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Purpose To evaluate the capacity of OCT angiography (OCTA) for detecting infraclinical lesions in parafoveal capillaries in diabetic patients without diabetic retinopathy (DR). Methods This prospective observational cross-sectional case-control study analyzed the superficial and deep capillary plexuses (SCP and DCP) on macular OCTA scans (3 × 3 mm) centered on the fovea. We compared 22 diabetic patients (34 eyes included) without DR diagnosis on color fundus photographs, with 22 age- and gender-matched nondiabetic controls (40 eyes included). Qualitative analysis concerned morphological ischemic capillary alterations. Quantitative analysis measured foveal avascular zone (FAZ) size, parafoveal capillary density, and enlargement coefficient of FAZ between SCP and DCP. Results Neither the qualitative nor quantitative parameters were significantly different between both groups. No microaneurysms or venous tortuosity was observed in any of the analyzed images. On the SCP, the mean FAZ area was 0.322 ± 0.125 mm2 in diabetic patients and 0.285 ± 0.150 mm2 in controls, P = 0.31. On the DCP, the mean FAZ area was 0.444 ± 0.153 mm2 in cases and 0.398 ± 0.138 mm2 in controls, P = 0.20. Conclusion OCTA did not detect infraclinical qualitative or quantitative differences in parafoveal capillaries of diabetic patients without DR in comparison with nondiabetic controls.

Purpose To describe multimodal imaging of two cases of bilateral non-vascularized pigment epithelial detachments (PED) in young patients with a long-term follow-up. Methods A complete ophthalmological examination was performed at each follow-up visit including best corrected visual acuity (BCVA), intraocular pressure, slit lamp examination, spectral domain optical coherence tomography (SD-OCT), fluorescein and indocyanine green angiography, OCT angiography. Results Multimodal imaging of two women presenting avascular PED, aged 43 and 57, respectively, was described. In both patients, SD-OCT revealed a high central macular hyporeflective elevation corresponding with PED. Both patients showed a choroidal layer thicker than 420 μm. Fluorescein and indocyanine green angiography didn’t show any choroidal neovascularization either at early or late frames. Cross-sectional and en face optical coherence tomography angiography (OCTA) didn’t show any flow beneath the PED. During the follow up period one eye showed a retinal pigment epithelium tear and all eyes showed the presence of apical sub-retinal fluid and hyperreflective material on the top of the PED. None of the two patients showed any sign of atrophy during the follow-up period. Conclusion The peculiar characteristics of the presented cases suggest that specific pathogenetic mechanisms, not necessarily related to age related macular degeneration, may play a key role in the development of these lesions. Whether early onset of such drusenoid PED is a specific entity resulting from a genetic deficit of lipid transporters in the RPE is unknown. Further genetic and metabolic studies should be conducted.