A morphological image processing method to improve the visibility of pulmonary nodules on chest radiographic images
A morphological image processing method to improve the visibility of pulmonary nodules on chest radiographic images
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DOI：
10.1016/j.bspc.2019.101744
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发表时间：
2020-03-01
影响因子：
5.1
通讯作者：
Kimori, Yoshitaka
中科院分区：
文献类型：
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作者：
Kimori, Yoshitaka
肺部结节影是肺癌的特征性表现。然而，结节状阴影常常以非常弱的对比度出现。目标结节阴影经常与对比度强的阴影重叠，例如心脏或肋骨的阴影;因此，难以用普通的对比度增强方法强调目标区域。在这篇文章中，一种新的肺结节增强方法，使用形态减法的基础上修改的h-dome变换。该方法由两部分组成：预处理步骤和结节增强处理。前者减少了背景亮度的不均匀，后者强调了结节。利用该方法，利用结节的形状信息来强调肺结节区域，而抑制了具有不同形状的结节周围区域的强调。该方法还检测结节的边界以及周围解剖学上正常结构的边缘。所提出的方法的性能已被验证结节增强实验使用合成和实际的胸部放射图像从公共数据库。此外，所提出的方法的效率进行了测试，通过使用对比度改善指数（CII），这是一个指标，在结节区域及其周围的对比度的改善，并与现有的对比度强调方法得到的结果进行了定量比较。所提出的方法具有最高的CII值，从而证实了该方法的对比度强调效果。(C)2019爱思唯尔有限公司版权所有。
A pulmonary nodular shadow on a chest radiographic image is characteristic of lung cancer. However, nodular shadows often appear with very weak contrast. The target nodule shadow often overlaps with a shadow with strong contrast, such as that of the heart or rib; thus, it is difficult to emphasize the target region with ordinary contrast enhancement methods. In this article, a new pulmonary nodule enhancement method using a morphological subtraction method based on a modification of the h-dome transform is described. This method consists of two parts: a preprocessing step and nodule enhancement processing. The former reduces the uneven brightness of the background, and the latter emphasizes the nodule. With this method, the pulmonary nodule region is emphasized with the use of shape information of the nodule, whereas emphasis of the regions surrounding the nodule with different shapes is suppressed. This method also detects the boundary of the nodule as well as the edges of the surrounding anatomically normal structures. The performance of the proposed method has been verified by nodule enhancement experiments using synthetic and actual chest radiographic images from a public database. Furthermore, the efficiency of proposed method was tested by using contrast improvement index (CII), which is an index of improvement in contrast in the nodule region and its surroundings, and the results were quantitatively compared with those obtained from existing contrast emphasis methods. The proposed method has the highest value of CII, thereby confirming the effect of the contrast emphasis with this method. (C) 2019 Elsevier Ltd. All rights reserved.