Enabling Technologies for Next-Generation Ophthalmic OCT

描述(申请人提供)：自20世纪90年代初引入S以来，光学相干断层扫描(OCT)以其微米级分辨率对视网膜病变进行非侵入性成像的能力，极大地影响了眼科诊断。最新的OCT眼前段成像显示，这项技术也可能很快在角膜病理诊断、青光眼和屈光手术中得到常规应用。最近推出了两项新的光学技术，它们有望再次给眼科OCT带来革命性的变化，但目前每项技术都受到技术限制，限制了其潜在的适用性。最近引入的光谱域OCT(SDOCT)用于视网膜成像，使图像采集速度比传统的时域方法快约100倍，从而极大地改变了这一格局。重要的是，这一进展允许快速积累黄斑体积数据集，其中单个横断面图像很容易与其确切的黄斑位置相关，并且病理可以在3个维度上表征。然而，目前的SDOCT实现受到基本技术限制，将可用成像深度限制在~2 mm，图像信噪比随深度小于~1 mm而显著下降。因此，这一令人兴奋的新功能不太适合成像玻璃体异常、深层视网膜/脉络膜病变、视神经头形态或任何比眼前段角膜更深的结构。另一项可能显著影响眼科诊断学的光学创新是最近在OCT引入的分子对比成像。免疫球蛋白血管造影术是眼科的一项基本诊断技术，但由于OCT对非相干散射过程的内在不敏感性，OCT无法检测到其荧光。在这个试探性/开发性项目中，我们将实施新技术来解决这两个限制。该项目的具体目标是：1.通过实施一种新的光谱结构照明方法，扩展光谱域光学相干断层扫描(SDOCT)的可用成像深度，用于视网膜和前段成像；2.在分子对比光学相干断层扫描(MCOCT)中应用新概念，以允许实时、三维(3D)成像ICG对视网膜和脉络膜血管网络的渗透；以及3.通过工程学和临床研究人员的密切合作，在活体患者中演示这两种新技术。

DESCRIPTION (provided by applicant): Since its introduction in the early 1990's, optical coherence tomography (OCT) has strongly impacted ophthalmic diagnostics through its ability to image retinal pathologies noninvasively with micron-scale resolution. Recent demonstrations of OCT imaging in the anterior segment indicate that this technology may also soon find routine applications in diagnosis of corneal pathologies, glaucoma, and in refractive surgery. 2 new optical technologies have recently been introduced which are poised to revolutionize ophthalmic OCT yet again, however each currently suffer from technical limitations which limit their potential applicability. The recent introduction of spectral domain OCT (SDOCT) for retinal imaging has dramatically altered the landscape by allowing for ~100x faster image acquisition rates than the conventional time-domain approach. Importantly, this advance allows for rapid accumulation of volumetric macular datasets, in which individual cross-sectional images are readily correlated with their exact macular position and pathologies may be characterized in 3 dimensions. However, current implementations of SDOCT suffer from fundamental technical limitations which limit the available imaging depth to ~2mm, with significant fall-off of image signal-to-noise ratio as a function of depth below ~1mm. Thus, this exciting new capability is not well suited for imaging vitreous abnormalities, deep retinal/choroidal pathologies, optic nerve head morphology, or any structures deeper than the cornea in the anterior segment. A second optical innovation which could dramatically impact ophthalmic diagnostics is the recent introduction of molecular contrast imaging in OCT. IGG angiography is a fundamental diagnostic technique in ophthalmology, but its fluorescence is not detectable in OCT because of the inherent insensitivity of OCT to incoherent scattering processes. In this exploratory/developmental project, we will implement new technology to address both of these limitations. The specific aims of the project are to: 1. Extend the available imaging depth of spectral domain optical coherence tomography (SDOCT) for both retinal and anterior segment imaging applications by implementing a novel spectrally structured illumination approach; 2.Apply new concepts in molecular contrast optical coherence tomography (MCOCT) to allow for real-time, three-dimensional (3D)imaging of ICG infiltration of the retinal and choroidal vascular networks; and 3.Demonstrate both new techniques in living patients through close collaboration between engineering and clinical co-investigators.