Abstract
Purpose :
Age-related macular degeneration (AMD) is the leading cause of vision loss in patients over 50 years of age. Drusen formation is a characteristic of non-exudative AMD. The presence of vascularized pigment epithelial detachments in the absence of exudation has previously been documented on OCT angiography (OCTA) as well as on indocyanine green angiography. The presence of vascularized drusen has also been briefly studied using Optical Coherence Tomography (OCT) and indocyanine green angiography (ICG), but the challenge of using invasive imaging in asymptomatic patients curtails detailed studies looking at this. In our study, we used OCTA to investigate the incidence and characteristics of vascularized drusen using a prospectively acquired cohort of 128 patients with intermediate non-exudative AMD.
Methods :
128 patients with intermediate non-exudative AMD in the study eye, marked by the presence of ten or more intermediate sized drusen (≥ 63 and <125 μm), 1 or more large drusen (≥125 μm), and/or retinal pigmentary changes, and exudative AMD in the fellow eye were included in the study. All patients were imaged on a commercially available SD-OCT angiography system, with both the 3x3 and 6x6 fields of view. FA and fundus photographs were also obtained on these patients.
Results :
16 instances of vascularized drusen identified on OCTA were isolated in 11 patients, representing 8.6% of the studied population. Vascularized drusen had varied appearance on OCT, with some demonstrating uniform sub-RPE hyperreflectivity (9/16), and some exhibiting multilaminar sub-RPE hyperreflectivity (7/16). In every case, FA images failed to clearly identify the neovascular nature of vascularized drusen.
Conclusions :
Vascularized drusen was identified in 8.6% of the patients in our cohort of 128 patients with intermediate non-exudative AMD using SD-OCT angiography. FA was not helpful as an imaging modality in identifying vascularized drusen. Further studies are required to elaborate on progression of such lesions.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.