Evaluation of intraoperative aphakic eye axial length measurements using swept-source OCT

PURPOSE Evaluation of intra-operative aphakic axial eye length (AL) measurements using swept source optical coherence tomography. SETTING Hanusch Hospital, Vienna, Austria. DESIGN Prospective single-center study. METHODS Patients scheduled for cataract surgery were measured using swept-source optical coherence tomography (ss-OCT, IOLMaster 700, Carl Zeiss Meditec AG, Jena, Germany) to assess the axial eye length. Intra-operatively, swept source optical coherence tomography (ss-OCT) measurements were performed with a prototype device (IOLMaster 700 connected to an OPMI Lumera 700 microscope, CZM) at the beginning of cataract surgery furthermore of the aphakic eye and 2 months after surgery. RESULTS Of the 59 eyes of 59 patients, the phakic median AL pre-operatively (pre-OP) and intra operatively (intra-OP) were 23.61 mm ± 0.96 (SD) and 23.51 mm ± 0.96 (SD). Absolute median difference was 0.028 ± 0.02 (SD) (p=0.049). Median phakic AL intra-OP versus 2 months post operatively (post-OP) was 23.51 mm ± 0.97 (SD) vs 23.49 mm ± 0.95 (SD). Absolute median difference was 0.049 ± 0.04 (SD) (p=0.000).Median AL intra-OP aphakic versus vs 2 months post-Op pseudophakic were 23.42 mm ± 0.97 (SD) versus 23.42 mm ± 0.97 (SD). Absolute median difference was 0.038 ± 0.04 (SD) (p=0.379). CONCLUSIONS Intra-OP swept source OCT technology of the phakic and aphakic eye shows excellent comparability to pre- and post-operative measurements. This technique allows axial eye length measurements with high precision in cases where pre-op biometric measurements are not possible.