Abstract
Purpose:
To evaluate the differences between pro re nata (PRN) treatment regimen and treat and extend (TE) regimen with intravitreal ranibizumab in neovascular age-related macular degeneration (AMD) regarding visual outcome, course of visual acuity (VA), frequency of injections, and frequency of visits.
Methods:
Results of 185 eyes treated in a TE regimen with intravitreal ranibizumab for neovascular AMD were analyzed in a retrospective, interventional, consecutive case series. In 142 eyes the PRN pre-treatment period was directly compared to the following TE period. Further the TE results of 43 treatment-naïve eyes were analyzed. PRN treatment was based on monthly optical coherence tomography (OCT) evaluation; retreatment was applied in case of reoccurrence of intra- or subretinal fluid or hemorrhages. In the TE regimen treatment intervals were sequentially lengthened by 2 weeks, starting at 4 weeks, until signs of exudation recurred.
Results:
The mean TE follow-up was 8.9±1.2 months (range 6-11 months). After changing from PRN to TE regimen mean Snellen VA continuously improved from 20/42 (0.47±0.22) at TE baseline to 20/36 (0.55±0.23) at 6 months follow-up. The proportion of eyes that lost any VA during TE was 1.6%. During the PRN maintenance phase (after 3 monthly loading doses) mean VA dropped from 20/36 (month 3; 0.56±0.21) to 20/42 (0.47±0.22) at last PRN follow-up (= Baseline TE). The mean difference of maximal and minimal reached VA during the follow-up period was significantly bigger for the PRN maintenance phase (0.30±0.17) than for the TE period (0.10±0.09 for PRN pretreated eyes, 0.11±0.10 all TE eyes; p=0.002). The mean number of injections/month was 0.47 (PRN) and 0.76 (TE), respectively. With the TE regimen the mean maximum period of extension without recurrence was 7.07±2.28 weeks. The number of visits attended per month was significantly higher in the PRN than in the TE period (1.10±0.10 vs. 0.76±0.17, both including baseline and exit visit, p=0.008).
Conclusions:
Eyes with neovascular AMD experienced significant better visual stabilization in the maintenance phase, but with more injections, after changing from PRN to a TE regimen. The TE treatment approach also was associated with significantly fewer patient visits compared with monthly OCT monitoring such as in the PRN regimen.
Keywords: 462 clinical (human) or epidemiologic studies: outcomes/complications •
412 age-related macular degeneration •
754 visual acuity