基于眼前节结构信息的OCT和OCTA图像运动伪影校正  

Structural-Information-Based Motion Artifact Correction for OCT and OCTA Images of Anterior Segments

作　　者：钟浩哲 曹良齐 张晓[1] Zhong Haozhe;Cao Liangqi;Zhang Xiao(School of Medical Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学医学技术学院,北京100081

出　　处：《光学学报》2024年第19期273-281,共9页Acta Optica Sinica

基　　金：国家自然科学基金(62275018,61905015)。

摘　　要：在眼前节的三维光学相干层析成像(3D-OCT)和光学相干层析血管成像(OCTA)过程中,由成像对象的呼吸、心跳等非自主运动造成的运动伪影现象严重影响着成像质量。提出一种基于眼前节结构信息来估计成像对象运动曲线进而实现运动伪影校正的方法。利用所提方法分别对角膜的C-scan以及虹膜的OCTA图像进行分析,从而获得慢轴方向上的相对运动,并将二者结合得到准确的运动曲线,并以此为参照校正OCT图像中的运动伪影。作为演示,将该方法应用到小鼠眼前节3D-OCT和OCTA图像的运动伪影校正中,结果证明,所提方法能够有效地消除运动伪影并提升图像质量。所提方法的计算量小且无需引入额外硬件设备和冗余扫描方式,能够满足眼前节运动伪影校正的需要,对提升眼前节3D-OCT及OCTA扫描效果具有重要意义。Objective Optical coherence tomography(OCT)and optical coherence tomography angiography(OCTA)are helpful and powerful optical imaging modalities characterized by high speed,non-invasive diagnosis,and high resolution.They have been widely employed in biomedicine testing,especially in ophthalmic disease diagnosis.With the development of OCT and OCTA,the image quality in ophthalmic fields has been greatly improved,but it still faces a few challenges in practice.One of the serious problems is the artifacts caused by patients’uncontrolled motions during 3D-OCT/OCTA scanning,especially in ophthalmic applications.The motion artifacts result in the low quality of OCT images and erroneous demonstration of 3D structures.Furthermore,motion artifacts can cause misdiagnosis of ophthalmic diseases and hinder studies on ophthalmic diseases that rely on OCT imaging.Some approaches have been proposed for correcting the motion artifacts in 3D-OCT scanning of the fundus.However,there is little research on motion artifact correction in 3D-OCT imaging for anterior segments.Therefore,the motion artifact correction for 3D-OCT scanning of anterior segments is of great significance.We propose an artifact correction method for high-quality 3D-OCT and OCTA imaging of anterior segments based on the inherent structures of the anterior segment.Methods Due to the short spacing between adjacent B-scans during 3D-OCT/OCTA scanning,we assume that the structural information of adjacent B-scans is almost the same and the artifacts are caused by the drifts between adjacent B-scans.Therefore,the motion artifacts in 3D-OCT/OCTA can be corrected by aligning the adjacent B-scans.Fig.2 presents the proposed motion estimation method for estimating the target’s motion during three-dimensional scanning.The key idea of the method is calculating the relative shift between adjacent B-scans by cross-correlation algorithms along the slow-scanning direction.For comparison,we introduce two other motion estimation methods—method 1 and method 2,with both metho

关 键 词：医用光学 光学相干层析成像 光学相干层析血管成像 眼前节 运动伪影 互相关 

分 类 号：O439[机械工程—光学工程]