원문정보
초록
영어
Background: Stereotactic ablative radiotherapy (SABR) plans in prostate cancer are compared and analyzed to investigate the low magnetic effect (0.35 T) on the dose distribution, with various dosimetric parameters according to low magnetic field. Materials and Methods: Twenty patients who received a 36.25 Gy in five fractions using the MR-IGRT system (ViewRay) were studied. For planning target volume (PTV), the point mean dose (Dmean), maximum dose (Dmax), minimum dose (Dmin) and volumes receiving 100% (V100%), 95% (V95%), and 90% (V90%) of the total dose. For organs-at-risk (OARs), the differences compared using Dmax, V50%, V80%, V90%, and V100% of the rectum; Dmax, V50%, V30Gy, V100% of the bladder; and V30Gy of both left and right femoral heads. For both the outer and inner shells near the skin, Dmean, Dmin, and Dmax were compared. Results and Discussion: In PTV analysis, the maximum difference in volumes (V100%, V95%, and V90%) according to low magnetic field was 0.54 ± 0.63% in V100%. For OAR, there was no significant difference of dose distribution on account of the low magnetic field. In results of the shells, although there were no noticeable differences in dose distribution, the average difference of dose distribution for the outer shell was 1.28 ± 1.08 Gy for Dmax. Conclusion: In the PTV and OARs for prostate cancer, there are no statistically-significant differences between the plan calculated with and without a magnetic field. However, we confirm that the dose distribution significantly increases near the body shell when a magnetic field is applied.
목차
Introduction
Materials and Methods
1. Treatment system (ViewRay)
2. Description of prostate plans
3. Statistics Analysis
4. Plan evaluation by various parameters
Results
1. The difference of dose distribution in PTV
2. The difference of dose distribution in OARs
3. The difference of dose distribution near the skin
Discussion
Conclusion
Acknowledgements
References