AIM: To compare subfoveal choroidal thickness(SFCT)between cases with non-neovascular age-related macular degeneration(AMD)and neovascular AMD by optical coherence tomography(OCT)and to evaluate the contribution of choroidal thickness(CT)measurements to the understanding of pathogenesis of neovascularization in AMD.

METHODS: Fourty-eigth eyes of 24 patients who had neovascular AMD in one eye and non-neovascular AMD in the other eye were included in this retrospective, cross- sectional study as study group. Forty eyes of healthy,age and axial length matched individuals were selected as the control group. Eyes with drusen and/or pigmentary changes were included in the non-neovascular AMD subgroup. Eyes with subretinal or intraretinal fluid and/orlipid exudation due to the choroidal neovascularization were included in the neovascular AMD subgroup. OCT measurements were performed with RTVue 100-2(V 5.1, Optovue, Fremont, CA, USA)perpendicularly from the outer part of the hyperreflective line(retinal pigment epithelial layer)to the line corresponding to the choroido- scleral junction. Choroidal thickness was measured at 7 different points, 500μm intervals up to 1500μm temporal and nasal to the fovea in the study group and compared statistically between subgroups.

RESULTS: The mean age of patients was 72.4±8.97(60- 82)y. The mean age of healthy individuals was 71.2±8.8(58-81)y. Mean SFCT of neovascular AMD group were significantly thicker than non-neovascular AMD group(P<0.05). In non-neovascular AMD group, there was no statistically significant difference between the mean SFCT and the mean temporal-nasal choroid thickness(P>0.05). In neovascular AMD group, there was a statistically significant difference between the mean SFCT and the mean temporal-nasal choroid thickness(P<0.05).

CONCLUSION: Choroidal thickness measurements with OCT device can make a contribution to the understanding the phatophysiology of AMD and large prospective studies should be conducted to understand why SFCT was thicker in neovascular AMD.