Impact of optic media opacities and image compression on quantitative analysis of optical coherence tomography.

PURPOSE To analyze the impact of opacities in the optical pathway and image compression of 32-bit raw data to 8-bit jpg images on quantified optical coherence tomography (OCT) image analysis. METHODS In 18 eyes of nine healthy subjects, OCT images were acquired from the central macula. To simulate opacities in the optical system, neutral-density (ND) filters with linear absorption spectra were placed between the OCT device and examined eyes. Light reflection profiles (LRPs) of images acquired with various ND filters were compared. LRPs of the 32-bit raw data were compared with those obtained from the 8-bit jpg compressed images. RESULTS ND filters induced a linear decrease of reflectivity in OCT images, depending on initial signal intensity. Quantitative OCT analysis showed no significant difference between 32-bit raw data and 8-bit jpg files (P > 0.05). CONCLUSIONS Quantitative OCT analysis is not significantly influenced by data compression. A mathematical model can correct for optical opacities to improve OCT images.