Figure 1. Example Scanning Laser Ophthalmoscope (SLO) image of a macular degeneration participant’s left retina.

The black dots indicate visual stimuli that the participant was able to respond to. The black triangles indicate stimuli that the participant did not respond to. The silver dot in the center indicates the likely fovea location. The silver line indicates the extent of the scotoma as drawn by the clinician and author DKD. Measurements of scotoma size were calculated on a subject-by-subject basis using each individual’s SLO image of their retina. A measurement of the diameter was made horizontally through the fovea as well as vertically through the fovea. This measurement was then converted to visual degrees using previously reported methods²⁰.