Intraoperative OCT versus Scheimpflug and Swept-Source OCT measurements for anterior eye parameters. J Cataract Refract Surg 2021;Abstract.
PURPOSE: To compare agreement of anterior segment parameter measurements using an intraoperative optical coherence tomography (iOCT) of a femtosecond laser (LenSx) during interface docking to the eye to preoperative Scheimpflug-tomography (Pentacam AXL) and swept-source optical coherence tomography (IOL Master 700). SETTING: Department of Ophthalmology, Goethe University, Frankfurt, Germany. DESIGN: Retrospective study. METHODS: Ninty-five eyes of 66 patients who had planned OCT-guided femtosecond laser-assisted lens surgery were included. Anterior segment measurements were performed in mydriasis prior to surgery using Scheimpflug-tomography and swept-source optical coherence tomography. After surgery iOCT images were analysed using a modification of the FIJI image processing program. Outcome measures included external anterior chamber depth (ACD), central corneal thickness (CCT) and central lens thickness (LT). RESULTS: The ACD measured with the iOCT was -0.011±0.126mm smaller (p=0.389) than with theswept-source OCT and -0.059±0.185mm than with the Scheimpflug-tomography (p=0.003). The swept-source OCT measures a -0.047±0.146mm smaller ACD than the Scheimpflug-tomography (p=0.002). The measurements of CCT using the iOCT and the Scheimpflug-tomography (-0.705±20.837μm, p=0.742) and the LT measurements of swept-source OCT and iOCT (-0.050±0.089mm, p<0.001) show no clinically relevant difference. Just the ACD between the iOCT and the Scheimpflug-tomography shows a clinically relevant difference. CONCLUSION: The comparison of the anterior segment parameters of intraoperative optical coherence tomography with swept-source optical coherence tomography showed no clinically relevant differences regarding the ACD and the lens thickness. However, Scheimpflug-tomography versus intraoperative optical coherence tomography measures a small clinically relevant difference for ACD.