Abstract
Purpose:
To determine the frequency of detection of neovascular age-related macular degeneration (AMD) on spectral domain optical coherence tomography (SD-OCT) low density (LD) B-scans, high density (HD) B-scans, and a single en face OCT image at the ellipsoid level in patients with neovascular AMD.
Methods:
15 participants (18 eyes) with the diagnosis of neovascular AMD were imaged with SD-OCT (Spectralis OCT, Heidelberg) acquired under LD (19 raster B-scans) and HD (145 raster B-scans) scan protocols. HD-OCT images were used to generate raw en face OCT images at the photoreceptor inner segment ellipsoid (ISe) depth.<br /> <br /> The images were read by 3 independent graders in a masked fashion for the presence of intraretinal fluid and/or subretinal fluid (SRF) in the LD and HD-OCT scans and only SRF in the en face OCT scans. The type 1 grader was a retina specialist trained in reading all three imaging modalities, the type 2 grader was a retina specialist not trained in reading en face images, and the type 3 grader was a second year resident not trained in reading any of the three imaging types.
Results:
Upon analysis of the LD-OCT, HD-OCT, and en face OCT images, neovascular activity was detected in 78%, 94%, and 89% of images (n=18) respectively by the type 1 grader, 78%, 94%, and 100% of images (n=18) by the type 2 grader, and 83%, 94%, and 72% of images (n=18) by the type 3 grader. Grader detection of neovascular activity was the same as clinician detection of neovascular activity on the date of the patient’s exam in 67%, 50%, and 56% of images (n=18) for the type 1 grader, 67%, 50%, and 44% of images (n=18) for the type 2 grader, and 61%, 50%, and 61% of images (n=18) for the type 3 grader. The type 1 grader detected SRF more often on en face OCT than LD (P<0.01) and HD-OCT (P<0.01), and the type 2 grader detected SRF more often on en face OCT than HD-OCT (P<0.05).
Conclusions:
These data suggest that HD-OCT imaging may allow more frequent detection of neovascular AMD than LD-OCT or a single en face OCT image at the ISe depth. A single en face image at the ISe retinal depth may be comparable to LD-OCT in detecting neovascular activity but is less likely to detect activity than HD-OCT. However, SRF may be more frequently detected on a single en face image at the ISe depth than on LD and HD-OCT images.