OCT Angiography in Healthy Human Subjects

Abstract

OCTA generates high-resolution, noninvasive angiograms qualitatively similar to conventional fluorescein angiography. OCTA may serve as a bridge to assess some features of the retinal microvasculature between conventionally performed angiograms.

Optical Coherence Tomography versus Fundus Fluorescein Angiography in Diagnosis of Type 2 CNV in Wet AMD

“…It is still, however, an extremely useful tool in the diagnosis of active lesions. Newer technologies, namely the OCT angiography (OCTA) which is minimally invasive and quick could be the next step forward towards quicker, non-invasive and showing accurate vascular detail [9][10][11]. Various studies have shown that OCTA shows high specificity in the diagnosis of CNV compared to FFA [12,13].…”

The Importance of VRI and AOR Segmentations in Optical Coherence Tomography Angiography

“…Using by OCTA, the vasculature and blood flow of retina and choroid can be visualized in detail through detecting motion contrast of erythrocytes in the vessel, using serial optical coherence tomography B-scans. OCTA has an ability to perform the separate segmentations including the vitreoretinal interface (VRI), the superficial retinal layer, the deep retinal layer, avascular outer retina (AOR), the choriocapillaris and the choroid (Figure 1) [1][2][3][4][5][6][7][8].…”

“…Using by OCTA, the vasculature and blood flow of retina and choroid can be visualized in detail through detecting motion contrast of erythrocytes in the vessel, using serial optical coherence tomography B-scans. OCTA has an ability to perform the separate segmentations including the vitreoretinal interface (VRI), the superficial retinal layer, the deep retinal layer, avascular outer retina (AOR), the choriocapillaris and the choroid (Figure 1) [1][2][3][4][5][6][7][8].In a healthy eye, the VRI has no vascular structure though the ganglion cell layer of the retina has the superficial retinal capillary plexus based on vitreo-retinal histology and VRI segmentation of OCTA (Figure 1, VRI) [1][2][3][4][5][6][7][8]. Preretinal neovascularization (PNV) is characterized by networks of vessels lying on the surface of the retina and invading the cortical vitreous gel and extending into the vitreous cavity.…”

“…AOR is the layer between the outer plexiform layer (OPL) in the inner border and ellipsoid zone in the outer border. The outer retina segmentation between the OPL and Bruch membrane by OCTA show no vascular blood flow in a normal eye (Figure 1, Avascular) [1][2][3][4][5][6][7][8]. Choroidal neovascularization (CNV) defines the development of the new blood vessels derived the choroid and the invasion into sub-retinal pigment epithelium (RPE) or subretinal space via a break in Bruch membrane.…”

Advances in Optical Coherence Tomography Angiography

“…OCTA is a non-invasive, non-dye-based imaging technique that employs motion contrast to create high-resolution depth-resolved angiographic images of vascular flow in a matter of minutes. [1][2][3] The software compares the decorrelation signal or phase variance between consecutive OCT B-scans acquired at the same retinal cross-section to detect motion contrast. [4][5][6] Multiple OCTA image artifacts may affect image quality.…”