Comparison of retinal layer thickness measurements obtained using two different swept-source optical coherence tomography imaging modes.

PURPOSE: To compare the retinal layer thickness values obtained using two swept-source optical coherence tomography (OCT) wide modes. METHODS: This study included fifty-four healthy eyes. Three-dimensional (3D) wide and 12 radial wide OCT scans were performed in each eye on the same day. Full retinal, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GC-IPL) thicknesses with fully automated segmentation obtained in 3D wide mode, and with semi-automated correction and fully automated segmentation obtained in 12 radial wide scan. RESULTS: The intraclass correlation coefficients for full retinal thickness measurements obtained by the two protocols with fully automated segmentation were from 0.958 to 0.996, 0.754-0.918 for GC-IPL thickness measurements, and 0.013-0.727 for RNFL thickness measurements, in the nine ETDRS subfields. CONCLUSIONS: The full retinal thickness measurements determined using both fully automated segmentation algorithms were reliable and clinically acceptable. However, segmentation errors are shown when using the 12 radial wide scanning protocol with fully automated segmentation for measurement of RNFL and GC-IPL thickness.

Retinal and Choroidal Changes after Anti Vascular Endothelial Growth Factor Therapy for Neovascular Age-related Macular Degeneration.

OBJECTIVE: To investigate changes in retinal nerve fiber layer, ganglion cell-inner plexiform layer, and choroidal thickness in the macular area in patients with neovascular age-related macular degeneration who received repeated intravitreal ranibizumab and aflibercept treatments. METHODS: This retrospective study included 90 eyes of 90 treatment-naive patients. Fifty eyes were treated with intravitreal injections of aflibercept, and 40 were treated with intravitreal injections of ranibizumab. Unaffected fellow eyes (71 eyes) were used as controls. The dosage was one injection per month for 3 consecutive months as an initial treatment. The patients were examined monthly for 6 months following the initial injection. Additional intravitreal injections were given reactively in an optical coherence tomography-guided "pro re nata" protocol. Measurements of the retinal nerve fiber layer, ganglion cell-inner plexiform layer, full retina, and choroidal thickness were simultaneously obtained via swept-source optical coherence tomography in the nine Early Treatment Diabetic Retinopathy Study subfields. RESULTS: The retinal nerve fiber layer thickness in the nine Early Treatment Diabetic Retinopathy Study subfields did not differ significantly among the three study groups (aflibercept vs. ranibizumab vs. control). The ganglion cell-inner plexiform layer thickness was significantly reduced in the aflibercept group, while the choroidal thickness was reduced in both the aflibercept and ranibizumab groups. CONCLUSION: Excessive long-term vascular endothelial growth factor inhibition by an anti-vascular endothelial growth factor agent that is trapped by neuronal and retinal pigment epithelium cells may adversely affect the function of physiological vascular endothelial growth factor and harm retinal cells and vessels.

Superficial foveal avascular zone area changes before and after idiopathic epiretinal membrane surgery.

To investigate the foveal morphological changes and foveal avascular zone (FAZ) area before and after epiretinal membrane (ERM) surgery. Twenty-two eyes with treatment-naive ERM were included in this retrospective study. The central foveal thickness (CFT) and FAZ area were measured via swept-source optical coherence tomography (SS-OCT) and OCT angiography pre- and postoperatively. The unaffected fellow eyes were used as controls. The preoperative superficial FAZ area was significantly smaller in patients (0.08±0.04 mm2) than in controls (0.33±0.09 mm2; P<0.001). The postoperative superficial FAZ (0.12±0.06 mm2) area was significantly greater than the preoperative area (P<0.001). The preoperative superficial FAZ area was strongly negatively correlated with CFT (P<0.001, rho=-0.763). ERM induced significant foveal morphological changes and reduction of the superficial FAZ area. Foveal thickness was restored and FAZ area increased postoperatively. However, the process is rather slow and the recovery is incomplete.

Foveal Avascular Zone Area Changes Analyzed Using OCT Angiography after Successful Rhegmatogenous Retinal Detachment Repair.

PURPOSE: To investigate foveal avascular zone (FAZ) area after surgery in patients with rhegmatogenous retinal detachment (RRD) that involved or uninvolved the macula, and to evaluate the correlation between FAZ area and visual outcomes using swept-source optical coherence tomography angiography (OCTA). MATERIALS AND METHODS: This retrospective case-control study included 34 eyes (34 patients) with recent onset RRD that were successfully repaired with a single, uncomplicated surgical procedure (pars plana vitrectomy with gas tamponade). The changes of FAZ area were examined by OCTA after surgery. The unaffected fellow eye was used as a control for additional comparison. RESULTS: Both superficial and deep FAZ area were significantly larger in the macula-off group (superficial: 0.374 ± 0.112, deep: 0.702 ± 0.193 mm2) than in the macula-on group (superficial: 0.282 ± 0.105, deep: 0.543 ± 0.114 mm2) following surgery. The deep FAZ area was also markedly larger in the macula-off group than in the control group (0.532 ± 0.124 mm2). Correlation analyses revealed that both superficial (ρ = 0.555, P = 0.015) and deep FAZ (ρ = 0.616, P = 0.005) areas were negatively correlated with postoperative best-corrected visual acuity in the macula-off RRD group. CONCLUSIONS: The FAZ area enlargement after successful surgical repair in macula-off RRD eyes may indicate that there is an ischemic damage to retinal capillary plexus in fovea.