Analysis of pre-operative factors affecting range of optimal vaulting after implantation of 12.6-mm V4c implantable collamer lens in myopic eyes

Abstract

BackgroundTo evaluate clinical factors affecting postoperative vaulting in eyes that had achieved optimal vaulting within the range of 250–750 μm following implantation of 12.6-mm V4c implantable collamer lenses (ICL).MethodsA total of 236 eyes of 236 patients that had achieved optimal vaulting following implantation of a 12.6-mm V4c ICL were retrospectively analyzed. Associations between postoperative vaulting and age, preoperative anterior chamber depth (ACD), preoperative axial length (AL), preoperative white-to-white diameter, preoperative pupil size, preoperative sulcus-to-sulcus diameter, and preoperative manifest refraction spherical equivalent were investigated using simple regression, stepwise multiple regression, and multinomial logistic regression analyses.ResultsMean central vaulting at the 6-month follow-up was 519.0 ± 112.8 μm. Variables relevant to postoperative vaulting were, in order of influence, preoperative ACD (β = 0.305, p < 0.001), preoperative pupil size (β = 0.218, p < 0.001), and preoperative AL (β = 0.171, p = 0.006). Low preoperative pupil size was associated with low optimal vaulting (250 to 450 μm), relative to that observed in the mid optimal vaulting group (451 to 550 μm) (odds ratio = 0.532, P = 0.021). Increasing preoperative ACD was associated with high optimal vaulting (551 and 750 μm), relative to that observed the mid optimal vaulting group (odds ratio = 6.340, P = 0.034).ConclusionsMyopic eyes with greater preoperative ACD, larger pupil size, and longer AL are predisposed to higher postoperative vaulting following 12.6-mm V4c ICL implantation. Therefore, the extremes of these parameters should be considered when choosing V4c ICL size.

​Short-term changes in and preoperative factors affecting vaulting after posterior chamber phakic Implantable Collamer Lens implantation

“…According to our results, neither WTW measured by any instrument nor ACD was a reliable predictor of postoperative vaulting, which was also the consensus of many similar studies [34,35,42]. Lee et al [19] obtained the following regression formula after multivariate linear regression analysis of 236 patients with 12.6-mm crystal implantation: central vault (µm) = − 0.784 + (0.171 × preoperative ACD) + (0.038 × preoperative pupil size) + (0.017 × preoperative AL). Unfortunately, the tting degree of this formula was very low (R 2 = 0.144), only one size of ICL was included in this study, and the axial direction of ICL placement was not considered, which would affect the results.…”

“…In addition, previous studies have shown that changes in pupil size were associated with postoperative vaulting [27][28][29][30]. Lee et al [19] believed that pupil constriction creates anteroposterior vectors through iris constriction, which exerts pressure on the ICL. Because the V4C ICL has a central hole, pressure equilibrium is quickly achieved between the front and rear surfaces of the ICL, facilitating this process (the fountain effect of "aquaport").…”

Correlation between vaulting intraoperative and postoperative of EVO implantable Collamer lens: a retrospective study of real-time observations of vaulting using the RESCAN 700 system

“…The two eyes with low vaulting were not reoperated, but closer follow-up was performed. The low vaulting observed in two eyes might be due to the smaller pupil diameters, as shown by a previous study [45].…”

<p>Inter-Eye Vault Differences of Implantable Collamer Lens Measured Using Anterior Segment Optical Coherence Tomography</p>

“…Also, absolute pupil ΔE were correlated with absolute vault ΔE, to investigate whether vault differences could be related to inter-eye differences in postoperative pupil sizes. The absolute vault ΔE were compared to three vault groups (average RE and LE), low vault <250 µm, intermediate/optimal [250; 750] µm and high vault >750 µm 12 and for the three lens sizes (12.6, 13.2 and 13.7) mm using the Kruskal–Wallis test. Statistical analysis was performed using IBM SPSS Statistics V23.0.…”

“…7 – 11 Despite the variety of associations put forward, the ability of explaining the vault preoperatively is limited to approximately 40% 9 , 10 and decreases to 14% if the prediction is restricted to an optimal vault range. 12 Several arguments have been presented to justify the limited predictability of the models. Lee et al have argued that the vault may depend on the dampening ability of the ciliary-sulcus complex.…”