Wen Yajing, Jiang Dan, Tang Kexin, Chen Wei
School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China.
Graefes Arch Clin Exp Ophthalmol. 2023 Oct;261(10):2729-2741. doi: 10.1007/s00417-023-05997-3. Epub 2023 Mar 2.
Optical coherence tomography (OCT) is a revolutionary in vivo imaging technology that presents real-time information on ocular structures. Angiography based on OCT, known as optical coherence tomography angiography (OCTA), is a noninvasive and time-saving technique originally utilized for visualizing retinal vasculature. As devices and built-in systems have evolved, high-resolution images with depth-resolved analysis have assisted ophthalmologists in accurately localizing pathology and monitoring disease progression. With the aforementioned advantages, application of OCTA has extended from the posterior to anterior segment. This nascent adaptation showed good delineation of the vasculature in the cornea, conjunctiva, sclera, and iris. Thus, neovascularization of the avascular cornea and hyperemia or ischemic changes involving the conjunctiva, sclera, and iris has become prospective applications for AS-OCTA. Although traditional dye-based angiography is regarded as the gold standard in demonstrating vasculature in the anterior segment, AS-OCTA is expected to be a comparable but more patient-friendly alternative. In its initial stage, AS-OCTA has exhibited great potential in pathology diagnosis, therapeutic evaluation, presurgical planning, and prognosis assessments in anterior segment disorders. In this review of AS-OCTA, we aim to summarize scanning protocols, relevant parameters, and clinical applications as well as limitations and future directions. We are sanguine about its wide application in the future with the development of technology and refinement in built-in systems.
光学相干断层扫描（OCT）是一种革命性的体内成像技术，可呈现眼部结构的实时信息。基于OCT的血管造影术，即光学相干断层扫描血管造影（OCTA），是一种非侵入性且节省时间的技术，最初用于可视化视网膜血管系统。随着设备和内置系统的不断发展，具有深度分辨分析功能的高分辨率图像已帮助眼科医生准确地定位病变并监测疾病进展。凭借上述优势，OCTA的应用已从眼后段扩展到眼前段。这种新的应用在角膜、结膜、巩膜和虹膜的血管系统显示方面表现良好。因此，无血管角膜的新生血管形成以及涉及结膜、巩膜和虹膜的充血或缺血性改变已成为眼前段光学相干断层扫描血管造影（AS-OCTA）的潜在应用。尽管传统的基于染料的血管造影术被认为是显示眼前段血管系统的金标准，但AS-OCTA有望成为一种可比但对患者更友好的替代方法。在其初始阶段，AS-OCTA在眼前段疾病的病理诊断、治疗评估、术前规划和预后评估中已展现出巨大潜力。在这篇关于AS-OCTA的综述中，我们旨在总结扫描方案、相关参数、临床应用以及局限性和未来方向。随着技术的发展和内置系统的完善，我们对其未来的广泛应用充满信心。
