Inner retinal layers' alterations and microvasculature changes after vitrectomy for rhegmatogenous retinal detachment

Purpose To examine the retinal layers' changes and alterations in retinal microvasculature in patients with rhegmatogenous retinal detachment (RRD) treated with pars plana vitrectomy (PPV). Methods Participants in this study were 103 patients with RRD, 85 macula off and 18 macula on, who were treated with PPV and gas tamponade without internal limiting membrane peeling, in two centers. All participants underwent best corrected visual acuity measurement, slit-lamp examination, fundoscopy, spectral domain-optical coherence tomography and optical coherence tomography angiography at week 5 and at month 6 postoperatively. The fellow untreated eyes were also examined and served as control data. Results A statistically significant enlargement in foveal avascular zone (FAZ) in both superficial capillary plexus (SCP) and deep capillary plexus (DCP) was noticed 5 weeks postoperatively in patients with RRD treated with PPV compared to the fellow eyes and remained 6 months after surgery. The FAZ enlargement in the operated eyes was accompanied with a statistically significant thinning of the inner retinal layer. In addition, there was a significant decrease in foveal and parafoveal vessel density (VD) in both SCP and DCP in the operated eyes compared to control eyes at week 5 postoperatively, which also remained at postoperative month 6. Conclusions The study demonstrated that patients with RRD treated with PPV presented changes in the retinal microvasculature in both SCP and DCP, including enlargement of FAZ and decrease in VD. These changes seemed to be associated with inner retinal layer thinning.