![]() The role of OCTA, both en face and transverse scans, has not only been studied in the early recognition of the disease but also in monitoring the response to treatment with anti-VEGF. identified detectable flow on OCTA at the level of hyperreflective foci in nascent type 3 neovascularization followed by progression of the lesion from DCP into the RPE and sub-RPE space (active stage) or rarely regression without functional impairment. Regarding OCTA features preceding the onset of exudative type 3 MNV, Sacconi et al. characterized active type 3 MNV as high-flow tuft-shaped vessels originating from DCP, frequently associated with a small clew-like lesion in the choriocapillaris layer. En face OCTA revealed type 3 neovascular lesions originating from DCP. OCTA imaging is a valuable tool in the recognition of type 3 neovascularization not only allowing flow detection within type 3 lesions but also defining precise anatomical location. OCTA may be useful in confirming the presence of intraretinal neovascular lesion and monitoring response to anti-vascular endothelial growth factor agents. To conclude, careful evaluation of SD-OCT allows for early detection of type 3 neovascularization at a pre-exudative stage. No neovascular lesions were found on OCTA after six injections of bevacizumab. ![]() SD-OCT performed 2 months before showed the same hyperreflective lesion associated with a shallower PED. An 84-year-old female presented with hyperreflective foci in the outer retina overlying a serous pigment epithelium detachment (PED) with focal RPE disruption on SD-OCT. SD-OCT performed 2 months before showed a smaller hyperreflectivity at the same location, without intraretinal fluid. A 79-year-old male presented with a small hyperreflective density in the outer retina surrounded by scant intraretinal fluid on SD-OCT and a bright vessel on OCTA, suggesting early-stage type 3 neovascularization. SD-OCT performed 2 months before showed a smaller RPE elevation at the same location without intraretinal fluid. Optical coherence tomography angiography (OCTA) confirmed the presence of a tuft-shaped intraretinal neovascular lesion. Our results show that speckle introduces a limit to the accuracy of phase-sensitive OCT and that speckle brightness should be considered to avoid erroneous interpretation of experimental data.A 76-year-old male presented with a small hyperreflective density in the outer nuclear layer with subtle retinal pigment epithelium (RPE) elevation and few intraretinal cysts on spectral-domain optical coherence tomography (SD-OCT). Finally, we apply these new results in compression OCE to demonstrate a ten-fold improvement in strain sensitivity, and a five-fold improvement in contrast-to-noise by incorporating independent speckle realizations. Experimental measurements show an almost three-fold degradation in sensitivity between regions of high and low speckle brightness at a constant OCT SNR. We describe how the inaccuracy in speckle reduces phase difference sensitivity and introduce a new metric, speckle brightness, to quantify the amount of constructive interference at a given location in an OCT image. In this study, for the first time, we demonstrate, through theory and experiment that speckle significantly lowers the accuracy of phase-sensitive OCT in a manner not accounted for by the OCT signal-to-noise ratio (SNR). However, this approach is not representative of turbid samples, such as tissue, which exhibit speckle. In phase-sensitive OCT, motion is typically estimated using a model of the OCT signal derived from a single reflector. Phase-sensitive optical coherence tomography (OCT) is used to measure motion in a range of techniques, such as Doppler OCT and optical coherence elastography (OCE).
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