Improving low-dose abdominal CT images by Weighted Intensity Averaging over Large-scale Neighborhoods
Improving low-dose abdominal CT images by Weighted Intensity Averaging over Large-scale Neighborhoods
复制标题
通过大规模邻域的加权强度平均来改善低剂量腹部 CT 图像
DOI：
10.1016/j.ejrad.2010.07.003
复制
发表时间：
2011-11-01
影响因子：
3.3
通讯作者：
Yu, Xiaoe
中科院分区：
文献类型：
--
作者：
Chen, Yang;Chen, Wufan;Yu, Xiaoe
目的：虽然低剂量CT(LDCT)图像在放射学操作中非常受欢迎，但它往往会受到量子噪声和非平稳伪影的严重影响。为了对腹部LDCT图像进行改进，提出了一种基于大规模邻域的加权强度平均方法(WIA-LN)。材料和方法：在WIA-LN方法的实现过程中，处理后的像素强度被自适应地计算为周围结构相似的像素在整个大尺度邻域中的加权强度平均值。体模和临床腹部CT图像均来自西门子16排CT，分别以标准和80%缩减管电流时间积(150 mA S和30 mA S，分别对应于标准剂量和低剂量方案)获得。结果：提出的WIA-LN方法具有更好的视觉和定量性能。与原始LDCT和标准剂量CT(SDCT)图像相比，该方法在抑制噪声/伪影、保持对比度和检测肝囊肿等方面均有显著改善(P<；0.05)。结论：在管电流降至标准管电流设置的五分之一左右的情况下，该方法仍可获得临床可接受的图像。皇冠版权所有(C)2010由爱思唯尔爱尔兰有限公司出版。保留所有权利。
Purpose: Though highly desirable in radiologic procedures, low-dose CT (LDCT) images tend to be severely degraded by quantum noise and non-stationary artifacts. The purpose of this paper is to improve the abdominal LDCT images by the approach of Weighted Intensity Averaging over Large-scale Neighborhoods (WIA-LN).Materials and methods: In the implementation of the proposed WIA-LN method, the processed pixel intensities are adaptively calculated as the weighted intensity averaging of the pixels with similar surrounding structures throughout a large-scale neighborhood. Both phantom and clinical abdominal CT images from a 16 detector rows Siemens CT were acquired at standard and 80% reduced tube current time products (150 mA s and 30 mA s corresponding to standard-dose and low-dose protocols, respectively). Visual comparison, statistical qualitative analysis (image quality scores and hepatic cyst diagnosis), and quantitative calculation (noise and contrast-to-noise ratio) are made.Results: Better vision and quantitative performance are realized using the proposed WIA-LN method. Compared to original LDCT and standard-dose CT (SDCT) images, statistically significant improvement of noise/artifacts suppression, contrast preservation and hepatic cyst detection in LDCT images are achieved by using the proposed method (P < 0.05).Conclusion: With the tube current reduced to approximate one-fifth of the standard tube current setting, clinically acceptable images can still be obtained by using the proposed method. Crown Copyright (C) 2010 Published by Elsevier Ireland Ltd. All rights reserved.