Improved detection of the central reflex in retinal vessels using a generalized dual-Gaussian model and robust hypothesis testing
Improved detection of the central reflex in retinal vessels using a generalized dual-Gaussian model and robust hypothesis testing
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DOI：
10.1109/titb.2007.897782
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发表时间：
2008-05-01
影响因子：
--
通讯作者：
Roysam, Badrinath
中科院分区：
文献类型：
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作者：
Narasimha-Iyer, Harihar;Mahadevan, Vijay;Roysam, Badrinath
这更新了作者早些时候发表的一篇文章，该文章描述了一种用于检测噪声视网膜眼底图像中的血管系统的健壮框架。我们改进了对血管外观“中空”的“中枢反射”现象的处理。这在视网膜血氧测定仪在570 nm和600 nm处获取的双波长图像中尤为明显。在对血氧含量敏感的600 nm图像中，它是突出的。需要改进这些血管的分割，以改进血氧仪。我们表明，使用广义双高斯模型代替高斯模型来描述血管强度分布会产生显著的改善。我们的方法可以解释中枢反射强度、相对对比度、宽度、方位、尺度和成像噪声的变化。它还可以对常规血管和中枢反射血管进行分类。与CAN等人的算法相比，该方法的灵敏度为72%，而基于单高斯模型的稳健检测算法的灵敏度为60%。三种方法的特异性分别为95%、97%和98%。
This updates an earlier publication by the authors describing a robust framework for detecting vasculature in noisy retinal fundus images. We improved the handling of the "central reflex" phenomenon in which a vessel has a "hollow" appearance. This is particularly pronounced in dual-wavelength images acquired at 570 and 600 nm for retinal oximetry. It is prominent in the 600 nm images that are sensitive to the blood oxygen content. Improved segmentation of these vessels is needed to improve oximetry. We show that the use of a generalized dual-Gaussian model for the vessel intensity profile instead of the Gaussian yields a significant improvement. Our method can account for variations in the strength of the central reflex, the relative contrast, width, orientation, scale, and imaging noise. It also enables the classification of regular and central reflex vessels. The proposed method yielded a sensitivity of 72% compared to 38% by the algorithm of Can et al., and 60% by the robust detection based on a single-Gaussian model. The specificity for the methods were 95%, 97%, and 98%, respectively.