Figure 5.

Relationships between measurement errors and rotation in OCT images in eyes with nonneovascular AMD. The foveal thickness was measured in three ways; foveal thickness measured parallel to the A-scan (FTx), thickness measured perpendicular to RPE in the original stretched image (FTy), and thickness measured perpendicular to the RPE in the nonstretched/anatomically correct image (FTz). Both FTx/FTz and FTy/FTz showed an increase as the angle increased. The increase was more gradual in FTx/FTz than in FTy/FTz. The actual measurement values showed good agreement with the mathematical model imitating the same image stretching (b/a = 2) as the Cirrus HD-OCT review software.