Objective: To examine the phenomenon of a prolonged choroidal filling phase (PCFP) as seen on fluorescein and indocyanine green (ICG) angiography in patients with early age-related macular disease (AMD).
Methods: One hundred eyes of consecutive patients with early AMD were studied. Patchy and slow choroidal filling in early fluorescein and distinct areas of reduced choroidal fluorescence in ICG angiography were interpreted as PCFP. In addition, associated drusen characteristics and the AMD status of the fellow eye were recorded.
Results: A PCFP was observed in 26% of eyes using fluorescein and 32% of eyes using ICG angiography, with good concordance between findings using both techniques (K = 0.9). A PCFP was associated with confluent drusen (P = .01), the presence of focal retinal pigment epithelial-atrophic patches in the study eye (P=.005), and geographic atrophy in the fellow eye (P=.03). Other drusen characteristics and the distribution of visual acuity (P = .90) were not different between eyes with and without PCFP.
Conclusions: A PCFP on fluorescein and ICG angiography is a common feature in early AMD. This sign has been interpreted as indicating reduced choroidal perfusion caused by change in diffusional characteristics of Bruch membrane. A PCFP is a clinical marker for diffuse deposits in Bruch membrane and a risk factor for the development of geographic atrophy.