Noncontact corneal pachymetry with lit lamp-adapted optical coherence tomography

PURPOE: The purpoe of thi tudy wa to determine the accuracy, the reproducibility, and the limit of agreement of noncontact central corneal thickne meaurement with lit lamp-adapted optical coherence tomography (OCT). DEIGN: Nonrandomized comparative clinical trial. METHOD: In a propective comparative obervational tudy, a total of 108 conecutive patient (108 eye) with normal cornea (92 eye) and different corneal alteration (16 eye) participated. ix equential meaurement of the central corneal thickne with lit lamp-adapted OCT and with ultraound (U) pachymetry at 1640 m−1 were performed. The main outcome meaure were accuracy, reproducibility aeed with preciion and coefficient of variation (CV), and limit of agreement of central corneal thickne meaurement. REULT: The mean central corneal thickne value were 541 ± 43 μm (OCT) and 549 ± 44 μm (U) with a mean preciion of ± 5.8 μm (CV 1.08%) and of ± 4.0 μm (CV 0.73%), repectively. The method comparion revealed equivalence (± 2D) in the 5% range with a mean difference between both method of 7.9 μm (1.45%). The relative error wa 8.7 μm (1.6%), which correponded to limit of agreement (± 2D) ranging from −9.5 μm to 25.3 μm. CONCLUION: Central corneal pachymetry with lit lamp-adapted OCT revealed, for clinical purpoe, an excellent accuracy and reproducibility with a high degree of agreement compared with U pachymetry. Thu, the preented OCT ytem eem to be a promiing diagnotic modality to objectively meaure corneal thickne in a convenient noncontact mode.