Purpose: To determine the long-term microvascular alterations associated with macular cystic changes after retinal detachment surgery with silicone oil tamponade.
Methods: The results of two optical coherence tomography angiographies performed at 11 months and 38 months after silicone removal were retrospectively analyzed for 30 eyes. The data were compared between both measurements and between eyes with macular cysts (MC+) and without macular cysts (MC-). Two patterns of cysts were identified and compared: cysts exclusively involving the inner nuclear layer (INLc) and cysts present in all retinal layers.
Results: At both end points, 20 eyes (67%) presented with macular cysts, 12 of them (40%) had INLc. At the first end point, vascular density of superficial capillary plexus was higher and superficial foveal avascular zone was smaller in MC+ eyes than in MC- eyes (P = 0.04 and P = 0.017, respectively). At the second end point, vascular density of superficial capillary plexus significantly decreased in MC+ eyes as compared with the first end point (P < 0.001) and superficial foveal avascular zone enlarged (P < 0.001). Macular central thickness decreased between follow-ups only in eyes with INLc (P < 0.01). The final best-corrected visual acuity was better in eyes with INLc than in eyes with cysts present in all retinal layers (P < 0.01). There was no difference between the final best-corrected visual acuity in eyes with INLc and MC- eyes.
Conclusion: Macular cysts are a common finding long after silicon removal. Vascular remodeling seems characterized by an initial increase of the vascular density of superficial capillary plexus in eyes with cysts, which is followed by its progressive decrease. The INLc is the most common pattern of cysts. They are associated with a progressive decrease of the central macular thickness without visual impairment.