Shen Kai, Lu Hui, Baig Sarfaraz, Wang Michael R
Department of Electrical and Computer Engineering, University of Miami, 1251 Memorial Drive, Coral Gables, FL 33146, USA.
Department of Biomedical Engineering, University of Miami, 1251 Memorial Drive, Coral Gables, FL 33146, USA.
Biomed Opt Express. 2017 Oct 6;8(11):4887-4918. doi: 10.1364/BOE.8.004887. eCollection 2017 Nov 1.
The multi-frame superresolution technique is introduced to significantly improve the lateral resolution and image quality of spectral domain optical coherence tomography (SD-OCT). Using several sets of low resolution C-scan 3D images with lateral sub-spot-spacing shifts on different sets, the multi-frame superresolution processing of these sets at each depth layer reconstructs a higher resolution and quality lateral image. Layer by layer processing yields an overall high lateral resolution and quality 3D image. In theory, the superresolution processing including deconvolution can solve the diffraction limit, lateral scan density and background noise problems together. In experiment, the improved lateral resolution by ~3 times reaching 7.81 µm and 2.19 µm using sample arm optics of 0.015 and 0.05 numerical aperture respectively as well as doubling the image quality has been confirmed by imaging a known resolution test target. Improved lateral resolution on skin C-scan images has been demonstrated. For 3D SD-OCT imaging of human skin, fingerprint and retina layer, we used the multi-modal volume registration method to effectively estimate the lateral image shifts among different C-scans due to random minor unintended live body motion. Further processing of these images generated high lateral resolution 3D images as well as high quality B-scan images of these tissues.
引入多帧超分辨率技术以显著提高光谱域光学相干断层扫描（SD-OCT）的横向分辨率和图像质量。利用几组在不同组上具有横向子光斑间距偏移的低分辨率C扫描3D图像，在每个深度层对这些组进行多帧超分辨率处理，可重建更高分辨率和质量的横向图像。逐层处理可生成整体横向分辨率高且质量好的3D图像。理论上，包括去卷积在内的超分辨率处理可以共同解决衍射极限、横向扫描密度和背景噪声问题。在实验中，通过对已知分辨率测试目标成像，已证实使用数值孔径分别为0.015和0.05的样品臂光学器件时，横向分辨率提高了约3倍，分别达到7.81 µm和2.19 µm，并且图像质量提高了一倍。已证明在皮肤C扫描图像上横向分辨率得到了改善。对于人体皮肤、指纹和视网膜层的3D SD-OCT成像，我们使用多模态体积配准方法来有效估计由于随机微小的意外活体运动而在不同C扫描之间的横向图像偏移。对这些图像的进一步处理生成了这些组织的高横向分辨率3D图像以及高质量B扫描图像。
