Long-term changes in retinal layers in patients undergoing intravitreal ranibizumab for neovascular age-related macular degeneration : Retinal layers after anti-VEGF therapy

Impact of Intra-Retinal Fluids on Changes in Retinal Ganglion Cell and Nerve Fiber Layers in Neovascular AMD under Anti-VEGF Therapy

Purpose: To investigate the influence of intraretinal fluid (IRF) on change in retinal nerve fiber layer (RNFL) and retinal ganglion cell layer (RGCL) and thickness in patients with naive neovascular AMD under anti-VEGF treatment. Design: post hoc analysis. Methods: 97 eyes of 83 patients on continuous therapy with intravitreal anti-vascular endothelial growth factors (anti-VEGF) and a follow-up of 24 months were included. RGCL and RNFL thickness in the perifoveal (-O), parafoveal (PF), and nasal areas and number of injections (IVI) were recorded before the first IVI as well as 1 and 2 years after initiating treatment and compared longitudinally and between groups with and without IRF. Results: The group with IRF at baseline had a higher RNFL thickness at baseline and showed a significant reduction in RNFL-PF between baseline and first and second follow-ups (p < 0.001) but not between first and second follow-ups. The group without IRF showed no significant reduction in RNFL over time. The presence of IRF was not associated with a reduction in RNFL-O or RNFL-nasal. RGCL thickness decreased significantly in both groups with and without IRF after 2 years. Number of IVIs showed no significant correlation to RNFL or RGCL after stratification for the presence of IRF. Conclusions: The presence of IRF has a significant influence on RNFL thickness at baseline as well as on its changes over time during anti-VEGF therapy. The preoperative presence of IRF should be considered when comparing changes in RNFL thickness after IVI.

Impact of intravitreal ranibizumab, aflibercept and bevacizumab on retinal ganglion cell and nerve fibre layer thickness in Neovascular age‐related macular degeneration

PURPOSE

To compare the effects of monotherapy with intravitreal ranibizumab, aflibercept and bevacizumab on retinal ganglion cell layer (RGCL) and retinal nerve fibre layer (RNFL) in patients with naïve neovascular age-related macular degeneration (nAMD).

METHODS

This is a retrospective cohort study with three-groups comparison. 83 patients and 97 eyes on continuous monotherapy with an intravitreal anti-vascular endothelial growth factor (anti-VEGF) were followed for 24 months and divided into three groups according to anti-VEGF (aflibercept: 25 eyes, ranibizumab: 34 eyes, bevacizumab: 38 eyes). Main outcome measures included: RGCL and RNFL thickness, best corrected visual acuity (BCVA), central macular thickness (CMT), macular volume (MV) and the presence of intraretinal fluids (IRF), subretinal fluids (SRF) and retinal pigment epithelial atrophy (RPE-atrophy). All outcome measures were recorded at the time of the first injection, 1 and 2 years after treatment and compared longitudinally and between groups.

RESULTS

The mean age was 79 ± 7 years. The RGCL thickness, MV, CMT and the presence of IRF and SRF decreased significantly within all three medication groups (p < 0.05 for all) with no significant difference between groups over the 2-year follow-up period (p > 0.10 for all). The decrease in RNFL thickness was not significant within or between the groups after a 2-year follow-up (p > 0.055 for all). RPE-atrophy increased significantly after 2 years in all three groups (p < 0.028 for all) with no significant difference between groups at all three time points (p > 0.307 for all). BCVA was comparable between the three groups over the 2-year follow-up period (p > 0.22 for all).

CONCLUSIONS

Monotherapy with intravitreal aflibercept, bevacizumab and ranibizumab was associated with comparable significant decreases in RGCL thickness, CMT, MV, IRF and SRF in naïve nAMD patients during the first 2 years of treatment. Furthermore, no significant differences either in BCVA or RNFL thickness were observed between the three intravitreal anti-VEFGs during the first 2 years of treatment.

Managing Neovascular Age-Related Macular Degeneration in Clinical Practice: Systematic Review, Meta-Analysis, and Meta-Regression

The use of anti-vascular endothelial growth factor (VEGF) agents has profoundly changed the prognosis of neovascular age-related macular degeneration (nAMD). As clinical experiences have accumulated, it has become mandatory to summarize data to give information that can be useful in everyday practice. We conducted a systematic review to identify randomized controlled trials (RCTs) and observational studies that reported 12-month changes in best-corrected visual acuity (BCVA) in patients with nAMD on anti-VEGF monotherapy. Data were analyzed in a random-effects meta-analysis with BCVA change as the primary outcome. Meta-regression was conducted to evaluate the impact of multiple covariates. Four hundred and twelve heterogeneous study populations (109,666 eyes) were included. Anti-VEGFs induced an overall improvement of +5.37 ETDRS letters at 12 months. Meta-regression showed that mean BCVA change was statistically greater for RCTs (p = 0.0032) in comparison with observational studies. Populations following a proactive regimen had better outcomes than those following a reactive treatment regimen. Mean BCVA change was greater in younger populations, with lower baseline BCVA and treated with a higher number of injections (p < 0.001). Our results confirm that anti-VEGFs may produce a significant functional improvement at 12 months in patients with nAMD.

Anatomical effects of intravitreal anti-vascular endothelial growth factor injections on inner layers of the lesion-free retina

PURPOSE

The primary aim of the study was to investigate the effects of anti-vascular endothelial growth factor (VEGF) injections on the inner retinal layer anatomy of the lesion-free retina in eyes treated for neovascular age-related macular degeneration (nAMD). The secondary aim was to compare the changes of inner retinal layers in the lesion-free region of treated eyes with the same region of the untreated, fellow eyes and, thus, to elucidate any adverse effect of anti-VEGF treatments independently of 1-year aging changes.

METHODS

This was a retrospective, longitudinal, case-control study of 50 eyes of 25 patients. Twenty-five eyes with nAMD comprised the study group (16 eyes treated with aflibercept and 9 eyes treated with ranibizumab) and 25 fellow eyes with dry AMD (16 eyes in AREDS 2 and 9 eyes in AREDS 3) comprised the fellow eye group. Spectral-domain optical coherence tomography (SD-OCT) measurements were done at pre-treatment, 1 month after three loading anti-VEGF injections and at the end of 1 year. The retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL) thicknesses and total retinal thickness in the macula were measured. Thicknesses of inner retinal layers which were lesion-free in the outer nasal subfield of ETDRS grid were analysed and the changes in thicknesses during the follow-up period were compared between study and fellow eye groups. Paired t-test for normally distributed variables was applied for analyses of differences for the comparison of the results across the pre-and the post-. A p value of less than 0.05 was considered statistically significant.

RESULTS

The mean number of injections was 5.76 ± 1.26 in the study group in 1 year. The mean decrease in total retinal thickness was significant with 6.08 ± 9.05 µm (p= 0.003) in nAMD group and was insignificant with 0.32 ± 1.03 µm (p> 0.05) in fellow eye group with dry AMD. Most of the retinal thickness decrease was during first three injections in nAMD group. Total retinal thickness and GCL thickness were thinner in the study group at every follow-up examination, but the difference between groups was not statistically significant (p> 0.05). RNFL, GCL, IPL, and INL thicknesses did not demonstrate a statistically significant change in both study and fellow eye groups during 1 year follow-up period (p> 0.05).

CONCLUSIONS

Repeated anti-VEGF injections in nAMD appear to have no significant effect on the RNFL, GCL, IPL, and INL thicknesses of the lesion-free retina. Additionally, there was no significant difference in inner retinal layer changes between in eyes treated with anti-VEGF injections for nAMD and fellow eye group during 1-year follow-up.

Dose-Response Relationship between Intravitreal Injections and Retinal Nerve Fiber Layer Thinning in Age-Related Macular Degeneration

PURPOSE

To determine if multiple intravitreal injections of vascular endothelial growth factor (VEGF) inhibitors for unilateral exudative age-related macular degeneration (eAMD) are associated with thinning of the retinal nerve fiber layer (RNFL), we compared RNFL thickness measurements from the injected eye with that of the fellow eye with nonexudative age-related macular degeneration (neAMD).

DESIGN

Retrospective, cross-sectional study.

PARTICIPANTS

Patients undergoing anti-VEGF therapy for unilateral eAMD.

METHODS

Patients receiving anti-VEGF therapy secondary to eAMD in 1 eye with neAMD in their fellow eye were identified. Patients with a known diagnosis of glaucoma were excluded. Spectral domain OCT measurements of the peripapillary RNFL thickness from both eyes were performed and compared. The differences in the RNFL thickness measurements between eyes were correlated with the number of injections and the duration of therapy.

MAIN OUTCOME MEASURES

Correlation between the number of anti-VEGF injections and peripapillary RNFL thinning.

RESULTS

A total of 108 eyes of 54 patients were evaluated in this study. The average peripapillary RNFL thickness measurements of the injected eye and fellow eye were 87.3 ± 9.6 μm and 89.0 ± 7.5 μm, respectively (P = 0.055). The RNFL thickness difference (fellow eye minus injected eye) was significantly correlated with the number of injections (r = 0.40, P = 0.002) and months of injections (r = 0.38, P = 0.005). The relationship between the difference in the RNFL thickness and the number of injections had a nonlinear dose-response relationship that became apparent after approximately 30 injections and 50 months of injections.

CONCLUSIONS

The difference in RNFL thickness measurements between injected eyes and uninjected fellow eyes was largely within the reported normal limits for interocular differences between healthy eyes. Nevertheless, there was a dose-response relationship between RNFL thinning and number of injections among patients receiving a greater number of injections, suggesting that anti-VEGF injections may have a modest effect on the RNFL thickness after several years of therapy in eyes requiring more anti-VEGF injections; however, we cannot exclude that the RNFL thinning may be secondary to active age-related macular degeneration (AMD) disease progression in both eyes.