Longitudinal changes in retinal microvasculature after panretinal photocoagulation in diabetic retinopathy using swept-source OCT angiography

This study evaluated quantitative changes in microvascular parameters after panretinal photocoagulation (PRP) in diabetic retinopathy (DR), using swept-source OCT Angiography (SS-OCTA). A total of 27 treatment-naïve eyes were subjected to PRP and followed-up for > 12 months after the procedure. Foveal avascular zone (FAZ) area, macular perfusion density (PD), and vessel length density (VLD) were calculated on a 3 × 3 mm en face OCTA image and nonperfusion area (NPA) was obtained on a 12 × 12 mm en face OCTA image. One month after PRP, PD and VLD of superficial and deep capillary plexus decreased and subsequently, increased progressively across the next 12 months, with statistically significant differences (P = 0.015 and 0.02). Continuous decreasing trends in total NPA values was observed across 12 months after PRP (P = 0.125). A difference in PD of the superficial capillary plexus between baseline and 6 months post PRP, was significantly associated with the progression of DR, 12 months after PRP (OR 0.528; P = 0.025). We found significant longitudinal retinal microvascular changes after PRP in DR. Overall macular perfusion status was impaired and progressively recovered across the next 12 months, compared to the baseline. Additionally, the early treatment responses in PD can predict the long-term outcomes of PDR after PRP.

Swept source OCT-Angiography assessing a case of aneurysmal type 1 neovascularization secondary to high-myopic posterior staphyloma

Aim: To report an uncommon case of aneurysmal type 1 neovascularization (polypoidal choroidal vasculopathy) secondary to high-myopic staphyloma in a Caucasian patient, assessed with multimodal imaging including swept source OCT-Angiography. Methods: Observational case report Results: About 73-year-old Caucasian male patient with high myopia (axial length = 27.24 mm). Fundus examination showed a myopic conus and a deep orange-brownish nodular lesion at the edge of a deep haemorrhage and connected to a large choroidal vessel. ICGA showed a circular hyperfluorescent lesion in mid-phase, without any branching vascular network. OCT-Angiography could detect the aneurysmal lesion non-invasively as a small circular high-flow lesion in the outer retina slab, with a shadowing in the choriocapillaris slab. At the level of the aneurysmal lesion, structural OCT showed a high bilobed PED, without any subretinal fluid. A vascular flow was noted within the PED on cross-sectional OCT-A, confirming the vascular aneurysmal nature of this lesion. Additionally, swept source OCT highlighted the presence of an abrupt change in choroidal thickness, from 62 µm in the peripapillary area to 120 µm underneath the polypoidal lesion, with dilated choroidal vessels. Conclusion: To our knowledge, this is the first report of OCT-A findings in aneurysmal (polypoidal) dilation secondary to high-myopic staphyloma. We could demonstrate the usefulness of OCT-A detecting non-invasively the aneurysmal dilation and the usefulness of swept source OCT assessing the choroidal structure to better understand the pathophysiology of this uncommon finding.