Abstract:Objective To develop three-dimensional (3D) printed tissue compensators for irregular body surface in radiotherapy. Methods Pre-clinical evaluation was made among human phantoms with no tissue compensators, commercially available tissue equivalent bolus, and 3D printed tissue compensators. Perineal computed tomography (CT) images were acquired from the above three human phantoms with the same prescription dose to the same target volume (D95%=100 cGy). Intensity-modulated radiotherapy plans for the three human phantoms were designed using the same treatment planning system. The dosimetric parameters of planning target volume (PTV) were compared between the three plans. The dosimetric parameters were evaluated among 10 patients who were treated with 3D printed tissue compensators. Results The electron density of the selected material was 1.00-1.01. The phantoms with no tissue compensators, commercially available tissue equivalent bolus, and 3D printed tissue compensators had Dmax of 182.9, 118.9, and 114.8 cGy, Dmean of 146.2, 107.7, and 104.1 cGy, and homogeneity index (HI) of 0.565, 0.15, and 0.11 for PTV, respectively. All the 10 patients had highly personalized 3D printed tissue compensators with satisfactory dose homogeneity (HI=0.03-0.15 with a median of 0.06). Five patients with Paget′s disease of penis and scrotum benefited from the support and fixation by 3D printed tissue compensators. Conclusions The highly personalized 3D printed tissue compensators can provide a positioning support for patients and effectively increase the dose to the skin.
Zhang Min,Zhao Bo,Yin Jinpeng et al. Application of new three-dimensional printed tissue compensators in radiotherapy[J]. Chinese Journal of Radiation Oncology, 2017, 26(2): 210-214.
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