Abstract
Purpose: :
To demonstrate the ability of Spectral Domain Optical Coherence Tomography to image geographic atrophy (GA), and to compare the size and shape of these lesions with those obtained using fundus photography and fundus autofluorescence (FAF).
Methods: :
Five eyes of patients with dry AMD were imaged using digital fundus photography, FAF, and SD-OCT. Images were registered to each other in the same coordinate system to allow for the measured area and shape to be compared across these modalities.
Results: :
Fundus photographs did not reliably determine the extent of geographic atrophy present. GA appears bright on SD-OCT compared to the surrounding areas with an intact retinal pigment epithelium (RPE) because of increased reflected light from the exposed underlying choroid. SD-OCT and FAF both identified the shape and extent of geographic atrophy reproducibly. Furthermore, measurement of the area of geographic atrophy is comparable between the two methods with a difference of approximately 3% of the total area.
Conclusions: :
SD-OCT appears to identify and allows for the reproducible quantification of GA area. The size and shape of these areas correlate well to GA visualized by FAF images; however SD-OCT imaging also provides cross-sectional information about the anatomy of the retina.
Keywords: age-related macular degeneration • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retinal pigment epithelium