Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification
Impact of Binarization Thresholding and Brightness/Contrast Adjustment Methodology on Optical Coherence Tomography Angiography Image Quantification
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DOI：
10.1016/j.ajo.2019.03.008
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发表时间：
2019-09-01
影响因子：
4.2
通讯作者：
Waheed, Nadia K.
中科院分区：
文献类型：
--
作者：
Mehta, Nihaal;Liu, Keke;Waheed, Nadia K.
目的：二值化是光学相干层析血管成像(OCTA)图像分析中的一项关键技术，但已发表的OCTA研究中所使用的方法并不一致。这项研究评估了OCTA二值化以及亮度和对比度调整的差异是否影响量化测量。设计：前瞻性横断面有效性研究。方法：这是一项单中心研究，检查了11名健康人的21只眼。所有受试者使用扫描源OCTA(Zeiss)进行成像，并比较五种二值化阈值和五种亮度/对比度调节方法的定量测量结果。结果：不同二值化阈值方法的测量结果(P<；0.0001)以及不同直方图调整方法的测量结果(P<；0.0001)有统计学意义。当结合可变的亮度/对比度调整时，二值化阈值产生不同的测量结果。分析方法也影响未平均和平均CC图像之间图像测量的方向性。结论：OCTA图像二值化、阈值和直方图调整的方法显著改变了定量测量和趋势的方向性。从不同的OCTA二值化方法获得的结果应该被视为仅对该给定方法有效。这对使用OCTA测量作为结果测量的临床试验具有重大影响。整个研究界需要就OCTA图像量化的一致方法达成共识，并更多地关注已发表研究中的全面描述方法。((C)2019年由Elsevier Inc.出版)
PURPOSE: Binarization is a critical technique in optical coherence tomography angiography (OCTA) image analysis, but there is no consistency in the method used in published OCTA studies. This study assessed whether differences in OCTA binarization and brightness and contrast adjustments affect quantification measurements.DESIGN: Prospective cross-sectional validity study.METHODS: This was a single-center study examining 21 eyes of 11 healthy individuals. All eyes were imaged using a swept-source OCTA (Zeiss), and quantitative measurements resulting from five binarization thresholding and five brightness/contrast adjustment methods were compared. All measurements were calculated for the superficial plexus and choriocapillaris (CC), as well as unaveraged and averaged en face OCTA images.RESULTS: There were statistically significant differences between measurements from different binarization thresholding methods (P < 0.0001), as well as measurements from different histogram adjustments (P < 0.0001). The binarization thresholds yielded different measurements when combined with variable brightness/contrast adjustments. The method of analysis also affected the directionality of trends in imaging measurements between unaveraged and averaged CC images.CONCLUSIONS: The method of OCTA image binarization thresholding and histogram adjustment significantly alters quantitative measurements and the directionality of trends. Results obtained from different OCTA binarization methods should be seen as valid only for that given method. This has significant consequences for clinical trials using OCTA measurements as outcome measurements. A consensus is needed across the research community for a consistent method for OCTA image quantification and greater attention paid to fully describing methods in published studies. ((C) 2019 Published by Elsevier Inc.)