OCT技术发展日新月异，产品不断升级，高清的OCT图像加深了眼科医生对疾病的认识，已经成为临床上眼底疾病不可或缺的诊断利器。为了帮助广大读者从多模式影像角度更全面的理解疾病，本图谱病例不但突出介绍了SS-OCT和SS-OCTA的特点和解读，还配有其他影像学资料，包括荧光血管造影、脉络膜血管造影、眼底彩照等。本图谱按不同眼底疾病分类介绍，病例丰富，所有病例均来自作者临床工作中接诊的患者，实用性强和可读性强，期望能为广大眼科医生、技师和研究生提供有益的帮助和参考。

It has been 20 years since the optical coherence tomography （OCT） imaging technology emerged as a revolutionary imaging modality that fundamentally improved the diagnosis in ophthalmology. Thanks to the continuous innovations， OCT technology has evolved from time-domain OCT， to spectral-domain OCT， and to now swept-source OCT (SS-OCT）. The third generation of OCT technology， SS-OCT， is characterized by its fast scanning speed， high sensitivity， great penetration， deep imaging depth range， and wide field of view. Currently，SS-OCT technology is still in its early stage but is evolving rapidly. Contrasty OCT structural images of high resolution have become an indispensable diagnostic tool for ophthalmic dis-eases. In recent years， another breakthrough of OCT is OCT Angiography (OCTA）， which obtains vascular images of the retina and choroid in vivo without the use of fluorescein dye or indocyanine green dye. OCTA can better reveal vascular morphology of the retina and choroid and detect early choroidal neovascularization by displaying the vascular structures on different anatomic layers. This technique is being widely used in the examination of many fundus vas-cular diseases.
　　This atlas introduces the technical principles of SS-OCT imaging， as well as OCTA strati-fication algorithm and quantification. Most of the OCT and OCTA images in this book were taken with SVision's SS-OCT， which showcases the capabilities of the latest OCT technolo-gies. With a maximum imaging depth range of 6-12 mm， it is very useful in imaging patho-logical myopia， posterior scleral staphyloma， vitreous-related diseases， and intraocular tumors.In addition， the instrument features ultrawide angle optics. OCTA images of up to 87°(129°inner angle） can be obtained in a single scan. The automatic montage is able to provide an OCTA image covering the entire posterior hemisphere of 200° (inner angles）. It serves as a noninvasive imaging modality to evaluate the severity of retinal vascular diseases such as dia-betic retinopathy and retinal vein occlusion and emerges as an invaluable alternative to inva-sive fluorescein angiography.
　　To help readers understand the disease from a multimodal imaging perspective， the cases in this atlas include not only SS-OCT and SS-OCTA， but also other imaging modalities including fundus fluorescein angiography (FFA）， indocyanine green angiography (ICGA）， and color fun-dus photography. All cases in this atlas are from the authors' clinics. This atlas is aimed at ophthalmologists， technologists， residents in ophthalmology， and researchers in hope to advance the knowledge of SS-OCT and OCTA.
　　This atlas would not have been possible without the efforts of a team of amazing residents and fellows from the Ophthalmology Department of Peking Union Medical College Hospital.We are grateful for their contribution in support of providing the cases. We would also like to express our sincere gratitude to Hongxia Chang，Yajing Ma， and Zhengming Shi for their assis-tance in image acquisition and image processing.