Abstract
Purpose :
Reticular pseudodrusen (RPD), a feature seen in age related macular degeneration (AMD), is considered a risk factor for progression of AMD. The long-term natural history of RPD is not well described. We aim to describe the characteristics of RPD, including progression in area and morphology using fundus autofluorescence (FAF) images of eyes with RPD, taken annually over 6 years.
Methods :
We evaluated 15 eyes with RPD (8 patients) with FAF images at baseline and each annual visit over 5 years under the Age-related Eye Disease Study 2 (AREDS2) FAF ancillary study. Each subject’s annual FAF images were registered, aligned and stacked, ensuring uniform anatomic orientation. The area of RPD was outlined at each visit, along with area of abnormal autofluorescence (both hyper and hypo autofluorescence). RPD characteristics such as location (within and outside the AREDS macular grid), topographical distribution within the retina, morphological pattern (dot, ribbon, or mixed) and presence of peripapillary RPD were also recorded at each visit. Longitudinal evaluation of FAF images across visits included qualitative assessment of annual change in RPD, categorized as an increase, decrease, or no change in RPD area and the corresponding change in abnormal AF.
Results :
At baseline, the median area of RPD was 23.52 mm2 (range 1.76, 53.88). RPD was located within and outside the AREDS grid in 93.3%, with superior distribution in 100% of eyes, followed by temporal, nasal and inferior in order of frequency. There was an increase in RPD area over 5 years in 53.3% with median change of 3.33 mm2/year (range 0.74, 7.41) and a decrease in RPD in 40% with a median regression of 0.96 mm2/year (range 0.00, 2.70). In eyes with a decrease in RPD area, there was a corresponding increase in area of abnormal AF, with RPD being replaced by hypo autofluorescence. Of the 7 eyes with dot pattern at baseline, 6 converted to ribbon by year 5, and all the eyes exhibiting ribbon morphology at baseline remained the same. Peripapillary RPD was seen in 7 eyes. Of the 12 eyes with intermediate AMD at baseline, 8 progressed to geographic atrophy.
Conclusions :
RPD is a dynamic feature seen in eyes with AMD, with both increase and decrease in area. Regression of RPD is usually associated with development of hypo autofluorescence indicating atrophic changes. RPD morphology appears to reflect a unidirectional spectrum of disease pattern, with dot evolving into ribbon morphology.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.