Abstract
Purpose: :
To determine the prevalence, progression, and factors related to progression of retinal pigment epithelial (RPE) atrophy as evidenced by autofluorescence abnormalities in eyes with choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD).
Methods: :
This is a retrospective analysis of consecutive patients with CNV secondary to AMD. Confluent hypoautofluorescence was defined as an area of absent autofluorescence in the macula originating from the level of the RPE, greater than or equal to 0.5 mm in greatest diameter. All images were evaluated by 2 masked readers with open adjudication if there were measurement differences of 15% or more.
Results: :
There were 188 eyes of 130 patients, who had a mean age of 83 years (standard deviation [±] 7.7), 85 (65.4%) were female. Of these follow-up imaging was available for 138 eyes (73.4%) covering a mean period of 33 ± 20 months. Mean logMAR visual acuity was 0.586 (approximate Snellen equivalent 20/77) at baseline and 0.657 (approximate Snellen equivalent 20/91) at last follow-up. Confluent hypoautofluorescence at baseline was present in 118 eyes (62.8%) and the mean area was 2.6 mm2. Visual acuity at baseline was correlated with the area of confluent hypoautofluorescence (P<.001). Among eyes with confluent hypoautofluorescence at baseline, the mean change in area over the follow-up period was 2.47 mm2, imputing an expansion rate of 0.93 mm2 per year. The factors significantly correlated with expansion rate were the area of confluent atrophy at baseline (P<0.0001) and the follow-up interval (P=0.008). An additional 23 eyes (55.3% of the remaining eyes in the follow-up group) developed confluenthypoautofluorescence over the follow-up period. The visual acuity at final follow-up was correlated with the area of confluent hypoautofluorescence (P<.001) at that time. The change in visual acuity over the follow-up period was correlated to the change in area of the confluent hypoautofluorescence (P=.015).
Conclusions: :
This study shows confluent autofluorescence is common in eyes with CNV secondary to AMD and appears be related to visual morbidity for patients with CNV secondary to AMD. This is the first study to document the prevalence, rate of progression, and factors correlated with progression of RPE atrophy in eyes with CNV. Application of strategies to limit expansion of atrophy may be as applicable in eyes with CNV as in eyes without.
Keywords: retinal pigment epithelium • age-related macular degeneration • imaging/image analysis: clinical