Interobserver agreement for the detection of optical coherence tomography features of neovascular age-related macular degeneration.

PURPOSE To investigate the interobserver agreement for the detection of optical coherence tomography (OCT) features of disease activity in patients with neovascular age-related macular degeneration (nAMD). METHODS This was a cross-sectional agreement study in which grading of OCT line scans from patients with nAMD was conducted by two retinal specialists before the patients received treatment. Scans were graded for the presence of features of nAMD disease activity (intraretinal cysts [IRC], subretinal fluid [SRF], diffuse retinal edema [DRE], retinal pigment epithelial detachment [PED], and subretinal tissue [SRT]). RESULTS Although scans from 78 patients were available for analysis, five patients were excluded because of a mean signal strength of <7. Two hundred seventy-eight line scans were analyzed from 73 patients (40 with cross-hair scan sets and 33 with radial line scan sets). Agreement for per line scan analysis was 77% for IRC (kappa = 0.41), 81% for SRF (kappa = 0.62), 91% for macular fluid (kappa = 0.28), 79% for DRE (kappa = 0.10), 90% for PED (kappa = 0.78), and 79% for SRT (kappa = 0.53). Both observers disagreed regarding the presence of macular fluid in one patient (with a cross-hair scan). CONCLUSIONS Interpretation of OCT line scans from patients with nAMD is subject to interobserver variability. However, when all line scans acquired are examined for the presence of fluid (IRC or SRF), there is a high level of agreement for the detection of macular fluid on a per patient basis.