Optical Coherence Tomography Guided Corneal Surgeries

Abstract

Optical Coherence Tomography (OCT)is an optical signal acquisition and processing method. It captures micrometerresolution, three-dimensional images from within optical scattering media (e.g., biological tissue). The first report of OCT imaging of corneal and anterior segment was published in 1994.FD-OCT is faster than TD-OCT, and is also much more efficient: It achieves higher speed, better resolution without losing signal-to-noise ratio.In corneal imaging Fourier domain OCT is preferred. Optical coherence tomography especially the spectral domain type with its higher speed and better resolution can map the corneal thickness. The mapping scan pattern is called “Pachymetry”. The repeatability of the pachymetry map is excellent. Optical coherence tomography pachymetry maps accurately detected the characteristic abnormal corneal thinning in keratoconic eyes. OCT also measures anterior and posterior corneal curvature, thus improves the sensitivity of keratoconus detection.