Reproducibility of macular edema measurements using OCT 3 versus HRT II in neovascular AMD

Abstract

PURPOSE: To assess reliability of optical coherence tomography (OCT) versus Heidelberg retinal topography (HRT) to record macular alterations without fluorescein angiography in neovascular AMD. METHODS: Forty patients with predominantly classic choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD) were examined by OCT, HRT macular module and fluorescein angiography (FA) before, and 6 and 12 weeks following PDT. The changes in retinal thickness in the macular area measured by OCT in 9 fields were compared to the changes in edema index obtained by HRT in corresponding 9 fields. Results were correlated with leakage determined by FA. RESULTS: Following treatment, changes in most OCT thickness values were statistically significant at both follow-ups. In contrast, only edema indices measured by HRT II following manual adjustment showed significant differences. Variations in retinal thickness measured by OCT did not correlate with changes in edema index determined by HRT in any of the 9 fields. The presence of leakage on FA showed no correlation with foveal thickness and edema index at any visit. CONCLUSIONS: The HRT II detected fewer changes in neovascular AMD then the OCT3, and may therefore be unreliable for post treatment monitoring. Due to lack of correlation, neither OCT nor HRT is able to replace the primary evaluation of therapeutic success in neovascular AMD by FA.