Outer retinal cysts in age-related macular degeneration

Purpose: To describe novel cystic structures ('outer retinal cysts' or ORC) found in the outer retina in age-related macular degeneration (AMD). Methods: One hundred and seventy-three consecutive eyes of 88 AMD patients were prospectively examined with spectral domain optical coherence tomography (SD-OCT). The prevalence of ORCs was searched, and their sizes and shapes were determined. Results: SD-OCT revealed round or ovoid, intraretinal, hyporeflective cystic structures with a hyperreflective border in 60 eyes (56%) with neovascular AMD and in six eyes (21%) with atrophic AMD. These cystic structures were of different sizes and shapes. They remained stable in all the patients after a follow-up period of 6 months. Conclusions: Outer retinal cyst is a new type of cystic structure recently identified in AMD patients. ORCs should not be confused with intraretinal exudates or cystoid cavities and therefore do not require any treatment. The histopathological nature of ORC remains to be determined. Further studies are necessary to determine their true origin.