Assessing the Reliability of Automated OCT Retinal Thickness Measurements in Patients with Choroidal Neovascularization Due to Age-Related Macular Degeneration

BACKGROUND AND OBJECTIVE To compare automated versus manual retinal measurement using Stratus optical coherence tomography (OCT) (Carl Zeiss Meditec, Dublin, CA) in patients with choroidal neovascularization (CNV) due to age-related macular degeneration (AMD). PATIENTS AND METHODS Patients with subfoveal CNV due to AMD underwent Stratus OCT imaging. Each scan was evaluated for automated: foveal center point thickness, central subfield thickness, signal strength, and manual: central retinal thickness, central retinal/lesion thickness, CNV thickness, pigment epithelial detachment thickness, and number of correct retinal boundaries (CRBs). RESULTS A total of 209 OCT visits (49 patients) were assessed. On fast macular thickness map, 52% of scans had less than 4 (of possible 6) CRBs placed by the automated OCT algorithm. There was a mean difference of 34 microm between automated foveal center point thickness and manual central retinal thickness (P < .00005). Only 40% and 27% of automated foveal center point thickness and central subfield, respectively, lay within +/- 25 microm of manual central retinal thickness. As the number of CRBs or signal strength increased, the difference between manual and automated measurements decreased. CONCLUSION Manual retinal thickness measurements differ significantly from those calculated by the current automated Stratus OCT software in exudative AMD.