基于micro-CT图像的骨复合体素模型建模研究

Research on Modeling of Skeletal Composite Voxel Model Based on Micro-CT Image

已建立的人体体素模型中,骨松质均采用均匀模型代替,使骨剂量的计算精度受到影响。目前国际上利用白种人骨松质的NMR、micro-CT图片开展了骨微观模型的建模及剂量学研究,但我国尚未开展这方面的研究。本文利用micro-CT成像,建立了基于中国人骨松质的骨微观模型,同时与已建立的中国成年男性参考体素模型中的宏观骨模型相结合,建立了骨复合体素模型。利用该模型初步计算了骨盆骨小梁体源、骨小梁面源和红骨髓源对骨内膜的电子吸收分数。计算结果显示,基于中国人骨松质的骨微观模型计算的吸收分数曲线变化趋势与白种人的计算结果一致,最大差异分别为5.7%、1.4%和2%。

Spongiosa in existing human voxel phantom is replaced by homogeneous model.This affects the accuracy of skeletal dosimetry calculations.At present NMR and micro-CT images of Caucasian spongiosa are used in the research of establishment and dosimetry of skeletal microscopic model internationally.But there is currently no research on this area in China.In the present work,micro-CT images were used to establish the skeletal microscopic model based on the Chinese spongiosa.And the skeletal composite voxel model was established by combining skeletal microscopic model with macroscopic model existed in Chinese reference adult male voxel model.Preliminary calculations of electron absorbed fractions for the pelvis form trabecular bone volume,trabecular bone surface and red marrow to endosteum were carried out by using skeletal composite voxel model.The results show that the variation tendencies of electron absorbed fraction curves are accordant with the results of Caucasian.The maximum differences are 5.7%,1.4%and 2%respectively.