Abstract
Purpose: :
Currently, the rate of conversion to advanced age related macular degeneration (AMD) is considered as the outcome measure for most clinical trials on prevention of AMD. The aim of this project was to quantify the changes in drusen volume over 12 months in eyes with AREDS grade 3 age related maculopathy to assess the natural history of drusen of more than or equal to 125µm. using a new algorithm.
Methods: :
The change in drusen volume of contralateral eyes of 15 patients treated with Ranibizumab for neovascular age related macular degeneration (AMD) were compared to the changes in drusen volume in eyes with bilateral drusen over a time course of 12 months. We created a new algorithm using NIH’s image J to measure drusen volume. We marked out drusen as elevations of RPE on SD OCT slides and compared it against the autoflorescent pictures. Only those drusens which were seen on both autoflorescence and SD OCT were measured. Using automated calculation on image J, we measured the area of individual drusen and multiplied it with individual slide spacing. Overall drusen volume was tabulated and compared.
Results: :
The % change of drusen volume at 12 months in eyes with bilateral drusen was 46.4% while the fellow eyes of ranibizumab treated eyes showed less change in drusen volume ( 37.2% , p=0.06). The change in drusen volume did not correlate to the number of ranibizumab injections in the other eye.
Conclusions: :
The fellow eye of ranibizumab treated eyes had less increase in drusen volume compared to eyes with bilateral drusen probably highlighting the potent anti-inflammatory properties of this drug even in minute concentrations. So further studies are necessary to validate this algorithm as an outcome measure for new trials on prevention of AMD.
Keywords: age-related macular degeneration • clinical research methodology