Schlueter F J, Wang G, Hsieh P S, Brink J A, Balfe D M, Vannier M W
Mallinckrodt Institute of Radiology, Washington University School of Medicine, St Louis, MO 63110.
Radiology. 1994 Nov;193(2):413-8. doi: 10.1148/radiology.193.2.7972755.
To assess the feasibility of digital deconvolution techniques to improve longitudinal resolution of spiral computed tomography (CT) multiplanar reformations and evaluate how technical factors in deconvolution affect longitudinal resolution, noise, and edge ringing.
Longitudinal line spread function (LSF) of the system was estimated from longitudinal reformations of transaxial spiral CT images of a step test phantom. By using the estimated LSF, longitudinal reformations of the phantom and three clinical spiral CT studies were deconvolved by the methods of Wiener filtering and constrained iterative deconvolution. Edge ringing and image noise were quantified for Wiener filtering and constrained iterative deconvolution.
Longitudinal reformations were substantially deblurred and resolution improved after deconvolution. Anatomic boundaries in clinical images were more clearly delineated after restoration. The methods of Wiener deconvolution and constrained iterative deconvolution improved the sharpness of the phantom step boundary at the expense of increased edge ringing and image noise.
In longitudinal spiral CT reformations, blurring along the longitudinal axis can be reduced by Wiener filtering or constrained iterative deconvolution.
评估数字反卷积技术改善螺旋计算机断层扫描（CT）多平面重建纵向分辨率的可行性，并评估反卷积中的技术因素如何影响纵向分辨率、噪声和边缘振铃。
通过对阶梯测试体模的横断面螺旋CT图像进行纵向重建，估算系统的纵向线扩散函数（LSF）。利用估算出的LSF，采用维纳滤波和约束迭代反卷积方法对体模和三项临床螺旋CT研究的纵向重建进行反卷积处理。对维纳滤波和约束迭代反卷积的边缘振铃和图像噪声进行量化。
反卷积后纵向重建明显去模糊，分辨率提高。临床图像中的解剖边界在恢复后更清晰地显示出来。维纳反卷积和约束迭代反卷积方法提高了体模阶梯边界的清晰度，但代价是边缘振铃和图像噪声增加。
在纵向螺旋CT重建中，可通过维纳滤波或约束迭代反卷积减少沿纵轴的模糊。
