基于标准剂量CT图像非局部权值先验的低剂量图像恢复  

Low-Dose CT Image Restoration Using a Non-Local Weights Prior from Previous Normal-Dose Scan Image

作　　者：毕一鸣[1] 马建华[1] 路利军[1] 刘楠[1] 黄静[1] 陈武凡[1] 

机构地区：[1]南方医科大学生物医学工程学院医学信息研究所,广东广州510515

出　　处：《电子学报》2010年第5期1146-1151,共6页Acta Electronica Sinica

基　　金：国家973重点基金研究发展规划(No.2010CB732503);国家自然科学基金(No.30730036)

摘　　要：本文提出一种基于标准剂量CT图像非局部权值先验的低剂量图像恢复方法,该方法首先将先前标准剂量图像与低剂量CT图像配准,并对低剂量CT图像进行预处理以抑制部分噪声,随后利用非局部均值的思想计算配准后的先前标准剂量CT图像的权值矩阵,基于该权值矩阵对预处理后的低剂量CT图像进行加权均值滤波.仿真实验和临床脑灌注数据实验表明,本文方法在消除低剂量CT图像噪声和伪影的同时,还可提升图像分辨率,对临床脑灌注CT扫描的疾病诊断中尤为有效.A novel approach is proposed to improve low-dose CT image quality by a non-local weighs prior which is acquired from previous normal-dose scan. First, we align two images--the low-dose and the previous normal-dose scan image, and filter the low-dose image to suppress noise. Then,the weight malrix of the registered normal-dose image is calculated by the non-local means weighting formula, and the low-dose image is restorated using this weight matrix as a prior. Simulated phantom and perfusion data experiment results demonstrate a highly quality improvement in terms of suppressing noise-induced streak artifacts and preserving resolution of the low-dose image using the proposed method. The proposed method is especially effective for clinical short-term repeated CT scan, such as perfusion and radiation therapy.

关 键 词：低剂量CT 图像恢复 非局部权值先验 重复CT扫描 

分 类 号：R391.4[医药卫生—基础医学]