Comparison of retinochoroidal and optic nerve head microvascular circulation between HIV-positive patients and healthy subjects using optical coherence tomography angiography.

PURPOSE: To evaluate the retinal, choroidal, and optic disc head microvascular circulation in human immunodeficiency virus (HIV)-infected individuals without retinopathy receiving highly active antiretroviral therapy (HAART) using swept-source optical coherence tomography angiography (SS-OCTA). METHODS: This cross-sectional study included 100 eyes of 100 patients with HIV infection but no HIV-related ocular disease and 108 eyes of 108 age- and sex-matched healthy subjects as the control group. SS-OCTA was used to assess foveal avascular zone (FAZ) area, retinal nerve fiber layer thickness (RNFL), choriocapillaris (CC) flow area, outer retinal (OR) thickness, radial peripapillary capillary (RPC) vessel density (VD), ONH VD, and choroidal thickness. RESULTS: No statistically significant difference was found between the two groups except in the foveal VD of the deep capillary plexus (DCP). The foveal VD of the DCP was lower in the HIV-positive group (P=0.011). The mean FAZ area (mm2), perimeter (mm), and CC flow area (mm) values were higher in the HIV-positive group at statistically significant levels (P=0.021, P=0.02, and P=0.039, respectively). However, no statistically significant differences were found between the two groups concerning the OR flow area, subfoveal choroidal thickness, or the VDs of the RPC or ONH. CONCLUSIONS: This is the first study in the literature to evaluate the microvascular circulation of the ONH in HIV-positive patients. Although retinal and choroidal microvascular circulation decreased in HIV-positive patients receiving HAART treatment, we found no effect on the microvascular circulation of the ONH or RPC microvascular circulation. Our findings suggest that retinochoroidal microvascular circulation is affected in HIV-positive patients over time.

Evaluations of the radial peripapillary, macular and choriocapillaris microvasculature using optical coherence tomography angiography in patients with systemic sclerosis.

PURPOSE: To analyze the macular microvascular (MMV) architecture, radial peripapillary capillary (RPC) network and choriocapillaris using optical coherence tomography angiography (OCT-A) in patients with systemic sclerosis (SSc) without systemic comorbidities. METHODS: The vessel densities (VDs) of the MMV, foveal avascular zone (FAZ) parameters, choriocapillaris flow areas (CCFAs), RPC VDs, and optic nerve head (ONH) parameters were measured by OCT-A. Retinal thickness and subfoveal choroidal thickness (SFCT) were measured by spectral-domain optical coherence tomography (SD-OCT). The SD-OCT and OCT-A measurements of 53 eyes of 30 SSc patients were compared with 61 eyes of 33 healthy controls. RESULTS: In the MMV analysis, a decrease in the VDs of the superficial capillary plexus and an increase in the FAZ area, FAZ perimeter and non-flow area were detected in the SSc group compared to the controls (P=0.007, P=0.001, P=0.029, P=0.018, and P=0.039, respectively). While there was a decrease in SFCT, no change was found in CCFA (P=0.001 and P=0.902, respectively). The RPC analysis revealed a decrease in the VDs of all vessels for the entire area and the intradisc area, as well as the VDs of the small vessels for the intradisc area (P=0.021, P=0.001, and P=0.003, respectively). In the ONH analysis, there was an increase in the C/D area ratios and cup volumes, and a decrease in the rim areas and nasal quadrant retinal nerve fiber layer thickness (P=0.004, P=0.004, P=0.013, and P=0.032, respectively). CONCLUSION: Decreases in RPC and MMV VDs and changes in ONH parameters were found in OCT-A measurements in patients with SSc.

Change in retinal and choroidal microvascular structures after rhegmatogenous retinal detachment surgery and effects on visual recovery.

PURPOSE: To investigate changes in retinal and choroidal microvascular structures in the macular region after surgery for rhegmatogenous retinal detachment (RRD) and their relationship to visual function at 3months. METHODS: This prospective, cross-sectional study included 37 eyes of 37 patients who underwent surgery for RRD (pneumatic retinopexy and/or pars plana vitrectomy). All patients underwent a comprehensive ophthalmologic examination, including measurement of best-corrected visual acuity (BCVA, logMAR), anterior segment and fundus examination, and optical coherence tomography angiography (OCTA) imaging 3months postoperatively. The healthy fellow eyes formed the control group. OCTA was used for the assessment of macular vessel density (VD), foveal avascular zone (FAZ), central macular thickness, and choroidal and outer retinal flow rates. RESULTS: The findings showed that the VD of the superficial and deep capillary plexuses were lower in the RRD group compared to the control group (P=0.012; P<0.001). The FAZ was larger in the RRD group (P=0.035). The choroidal flows in the 1 and 3mm2 were lower in the RRD group (P<0.001). Superficial FAZ area and choroidal flow rate (1 and 3mm2 areas) were moderately negatively correlated with BCVA (P=0.008; P=0.035; P=0.008). CONCLUSIONS: Our study demonstrated that the FAZ was larger, and the choroidal flow rate was lower, in the RRD group compared to the control group. Choroidal flow rate was negatively correlated with postoperative BCVA. Ischemic events resulting from the RRD were likely the reason for these changes.