WU Zhiqin,ZHANG li,YU Jianyi, et al. Comparative study on set-up errors with different registration algorithm for lung cancer undergone image guided radiation therapy[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2014, 44(11): 822-.
Abstract：Objective: To investigate the accuracy of two different image registration algorithms for the setup error study in the treatment of lung cancer with image-guided radiation therapy (IGRT) technique. Methods: Forty-three lung cancer patients were treated with cone beam CT (CBCT) undergone image guided. Elekta Synergy linear accelerator radiation (KV-CBCT) was applied to investigate the setup discrepancy before the treatment, after online correction and the end of delivery. The difference in bone alignment, and grey value alignment were compared between CBCT images obtained by the reconstruction and original plan system CT images. The rotational error of the X, Y, Z-axis in the horizontal direction and the error of X, Y, Z in rotation direction were analyzed. Results: Total of 114 sets of CBCT images were scanned for 43 patients with lung cancer. The setup errors with bone-based registration and grey-based registration in the translational direction of the X, Y, and Z axis were (-0.297±3.137) mm and (0.377±2.958) mm, (-1.415±0.5.313) mm and (0.719±5.451) mm, (0.632±3.033)mm and (-0.679±2.982) mm. The setup in rotational direction of GX, GY, and GZ for bone-based and grey-based registration were (-0.469±1.605) ° and (-0.493±1.461) °, (-0.203±1.4 31) ° and (0.35±1.424) °, (0.134±1.478) °
and (0.196±1.348) °. Except in the rotational X and Z direction, there was significant difference between bone-based and grey-based registration algorithm. Conclusion: The two registrations all can be selected in lung cancer treatment with image guided radiation therapy (IGRT). It is suggested that the bone registration auxiliary after gray alignment is necessary.
