Application of deformable image registration in the evaluation of radiation dose to the heart(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第5期
- Page:
- 503-508
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Application of deformable image registration in the evaluation of radiation dose to the heart
- Author(s):
- TONG Ying1; 2; YIN Yong1; CHENG Pinjing2; LU Jie1; LIU Tonghai1; GONG Guanzhong1
- 1. Department of Radiation Physics, Shandong Cancer Hospital Affiliated to Shandong University, Ji’nan 250117, China; 2. School of Nuclear Science and Technology, University of South China, Hengyang 421001, China
- Keywords:
- ; deformable image registration; radiotherapy dosage; heart; left ventricular myocardium
- PACS:
- R734.2；R815
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.05.002
- Abstract:
- Objective To discuss the feasibility of applying deformable image registration for assessing dose-volume parameters and the dosimetry parameters of the heart and the left ventricular myocardium (LVM). Methods The electrocardiogram-gate four-dimensional CT images of 21 patients were analyzed retrospectively. The heart and LVM were delineated on 20 phases of 4DCT images (0%, 5%, [?], 95%). With the use of intensity-based free-form deformable registration algorithm of MIM Maestro, the heart and LVM in minimum volume and minimum dice similarity coefficient (DSC) phase (refer to 0% phase) were deformed to maximum volume and maximum DSC phase. Moreover, the dose was also deformed according to the deformation vector. The variations in the volume, mean dose (Dmean), V20, V30 and V40 of heart and LVM before and after deformation registration were compared. Results The variation rate of heart volume before and after the heart in minimum volume was deformed to maximum volume was reduced from (13.87±2.84)% to (1.72±1.45)% compared to maximum volume. The heart in minimum DSC phase were deformed to maximum DSC phase, and the DSC before and after deformation registration were increased from 0.899±0.014 to 0.950±0.009 compared to maximum DSC phase. Statistical differences were found in the Dmean, V20, V30 and V40 of heart between the maximum volume/maximum DSC phase and the deformation phase (P<0.05). The variation rate of volume before and after LVM in minimum volume phase was deformed to maximum volume phase was reduced from (18.77±6.64)% to (17.38±7.89)% compared to maximum volume, and the volume before and after deformation registration were statistically significant compared to maximum volume (P<0.05). The DSC after LVM in minimum DSC phase was deformed to maximum DSC phase was 0.773±0.052 compared with maximum DSC phase. The Dmean, V20, V30 and V40 of LVM before and after deformation registration were statistically significant compared with maximum DSC phase (P<0.05). Conclusion The variation in dose-volume parameters doesn’t have a linear relationship with the variation in volume and morphology for the heart. The local individualized registration should be considered in cardiac deformation due to the excessive deformation. However, the inconsistency of the volumetric variation and the morphological variation of LVM may be a major factor which leads to the uncertainty in dose-volume evaluation, and therefore the deformation algorithm must be designed with the introduction of multidimensional parameters.
Last Update: 2018-05-22