Visual acuity loss associated with excessive "dry macula" in exudative age-related macular degeneration

Retinal sensitivity above macular neovascularization under anti-VEGF therapy in exudative neovascular age-related macular degeneration

PURPOSE

Growth of macular neovascularization (MNV) associated with development of complete retinal pigment epithelial and outer retina atrophy (cRORA) been observed in eyes neovascular age-related macular degeneration (nAMD) under effective anti-vascular endothelial growth factor (VEGF) therapy. We aimed to evaluate the influence of the presence of MNV on the sensitivity of the overlaying retina both in patients with or without cRORA and to generate hypotheses about their association.

METHODS

Pilot study on nAMD patients undergoing long-term anti-VEGF therapy that had also undergone microperimetry testing. Area of MNV and, if present, associated cRORA were identified on optical coherence tomography (OCT) volume scans and transposed onto en-face near-infrared images. Mesopic microperimetry performed at the same visit was then superimposed. Retinal sensitivity above the MNV and the surrounding retina were compared, excluding areas of cRORA.

RESULTS

Twenty-six eyes (19 f, 7 m; age 79.3 ± 5.7 y; fu 4.0 ± 1.8 y; 7.4 ± 2.5 inj./y) were classified into a no cRORA (n = 11) and a cRORA group (n = 15). In the no cRORA group, mean retinal sensitivity above the MNV did not differ from the surrounding retina (20.9 ± 2.8 vs. 22.0 ± 2.4, p = 0.33), while in the cRORA group, a lower sensitivity above the MNV in comparison to the surrounding retina was observed (16.2 ± 3.4 vs. 19.9 ± 2.0, p = 0.001).

CONCLUSION

In the absence of cRORA, retinal sensitivity above the MNV did not differ significantly from that of the surrounding retina. These results could indicate a possible nutritional function of the MNV to the overlying retina in cases where no cRORA is present.

High frequency SD-OCT follow-up leading to up to biweekly intravitreal ranibizumab treatment in neovascular age-related macular degeneration

A remarkable proportion of neovascular age-related macular degeneration (nAMD) patients respond rather poorly to ranibizumab treatment, in spite of the minimum 4-week follow-up and treatment interval. Usually, retreatments are based on nAMD activity as evaluated by Spectral-domain Optical coherence Tomography (SD-OCT), biomicroscopic fundus examination and visual acuity changes. In this prospective pilot study, we aimed to study SD-OCT changes in a high-frequent follow-up manner (weekly (month 0–6), biweekly (month 7–12)) throughout the first year, which consequently led to intravitreal ranibizumab being administered up to biweekly. Best corrected visual acuity (BCVA) was already significantly improved at week 2. Central retinal thickness (CRT), intraretinal and subretinal fluid (SRF) were significantly improved from week 1 onwards. Half of the patients showed nAMD activity at week 2 or 3 and received the first retreatment earlier than 4 weeks after baseline injection. In total, 46% of retreatments were already applied 2 or 3 weeks after the previous treatment. Greater range of CRT and SRF fluctuation during follow-up was associated with lower final BCVA. Lower baseline BCVA and better SRF improvement at week 2 was associated with greater BCVA improvement. In conclusion, high-frequency SD-OCT follow-up provided a good option for adapting treatment in nAMD individually.

Inhibition of TRAF6 alleviates choroidal neovascularization in vivo

Choroidal neovascularization (CNV) is a type of wet age-related macular degeneration (AMD) which is a major cause of blindness in elder patients. Tumor necrosis factor receptor-associated factor 6 (TRAF6) promotes tumor angiogenesis via upregulating the expression of hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF). Additionally, TRAF6 facilitates the inflammatory response in macrophages and microglia. Here, using mouse laser-induced CNV model and TRAF6 siRNA, the study shows that TRAF6 is a critical player in CNV. The expression of TRAF6, HIF-1α, and VEGF increased in the model. TFAF6 siRNA intravitreal (IVT) injection inhibited CNV formation, as well as expression of HIF-1α and VEGF, activation of macrophages and microglia. Together, our data suggest that TFAF6 inhibition reduces CNV formation via down-regulating expression of HIF-1α and VEGF and activation of macrophages and microglia, demonstrating the unique advantages of TRAF6 inhibition in the alleviation of AMD.