Analysis of retinal microvasculature features in amblyopic eyes: A meta-analysis.

PURPOSE: This meta-analysis aimed to evaluate retinal vessel density (VD) in amblyopic patients using optical coherence tomography angiography (OCTA). METHODS: PubMed, Web of Science, Embase, and Cochrane Library databases were systematically searched for published articles comparing retinal microvasculature characteristics in patients with amblyopia and controls. Continuous variable outcomes were assessed using the mean difference (MD) with a 95% confidence interval. Review Manager Version 5.30 was used for the analysis. RESULTS: Thirteen qualified articles were pooled in this meta-analysis. Compared with controls, the foveal whole enface VD of superficial (SCP) and deep capillary plexus (DCP) of patients as measured by 3×3-mm scans were significantly lower in amblyopia eyes (MD: -1.37, P = 0.0003; MD: 1.70, P < 0.00001, respectively). Similarly, in the 6×6-mm scans, foveal whole enface VD of the SCP and DCP were remarkably lower in amblyopia eyes than in controls (MD: -2.24, P = 0.03; MD: -5.08, P = 0.04, respectively). The parafoveal VD of SCP in 3×3-mm scans (MD: -1.96, P < 0.00001) was also lower in amblyopic patients than in controls. Similarly, in 6×6-mm scans, amblyopia eyes showed a significant decrease, and a trending decrease in the parafoveal VD of the SCP (MD: -3.85, P = 0.007) and DCP (MD: -3.03, P = 0.10), respectively. For whole radial peripapillary capillary (RPC), VD was significantly reduced in amblyopic patients compared to controls (MD = -0.83, P < 0.00001). In addition, the deep foveal avascular zone (FAZ) was larger in amblyopic eyes than in the controls (MD = 0.55, P= 0.007). CONCLUSIONS: Our data suggest that whole foveal and parafoveal VD and RPC whole VD were reduced in patients with amblyopia. Moreover, our results reveal that the FAZ is larger in amblyopic patients. Consequently, OCTA may have the potential for diagnosing and monitoring patients with amblyopia.

Retinal microvascular and neuronal function in patients with multiple sclerosis: 2-year follow-up.

OBJECTIVE: To determine the longitudinal changes in retinal microstructure, microvasculature, microcirculation, and axonal and neuronal functions in patients with relapsing-remitting multiple sclerosis (RRMS) over the time course of about two years. METHODS: A total of 30 patients (60 eyes) with RRMS were followed for a period of 27 ± 6 months and evaluated with a battery of clinical tests including low contrast letter acuity (LCLA), intraretinal layer thicknesses by optical coherence tomography (OCT), ganglion cell function by steady-state pattern electroretinography (PERG), axonal function by polarization-sensitive OCT, volumetric vessel density (VVD) by OCT angiography, and retinal tissue perfusion (RTP) by retinal function imager. RESULTS: Axonal function measured as retinal nerve fiber layer birefringence in the temporal quadrant and vessel density in the deep vascular plexus were significantly decreased at 2-year follow-up (P < 0.05). Subgroup analyses showed that the increased retinal blood flow volume occurred in patients with no evidence of disease activity (NEDA), and with stable or improved visual function (P < 0.05). There was no significant difference in the expanded disability state scale, LCLA, RTP, VVD, or PERG measures between the two visits (P > 0.05). CONCLUSION: To our best knowledge, this is the first 2-year prospective comprehensive study with a detailed assessment of retinal microstructure and neuronal functions in patients with RRMS. The recovery of retinal microcirculation occurred in patients with NEDA, and stable or improved visual function, suggesting these measurements as potential imaging biomarkers for monitoring disease progression.

Vascular Abnormalities in Peripapillary and Macular Regions of Behcet's Uveitis Patients Evaluated by Optical Coherence Tomography Angiography.

Purpose: To investigate the involvement of peripapillary zone vascular abnormalities in Behcet's uveitis (BU) and associated visual dysfunction. We evaluated the retinal and choroidal microvascular features in both macular and peripapillary areas of BU patients to identify vascular abnormalities contributing to reduced best-corrected visual acuity (BCVA) using optical coherence tomography angiography (OCTA). Methods: A prospective, observational study was conducted in 24 eyes of 13 patients with BU and 24 eyes of 15 healthy participants as controls. They received a standard eye examination and were recorded by OCTA measurements of macular and peripapillary areas. The vascular densities of superficial capillary plexus (SCP) and deep capillary plexus (DCP), choroidal flow area, radial peripapillary capillary network (RPCN) density, foveal avascular zone (FAZ) area and perimeter, full retinal thickness (FRT), and peripapillary retinal nerve fiber layer thickness (pRNFLT) were measured.Correlations among microvascular, structural, and functional changes were assessed. Results: Our findings uncovered that the vascular density was significantly reduced in the peripapillary zone of BU eyes compared to healthy eyes, especially in the inferior subfield of the RPCN. The vascular densities of SCP and DCP quadrants within the macular zone had no significant difference between BU and control groups except for DCP density of the nasal parafoveal quadrant. Both FAZ area and perimeter were greater but without statistical significance in the BU group. Compared to healthy eyes, the choriocapillaris flow area was smaller while the FRT and pRNFLT were greater in the BU group. Notably, there was a significant correlation between the reduction in RPCN vascular density and decreased BCVA in BU patients. Conclusion: Based on OCTA, vascular changes associated with BU are more prominent in the peripapillary zone than those in the macular zone. The vascular density of the RPCN could serve as a sensitive indicator to monitoring BU pathogenic progression and treatment response using a non-invasively method of OCTA.

Longitudinal Microvascular Changes on Optical Coherence Tomographic Angiography after Macula-Off Rhegmatogenous Retinal Detachment Repair Surgery.

PURPOSE: To investigate longitudinal changes and associated factors for microvascular parameters in macula-off rhegmatogenous retinal detachment (RRD) after repair surgery. METHODS: This is a retrospective study of 34 eyes with macula-off RRD. The foveal avascular zone (FAZ) area and parafoveal vessel density were recorded every 3 months for 1 year after surgery. We analyzed 3 × 3 mm and 6 × 6 mm swept-source optical coherence tomographic (OCT) angiography images to quantify microvascular parameters. Individual clinical factors and pre- and postoperative OCT images were analyzed to find factors associated with changes in the FAZ area and vessel density 12 months after surgery. RESULTS: The differences in FAZ area and vessel density between the operated and fellow eye at 3, 6, 9, and 12 months postoperatively were 0.127 ± 0.05, 0.111 ± 0.06, 0.108 ± 0.07, and 0.105 ± 0.06 mm2 and 4.33 ± 1.42, 3.56 ± 2.05, 2.73 ± 1.72, and 2.61 ± 1.71/mm. Preoperative sensory retina thickness and surgical methods significantly correlated with decreased vessel density at 12 months. Surgical method-based analysis found that postoperative vessel density damage in the pars plana vitrectomy (PPV) group was more prominent than in the buckling group. CONCLUSION: After macula-off RRD surgery, microvascular parameters were impaired after successful anatomical repair but recovered over 12 months. The PPV group exhibited significantly lower postoperative parafoveal vessel density than the buckling group.