Abstract
Purpose:
to evaluate the status of choriocapillaris and choroidal structures using angio-OCT in patients affected by macular atrophy secondary to age-related macular degeneration (GA) and Stargardt disease (STGDT).
Methods:
Retrospective study. All the patients underwent a complete ophthalmological examination including blue and green autofluorescence (B-FAF, G-FAF), fluorescein (FA) and indocyanine green (ICGA) angiography, enhanced depth imaging spectral domain optical coherence tomography (SD-EDI OCT) (HRA+OCT Spectralis, Heidelberg Engineering, Heidelberg, Germany) and angio-OCT using AngloVue technologies (Optovue, in).
Results:
20 eyes of 10 patients affected by GA and 20 eyes of 10 patients affected by STGDT were included in the study. Mean age was 53,3 for STGDT patients and 76,88 for GA. Atrophy was hypofluorescent in both B-FAF and G-FAF in all the cases. In the early frames FA displayed hyperfluorescence in the atrophic area in 80% of GA and 0% of STGDT patients whereas dark choroid was present in 0% of patients and 90% respectively. ICGA showed, in late frames, hypocyanescence in 95% of STGTD and 16% of GA patients and isocyanescence in 84% of GA patients. At Angio-OCT imaging it was possible to detect a global rarefaction of choroidal layers in 94% of GA patients with no selective loss of choriocapillaris while in STGDT patients loss of choriocapillaris was typically antecedent to the loss of the other layers.
Conclusions:
SSADA analysis in STGDT patients displayed a selective involvement of choriocapillaris compared to GA population. This finding results in agreement with possible expression of ABCA4 at this level and with previous ICGA studies.