基于C型臂超短扫描路径锥束投影的图像合成*

摘要

背景：CT 成像质量的优劣不仅取决于仪器的精密性和先进性，在很大程度上也取决于重建算法，由二维扇束扫描向三维锥束扫描是 CT 技术的发展方向，因此，寻找一种合适的锥束重建算法具有无法忽略的意义。目的：探讨基于 C 型臂超短扫描路径锥束投影的图像合成，为实现基于 C 型臂2D 投影图像的3D 模型重建提供算法支持。方法：由第一作者于2012年3至5月检索 PubMed 数据库、CNKI 系列数据库及万方数据库1990年至2011年文献。检索词为“C 型臂，超短扫描路径，FDK 算法，有限角锥形束三维重建，超短扫描扇束重建算法”，检索文章的语言种类为中文和英文。计算机初检得到58篇文献，其中19篇符合纳入标准被保留。结果与结论：基于 C 型臂2D 投影图像的3D 模型重建必须进行三维模型的重建，目前应用最为广泛的的三维图像重建方法仍然是 FDK。但是 FDK 算法适用于全路径，对超短路径而言不能直接采用，而通过将二维扇束重建算法推广到三维空间中而获得的短扫描轨迹的 FDK 类型锥束重建算法可对采集到的锥束投影数据进行感兴趣区域重建。未来的研究可针对减少噪声等干扰数据对重建质量造成的影响进行探讨。%BACKGROUND: The merit of CT imaging quality not only depends on the precision and advance of the instrument, but also depends on the reconstruction algorithm. Developing from the two dimensional fan bunch scan to the three-dimensional cone bunch scan is the development trend of CT technology. Therefore, looking for a suitable cone bunch reconstruction algorithm has a great significance. OBJECTIVE: To explore the cone projection image synthesis based on C-arm super short scan path in order to provide the algorithm support for the realization of C-arm based two-dimensional projection image and three-dimensional model rebuilding.METHODS: The PubMed database, CNKI database and Wanfang database were searched by the first author from March 2012 to May 2012 for the related articles published from 1990 to 2011. The key words were “C-arm, super short scan path, FDK algorithm, limited cone angle of three-dimensional reconstruction, super short scanning fan bunch of reconstruction algorithm”, the language of the retrieved articles were Chinese and English. A total of 58 articles were obtained after initial screen, and final y 19 articles that met the inclusion criteria were included. RESULTS AND CONCLUSION: The three-dimensional model reconstruction based on C-arm two-dimensional projection image must be treated with three-dimensional model reconstruction. Currently, the most widely used three-dimensional image reconstruction method was FDK algorithm. However, the FDK algorithm only suitable for the whole pathway, and cannot directly used for super short scan path. The short scanning trajectory FDK cone bunch reconstruction algorithm obtained through extending the two-dimensional fan bunch reconstruction algorithm to the three-dimensional space could reconstruct the interest region of the col ected cone bunch projection data. Future studies may explore the effect of noise reducing and other interference data on the reconstruction quality.