Background and Objectives
This pilot study sought to evaluate changes in macular function and drusen volume (DV) after selective retina therapy (SRT) in patients with intermediate age‐related macular degeneration (iAMD).
Study Design/Materials and Methods
Twenty participants with bilateral iAMD were included in this prospective interventional case series study. After titrating pulse energy by real‐time feedback‐controlled dosimetry, SRT with a wavelength of 527 nm was applied around the macula of one eye of each patient. Changes in best‐corrected visual acuity (BCVA), DV within the central 5‐mm ring (C5), and retinal sensitivity (RS) of the SRT‐treated eyes (treated eyes) and untreated fellow eyes (untreated eyes) were evaluated at baseline and then at 3, 6, 9, and 12 months after treatment using linear mixed models.
Results
The mean BCVA did not change significantly between baseline and 12 months in both treated and untreated eyes (P = 0.06, P = 0.24, respectively), whereas the BCVA increase rate was faster for treated than for untreated eyes at the 12‐month visit (–0.072 logMAR; 95% confidence interval [CI], −0.085 to −0.059 logMAR; P = 0.006). The mean cube root transformation of DV (cube root DV) within C5 in the untreated eyes increased significantly from 0.278 ± 0.115 at baseline to 0.295 ± 0.132 mm (P = 0.027) at 12 months, whereas the cube root DV change in treated eyes was not significant (P = 0.553). The rate of increase in the cube root DV was lower in treated than in untreated eyes at the 12‐month visit (−0.016 mm; 95% CI, −0.018 to −0.011 mm; P = 0.015). The mean RS was increased from 22.49 ± 2.40 dB to 24.09 ± 2.19 dB (P < 0.001) in the treated eyes, whereas the change of mean RS in the untreated eyes was not significant at the 12‐month visit (P = 0.18). The treated eyes had a higher rate of increase in RS than untreated eyes at the 12‐month visit (1.012 dB; 95% CI, 0.776–1.251 dB; P = 0.037). The RS change was significantly associated with the interaction between SRT treatment and time (P = 0.028), whereas it was not associated with cube root DV change (P = 0.106). No SRT‐related adverse effects were observed in all participants during the 1‐year follow‐up.
Conclusion
Since SRT improved the mean RS and reduced the rate of change in drusen load in the treated eyes, as compared to the untreated eyes, SRT might slow the progression of iAMD. However, further large randomized clinical trials are necessary to confirm the efficacy of SRT for iAMD. Lasers Surg. Med. © 2020 Wiley Periodicals LLC