A comparison of rigid and deformable image registration at end-inhale and end-exhale phases based on 4DCT images for radiotherapy after breast-conserving surgery
10.3760/cma.j.issn.1004-4221.2017.11.008
- VernacularTitle:保乳术后基于4DCT的0％时相及50％时相配准方式比较
- Author:
Aiping ZHANG
1
;
Jianbin LI
;
Wei WANG
;
Yanluan GUO
;
Qian SHAO
;
Min XU
Author Information
1. 济南大学/山东省医学科学院医学与生命科学学院
- Keywords:
External partial breast irradiation;
Four-dimensional computed tomography;
Rigid image registration;
Deformable image registration;
Respiratory movement;
Breast neoplasms
- From:
Chinese Journal of Radiation Oncology
2017;26(11):1280-1284
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the geometric differences of gross tumor volumes(GTV)and displacements of selected clips propagated by rigid image registration(RIR)and deformable image registration (DIR)at end-inhale phase(CT0)and end-exhale phase(CT50)based on four-dimensional computed tomography(4DCT)of the whole breast after breast-conserving surgery(BCS). Methods Forty-four patients who underwent 4DCT simulation scans after BCS were selected. The GTV and displacements of selected metal clips at CT0and CT50were manually delineated by the same radiotherapy physician. Subsequently,the GTV and displacements of selected clips from CT0images were transformed and propagated to CT50images using RIR and DIR.The geometric differences of GTV and displacements of surgical clips from DIR were compared with those from RIR based on the dice similarity coefficient(DSC)and the displacements of the center of mass(COM)in the three-dimensional(3D)directions. Results The mean DSC was 0.86± 0.04 for RIR and 0.87± 0.04 for DIR(P=0.000).The displacements of COM in 3D directions from RIR were significantly greater than those from DIR(1.22 mm vs. 1.10 mm,P=0.000).In the anterior-posterior direction,the displacements from RIR were significantly greater than those from DIR for both GTV and selected clips(P=0.000).However,in the left-right and superior-inferior directions,there were no significant differences in displacements between RIR and DIR for both GTV and the selected clips(all P>0.05). Conclusions DIR can improve the overlap for GTV registration from 4DCT scans at CT0and CT50.Furthermore,DIR is superior to RIR in reflecting GTV and the displacements of selected clips in anterior-posterior direction induced by respiratory movement.
