Purpose: To compare therapy-induced reading and distance visual acuity (dVA) increases in neovascular age-related macular degeneration (nAMD) and uveitis-associated cystoid macular edema.
Methods: This longitudinal study included 68 treatment-naive eyes: 39 subfoveal nAMD eyes with disrupted photoreceptor layers treated with monthly ranibizumab and 29 uveitis-associated cystoid macular edema eyes with intact photoreceptor layer treated with 1 triamcinolone injection. Patients were examined with high-definition optical coherence tomography, Early Treatment Diabetic Retinopathy Study dVA (logarithm of the minimum angle of resolution), reading acuity (logRADscore), and maximum reading speed (words per minute) over 3 months of therapy.
Results: In uveitis-associated cystoid macular edema, logarithm of the minimum angle of resolution and logRADscore improved 1 day post treatment, from 0.49 ± 0.28 to 0.39 ± 0.3 (P = 0.018) and 0.71 ± 0.53 to 0.56 ± 0.49 (P = 0.012), respectively. In nAMD, logarithm of the minimum angle of resolution improved 1 week after anti-vascular endothelial growth factor therapy from 0.59 ± 0.29 to 0.49 ± 0.24 (P = 0.002), with no change in logRADscore. One month after treatment, logRADscore improved from 1.09 ± 0.65 to 0.90 ± 0.60 (P = 0.002). In uveitis-associated cystoid macular edema, the recovery course of reading and dVA was comparable, and in nAMD, reading acuity recovery was delayed. Irrespective of disease, a small reduction in dVA resulted in a larger reading acuity decrease.
Conclusion: Cystoid macular edema resolution was associated with rapid synchronous reading and dVA improvement, whereas nAMD was followed by faster recovery of distance than reading acuity. In both conditions, reading acuity expressed by critical angular resolution was more suppressed by active disease and recovered relatively more than distance acuity. These discrepancies indicate that reading acuity might be a more sensitive measure for vision decrease in macular diseases than dVA. Reading acuity seems to be an important adjunct assessing intravitreal therapy efficacy.