Comparison of intraoperative vs postoperative optical coherence tomography measurement of implantable collamer lens vaulting.

PURPOSE: To compare intraoperative vs postoperative optical coherence tomography (OCT) measurements of implantable collamer lens (ICL) vaulting. SETTING: American University of Beirut Medical Center, Beirut, Lebanon. DESIGN: Prospective observational cohort study. METHODS: Patients with myopia or myopic astigmatism undergoing ICL insertion in which intraoperative OCT measurements were obtained were included. Exclusion criteria included coexisting ocular problems and previous ocular surgery. The outcome measures were ICL vaulting as determined by OCT intraoperatively and postoperatively at 1 day, 1 week, 1 month, and 3 months. RESULTS: Forty-five eyes of 26 patients were included. Mean age was 27.23 ± 6.47 years (range 17 to 48 years), and mean manifest refraction spherical equivalent was -10.20 ± 3.92 diopters (D) (range -20.50 to -4.50 D). Mean ICL vaulting measured 731 ± 215 μm intraoperatively, 648 ± 219 μm at 1 day, 640 ± 204 μm at 1 week, 628 ± 212 μm at 1 month, and 632 ± 210 μm at 3 months postoperatively (P = .0009, with all postoperative vaulting measurements statistically similar to each other, but significantly different from the intraoperative measurement). However, intraoperative ICL vaulting had high predictability of postoperative vaulting at 3 months with r = 0.81 (P < .0001), and Bland-Altman analysis demonstrates a relatively constant difference between the 2 measurements as plotted against their mean with a bias of 98.27 μm and tight 95% limits of agreement range. CONCLUSIONS: Intraoperative ICL vaulting measured by OCT correlated highly with postoperative OCT vaulting and can be considered a reliable tool to predict the final ICL vault.