Aging patients have macular degeneration that leads to poor vision. The sharpness of their eyesight depends on the central macular region. A 1 mm diameter zone is crucial for ascertaining the patient’s visual acuity. This study delves into the long-term consequences of geographic atrophy and central sparing in the eyes.
The researchers initiated an age-related eye disease study. They selected 210 eyes and manually segmented GA involving the 1 mm diameter zone. The mean follow-up for the study was fixed at 3.8 years. They measured the zone’s residual area first. The study calculated the central residual effective radius or CRER by taking the square root of the residual area/ π. The residual size over time was modeled using linear mixed-effects. The GA’s different durations were accounted for by adding a horizontal translation factor to every data set.
The central residual area’s decline rate is associated with a baseline. But this relationship got eliminated after a transformation from the central area to CRER. The horizontal factor addition to data sets led to a linear CRER decline over 13 years. The total GA’s effective radius was 3.7 fold higher than CRER’s decline rate. Advanced age-related macular degeneration had a 53.3% higher CRER decline rate compared to eyes without this aging problem.
The eyes’ CRER with GA declined linearly over 13 years, approximately. Future clinical trials can consider it as the anatomical endpoint.
Ref: https://bjo.bmj.com/content/early/2020/12/23/bjophthalmol-2020-317636
