Used to study eyes with advanced age-related macular degeneration, AO identified cone-like structures within areas of geographic atrophy (GA) and normal appearing cones in areas overlying drusen.
“Cone density in the GA area was calculated to be similar to that of surrounding normal-appearing retina, suggesting there may be potentially recoverable photoreceptor cells within small GA lesions,” Dr. Chung said.
Imaging with AOSLO in an eye with macular telangiectasia showed no cones within the central area of the lesion, whereas cones in the periphery appeared healthy. The technology also was used to evaluate changes in a phase 1 clinical trial where fellow eyes were randomized to receive the ciliary neurotrophic factor (CNTF)-secreting intravitreal device (NT-501 Encapsulated Cell Therapy, Neurotech) or no treatment.
Analyses of serial images taken during 24 months of follow-up in one patient showed cone densities declined by about 25% in the untreated eye but only 13% in the eye injected with the CNTF implant.
“The difference in the magnitude of the decrease was statistically significant,” Dr. Chung said. “A benefit for treatment was not detected in the analysis of other endpoints, which included visual acuity, OCT, and microperimetry. These data show the potential benefit for using AO to assess outcomes in clinical trials.”