Optimising assessment intervals improves visual outcomes in ranibizumab-treated age-related neovascular degeneration: using the stability phase as a benchmark.

BACKGROUND: To observe visual acuity change in the stability phase when follow-up intervals are decreased in ranibizumab-treated neovascular age-related macular degeneration (nvAMD).
METHODS: Selection of patients was based on a review of a cohort of 189 eyes of 154 patients with nvAMD treated with intravitreal ranibizumab in routine clinical practice. Patients were transferred from a base hospital with a 8-week follow-up interval to a community eye clinic, enabling a new follow-up interval of 4 weeks. Staff, assessment, and treatment protocols were equivalent in the two centres. Patients were included when they were in the stability phase of treatment defined 1 month after having completed their three initiation treatments with ranibizumab. Each patient was required to have attended at least a further 12 visits; this means a follow-up time for a year or longer, consisting of six visits at the base hospital followed by six visits at the new eye clinic. The best-corrected visual acuity (BCVA), follow-up intervals and injection numbers were collected.
RESULTS: Seventy-two eyes of 62 patients were included. The mean follow-up interval for the six visits in the base hospital was 56.81 days, and in the new eye centre 31.81 days. The BCVA loss in the base hospital was -1.13 letters, compared to a gain of +4.61 letters in the community eye clinic over the six visits. The number of ranibizumab injections was 3.67 in the base hospital, compared with 3.91 in the other centre over the respective periods.
CONCLUSION: Visual acuity improves and severe visual loss decreases when follow-up intervals reduce from approximately 8 weeks to 4 weeks. Furthermore, using the stability phase to evaluate the outcome and effectiveness of our treatments for age-related macular degeneration appeared to be an efficient tool.