Evolution of ETDRS visual acuity. Measures are reported for each subject. before: before SLO training; after: immediately after SLO training; three months later: three months following SLO training. Changes in ETDRS values could be considered significant when greater than 0.2 logMAR [38, 39]. Note that ETDRS visual acuity consistently increased with the SLO training and, globally, gains were retained three months later.