Purpose. To compare the intraoperative OCT (optical coherence tomographer) of the femtosecond laser LenSx (Alcon Pharma GmbH, Freiburg) with a Scheimpflug-tomographer and an anterior segment OCT and thus to investigate a possible influence on the anterior segment of the eye when docking the patient’s interface. Material and Methods. A prospective cross-sectional study was conducted with 57 subjects who underwent a planned femtosecond laser-assisted cataract surgery or refractive lens exchange. The eye to be operated on was measured prior to the operation in mydriasis with the Visante OCT (Carl Zeiss Meditec AG, Jena) and the Pentacam AXL (Oculus Optikgeräte GmbH, Wetzlar). During the surgery, images of the anterior segment of the eye were taken by the integrated intraoperative OCT of the laser, which were evaluated afterwards and compared to the values of the other devices. The parameters examined were the internal anterior chamber depth (ACD), nasal and temporal chamber angles, central corneal thickness (CCT) and central lens thickness (LT). Results. The comparison of the intraoperative OCT and the two other devices showed clinically relevant differences in all parameters. The intraoperative OCT showed a 9.19 ± 27.55 μm larger CCT, 0.96 mm (median difference) larger LT, 0.05 mm smaller ACD than the Pentacam AXL and a 21.36 ± 25.50 μm larger CCT, 0.10 mm (median difference) smaller ACD than the Visante OCT. Conclusion. The comparison of the intraoperative OCT with the Visante OCT and the Pentacam AXL shows clinically relevant differences. Changes in the anterior segment of the eye may be due to errors in measurement or docking of the patient’s interface. Keywords. femtosecond laser, OCT, anterior segment of the eye, cataract surgery, refractive lens exchange
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