Purpose:
Outer retinal tubulation on spectral domain OCT has been proposed as photoreceptor rearrangement secondary to retinal insult in an array of retinal diseases, the most prevalent of which is age-related macular degeneration. This study aims to examine OCT imaging of neovascular AMD patients to compare the ORT occurrence in patients after long-term anti-VEGF therapy compared to those with treatment naïve patients.
Methods:
100 patients with exudative AMD were retrospectively evaluated for outer retinal tubulations using a custom SD Spectralis OCT high speed 49 scan line 20 by 20 degree macular thickness cube with 9x image averaging. Group one consisted of 50 patients with recalcitrant neovascular AMD enrolled in the Phase I-II open label superdose anti-VEGF (SAVE) trial. The average disease duration was 3.01 years with a treatment history of 26.4 anti-VEGF injections. Imaging was analyzed at the screening visit before the onset of the high dose (2.0mg) ranibizumab treatment regimen. Group two was composed of imaging of treatment naïve patients with no prior treatment for neovascular AMD prior to instituting therapy.
Results:
Demographic data between study groups were comparable with Group one consisting of 22 men and 28 females with an average age of 75.9 years while Group two contained 19 men and 32 women with an average age of 78.6 years. A total of 6 patients in Group one (Recalcitrant) were identified with ORT on SD-OCT imaging (12% n=50) while none of the patients in Group one (Naïve) had detectible ORT (0% n=50); (p< 0.01).
Conclusions:
Patients with recalcitrant neovascular AMD appear to exhibit a significantly elevated incidence of outer retinal tubulation as opposed to treatment naïve patients. Whether this represents an effect from anti-VEGF therapy or an indication of chronicity of CNVM is unknown.
Keywords: age-related macular degeneration • photoreceptors • retina: distal (photoreceptors, horizontal cells, bipolar cells)