Purpose:
To investigate a potential relationship between clinical parameters and final visual outcome in eyes with neovascular age-related macular degeneration (NVAMD) treated with intravitreal injections of Avastin or Lucentis over 48 weeks.
Methods:
From a database of AMD cases at our institution we retrospectively selected all eyes with NVAMD that were treated with anti-VEGF injections. All patients were treatment naïve and received intravitreal injections of either Lucentis or Avastin at the clinicians discretion. Medical charts were reviewed for every follow-up until 48 weeks after the initial injection, and demographics as well as data from the ophthalmic examination were collected and transcribed into a digital database. Statistical analyses were performed to explore a relationship between final visual acuity (VA) and: VA at baseline (BSL), 4, 12 and 24 weeks, number of injections during follow-up, first or second eye affected, lens status, and demographic parameters (age, gender).
Results:
49 eyes were included in the analysis. 12 eyes showed an improvement in VA of 3 lines or more during the 48 week follow-up, 6 of which as early as 4 weeks after the initial injection. 10 of 49 eyes lost at least one line in VA from BSL to week 48. Interestingly, there was no statistically significant difference in BSL-VA, age, or number of injections during follow-up between eyes that lost vision and eyes that remained stable or gained vision. After backward elimination, the multivariate regression model to predict VA at week 48 yielded VA at week 4 and week 24 as significant parameters (R2 = 0.77, p< 0.001). Univariate regression models with the same dependent variable showed a significant predictive power of VA (p<0.001) at BSL (R2 = 0.46), 4 weeks (R2 = 0.64), 12 weeks (R2 = 0.74) and 24 weeks (R2 = 0.74), while the absolute change in VA was not predictive of final outcome.
Conclusions:
The visual acuity within the first 24 weeks after primary intravitreal injection was reflective of the functional results at 48 weeks, while demographic and treatment factors did not seem to play a significant role.
Keywords: age-related macular degeneration