In patients with dry AMD, the primary utility of OCTA is in identifying eyes that are phenotypically dry but that have underlying nonexudative neovascular disease. OCTA has clinical utility in both the dry and wet forms of AMD. 5 Severe vision loss in advanced AMD is associated with two conditions: geographic atrophy (GA) and macular neovascularization (MNV). OCTA IN AMDĪMD is the leading cause of vision loss in developed countries. In Part Two of this two-part series we will examine its usefulness for other retinal and choroidal vascular diseases. In this report, we outline the clinical utility of OCTA in exudative and nonexudative AMD. Additionally, SS-OCTA has less sensitivity roll-off with depth, and it typically uses a longer wavelength these characteristics allow better visualization through opacities and visualization of deeper structures. An advantage of SS-OCTA over SD-OCTA is its faster scanning speed, which makes possible larger scan areas and denser scan patterns with comparable acquisition times. Two forms of OCTA are in use: spectral-domain (SD) and swept-source (SS) OCTA. Segmented B-scans with flow overlay corresponding with each en face image are shown on the right (D-F). OCTA en face projections of full retinal depth (A), superficial retinal slab (B), and deep retinal slab (C), acquired in a healthy individual. 1 These characteristics have quickly led OCTA to become vital in the evaluation of patients with several chorioretinal pathologies.įigure 1. Because of the depth resolution, individual vascular layers can be visualized independently. The high resolution allows visualization of the microvasculature in much greater detail compared with dye-based angiography, potentially in a quantitative manner. 1,2Īs a derivative of OCT, this new modality also delivers high-resolution, depth-resolved images (Figure 1), which is an advantage over fluorescein angiography (FA) and indocyanine green angiography (ICGA). Because the only change between successive OCT scans of the same retinal location should be due to the movement of blood through the vessels, OCTA software generates a map of the vasculature in the back of the eye.

OCTA images are obtained by decorrelating successive OCT B-scans acquired in the same area. It uses motion contrast to visualize retinal and choroidal vasculature without the use of extrinsic dyes. OCT angiography (OCTA) is a new, rapid, noninvasive imaging modality.

Amd detection utility