Abstract
Purpose:
To analyze the prevalence of subretinal drusenoid deposits (SDD) in patients with treatment naïve newly diagnosed choroidal neovascularization (CNV) in age-related macular degeneration (AMD).
Methods:
We studied 114 consecutive patients (125 eyes) with treatment naïve CNV in AMD seen during 11 months. Multimodal imaging were reviewed for druse type (soft drusen, SDD, mixed) and type of CNV. Classification for neovascularization was based on our earlier proposed grading system incorporating multimodal imaging including fluorescein angiography (FA), spectral-domain optical coherence tomography (SD-OCT), and, where necessary, indocyanine green angiography. The following types of CNV were differentiated: Type 1 (or usually described as occult or poorly defined with FA), Type 2 (or usually described as well-defined or classic with FA), Type 3 (or retinal angiomatous proliferation (RAP)) and polypoidal choroidal vasculopathy (PCV). SDD was considered present when there was OCT evidence ≥ 5 definite drusenoid deposits above the retinal pigment epithelium (RPE) in > 1 B-scan, with consistent changes in either near-infrared imaging or the blue light channel as previously described. Soft drusen were determined from color fundus photographs and confirmed by SD-OCT.
Results:
In 30 eyes with newly diagnosed CNV without prior treatment there were too advanced exudative changes with subretinal fibrosis which made a classification impossible. In 94 eyes (mean patient age 79.4 years) type of neovascularization and druse type were graded. The types of neovascularization were type 1 for 39 eyes, type 2 for 33, type 3 for 18 and PCV for 4 eyes. SDD only without the presence of soft drusen were detected in 14 of 94 eyes (14.9%) with a treatment naïve CNV secondary to AMD. In eyes with SDD only, type 1 was identified in 0 eyes, type 2 in 13 eyes, type 3 in 1 eyes and PCV in 0 eyes.
Conclusions:
SDD represent a common phenotypic characteristic in eyes with treatment naïve CNV in AMD. The prevalence of SDD only in type 2 neovascularization was higher than for other types. The high incidence of SDD in type 2 might be explained by their location in the subretinal space. The predominant druse type either SDD or soft drusen might be relevant in the development of either sub-retinal pigment epithelium (RPE) neovessels or proliferation vessels above the RPE in the subneurosensory location.
Keywords: 688 retina •
700 retinal neovascularization •
453 choroid: neovascularization