Evaluation of fellow eye in Turkish population of unilateral neovascular age related macular degeneratin by optical coherence tomography

The aim of this study is to study fellow eyes of unilateral neovascular AMD in the Turkish elderly population by utilizing the OCT is to detect biomarkers before neovascularization develops. 168 eyes of 168 patients with the disease were included in the study. Age, gender, smoking of all cases history, hypertension,hypercholesterolemia and family history of AMD were questioned. In addition to routine eye examination during follow-up visits, OCT and color fundus photographs were performed in all cases at each visit.By using the ETDRS automatic segmentation protocol in OCT imaging drusen volume was calculated in 3mm and 6mm areas. Intraretinal hyperreflective material (IRHF), Subretinal drusenoid in all images deposit (SDD), presence of heterogeneous reflectivity in drusen (hRF), pigment retinal epithelium detachment (PED) was evaluated. At the end of the study, 27 eyes developed neovascularization, while, 141 eyes continued as dry type. Of 168 patients, 80 (47%) were female and 88 (53%) were male, with a mean age of 75.87±10.26 (56-96). There was no difference in terms of age and gender distribution between the two groups. Baseline OCT image was obtained from all subjects at the beginning of the study. The mean follow-up period was 23.62±5.15 months. At the end of the study, 141 of 141 patients eye (study eye) (83.9%) was non-neovascular, while 27 eyes (16.1%) of 27 patients developped neovascularization. There was no evidence of geographic atrophy development in any eye during the study period. Results represnted smoking increased the risk of neovascularization 2.58 times (OR= 2.58, P=0.02). In the non-neovascular group, drusen volume ≥0.03 in 3mm and 6mm circles with the size greater than mm3 has been shown to play an important role in the progression of AMD (P<0.001, R=0.61, R=0.24 respectively). In the neovascular group, IRHF, SDD, hRF and drusen volume in 6mm circular area centered on the fovea was associated with the increased risk of disease progression. The factor providing the highest risk in this group was intraretinal hyperreflective focus (P<0.001, R=0.76). While drusen volume greater than ≥0.03 mm3 in 3mm and 6mm circles played an important role in the progression of non-neovascular AMD, drusen volume in the 3mm circular area was found to be more significantly associated with disease progression (P <0.001, R=0.61, R=0.24 respectively). In the neovascular group, IRHF, SDD, hRF, and drusen volume in a 6mm fovea-centered circular area were associated with disease progression, and the factor providing the highest risk was found to be intraretinal hyperreflective focus (P<0.001,R=0.76). Key Words: Age Related Macular Degeneration, Optic Coherence Tomography, Unilateral Neovascularization