoka Shima ◽  
...  
Keyword(s):  
Head And Neck ◽  
Proton Therapy ◽  
Dose Distribution ◽  
Normal Tissue ◽  
Dental Materials ◽  
Ethylene Vinyl Acetate ◽  
Ct Value ◽  
Treatment Plans ◽  
Acetate Copolymer ◽  
Ethylene Vinyl Acetate Copolymer

Abstract Purpose: To investigate how the materials of mouthpieces used for proton therapy of head and neck cancer affect the dose distribution in surrounding normal tissue by focusing on the CT values of the materials.Methods: Six dental materials were used to measure CT values: temporary relining resin, tissue conditioner, vinyl polysiloxane, thermoplastic ethylene vinyl acetate copolymer splint, silicone rubber impression material, and a composite impression material. Among these materials, three of the dental materials were investigated further: one material with the CT value closest to water, and the materials with the highest and lowest CT values. Based on these results, we investigated the effect of the CT value of the mouthpiece on the dose distribution in 17 cases in which a mouthpiece was used during proton therapy for head and neck cancers, the treatment plans were recalculated by changing the CT values of the mouthpiece to that of the three identified dental materials. For each cancer case, the irradiation dose to normal tissue was calculated for the treatment plans. The evaluation indices were set to the mandible max dose (GyE), the mandible mean dose (GyE), the volume of the mandible irradiated above 60 GyE (mandible V-60GyE), the parotid affected side mean dose (GyE), the parotid unaffected side mean dose (GyE), and the oral mean dose (GyE). The Wilcoxon’s rank sum test was used to analyze the significance of the differences between treatment plans.Results: The temporary relining resin with the CT value closest to water was 36.9 HU, the vinyl polysiloxane with the highest CT value was 985 HU, and the thermoplastic ethylene vinyl acetate copolymer splint with the lowest CT value was -89.7 HU. The maximum absolute difference among the treatment plans per case was 4.18 GyE for the oral mean dose. The radiation dose for the evaluation indices did not differ significantly among the treatment plans. Conclusion: In the range of CT values from -89.7 HU to 985.0 HU covered in this study, the effect of the CT value of the mouthpiece on the dose distribution may be considered to have no clinical impact.

scholarly journals Distribution of Water Phantom BNCT Cyclotron based Using PHITS

2019 ◽  
Vol 4 (1) ◽  
pp. 1-7
Author(s):  
Siti Maimanah ◽  
Siti Maimanah ◽  
Susilo Susilo ◽  
Yohannes Sardjono
Keyword(s):  
Cancer Cells ◽  
Dose Distribution ◽  
Normal Tissue ◽  
Cellular Level ◽  
Healthy Tissue ◽  
Research Purpose ◽  
Powerful Method ◽  
Water Phantom

This research purpose is to estimate the dose distribution of BNCT in water phantom. Some common methods in the treatment of cancer such as brakhiterapi, surgery, chemotherapy, and radiotherapy still have the risk of damaging healthy tissue around cancer cells. BNCT is a selectively-designed technique by targeting high-loaded LET particles to tumors at the cellular level. BNCT proves to be a powerful method of killing cancer without damaging normal tissue. The source of the neutron used from the cyclotron dose in water phantom with the size of 30 cm x 30 cm x 30 cm was calculated using PHITS program. The result from the simulation is that boron water panthom has a dosimetri higher than phantom water without boron.

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