Long-term follow-up evaluatıon of functıonal and anatomıcal changes of the retina in patients with wet age-related macular degeneration

Objective: To evaluate the changes in the retinal layers by segmentation analysis in patients with wet age-related macular degeneration (AMD) that underwent anti-VEGF treatment for 1-year follow-up period.Material and Methods: Thirty-seven eyes of 37 patients with wet-AMD naive to the treatment were included in this prospective interventional study. The patients were treated with standard of care. Treatment protocol was initial 3 monthly loading injections and then PRN regimen (as needed). Mean follow-up was 13 months. Baseline best-corrected visual acuity (BCVA), fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) was obtained. Segmentation of each retinal layer in central 1 mm and 1-3 mm area was calculated by segmentation software.Patients underwent OCT and BCVA evaluation at each visit. Data at months 3, 6 and 12 were compared to baseline values. Results: Total 33 patients out of 37 patients with wet type age related macular degeneration completed the study.The mean number of injections was 9.8. The mean logMAR BCVA was 0.60±0.28 (47.3±22.05 letters) at baseline, 0.45±0,30 (59.0±22.5 letter) at month 3, 0.41±0,33 (60,1±19,90 letter) at month 6 and 0.40±0,23 (60,7±19,80 letter) at month 12. There was significant increase in BCVA at month 3, 6 and 12 (p:0.001, p:0.001, p:0.001) compared to the baseline BCVA. Central macular thickness at baseline, month 3, 6 and 12 was 390.25±149.6-μm, 365.62±168.1-μm, 366.66±160.36–μm, and 312,74±118,4-μm respectively.No significant change in RNFL was observed in central 1 mm area and parafoveal 1-3 mm area.A statistically significant thinning in GCL at month 12 when compared to baseline (23.93±13.73-μm to 19.50±9.50-μm in 1 mm area and 44.5±12.6–μm to 39.6 ± 10.6-μm in parafoveal 1-3 mm area) was observed (p:0.001 and p:0.005). A statistically significant thinning in IPL at month 12 when compared to baseline (28.90 ± 14.36–μm to 22.35 ± 6.23 –μm in 1 mm area and 39.34 ± 8,53 –μm to 35.58 ± 7.93 in parafoveal 1-3 mm area ) was observed (p : 0.001 and p: 0.004). A statistically significant thinning in INL at month 6 when compared to baseline (34.80 ± 15,33–μm to 27.60 ± 12.59 –μm in 1 mm area) was observed (p = 0.013).No significant change in OPL and ONL was observed in central 1 mm area and parafoveal 1-3 mm area. A statistically significant thinning in RPE at month 3 when compared to baseline (39.12 ± 22.33 -μm to 29.70 ± 22.05 -μm in 1 mm area and 31.27 ± 13.11 -μm to 24.40 ± 9.99-μm in parafoveal 1-3 mm area) was observed (p ˂0,001 and p = 0.001). A statistically significant thinning in IRL at month 12 when compared to baseline (222.93 ± 93.09 -μm to 180 ± 53 -μm in 1 mm area and 255.06 ± 42.74 –μm to 240.25±40.37 -μm in parafoveal 1-3 mm area from ILM to ELM ) was observed (p: 0.001, p: 0.003). A statistically significant thinning in ORL at month 3 when compared to baseline (128.32 ± 26.92 -μm to 115.54 ± 43.98 -μm in 1 mm area and 103.81 ± 16.73 -μm to 96.38 ± 16.22 -μm in parafoveal 1-3 mm area from ELM to BM) was observed (p: 0.011 p: 0,014).Conclusion: An anatomical improvement has been observed with intravitreal ranibizumab therapy in patients with wet-AMD. These improvements seem to be occurring due to thinning in both the inner layers (GCL, IPL) and outer layers (RPE).