To compare vaulting height and clinical results in patients who underwent anterior chamber phakic intraocular lens implantation with different lens diameters. Methods

Thirty-five eyes (19 patients) who underwent anterior chamber phakic intraocular lens (V4C or V5) implantation were divided into two groups according to lens diameters, which were based on the patient C or V5) implantation were dividdiameters. Group 1 was implanted with a 12.6 mm diameter lens (WTW, 11.3–11.7 mm; 22 eyes) and group 2 was implanted with a 13.2 mm diameter lens (WTW, 11.8–12.2 mm; 13 eyes). Changes in the central vault over time, refractive error, visual acuity, endothelial cell count, and complications were evaluated as clinical outcomes. Results

The post operative mean central vaulting heights at 1, 3, and 6 months Group 2 showed significantly higher vaulting at each visit (all, p < 0.05). High vaulting (greater than 750 mm) at 1, 3, and 6 months after surgery involved 27% (6 eyes), 27% (6 eyes), and 18% (4 eyes) in group 1 and 69% (9 eyes), 61% (8 eyes), and 53% (7 eyes) in group 2 ( p < 0.05), respectively. Uncorrected distance visual acuity (logMAR) and spherical equivalent were not significantly different between two groups ( p > 0.05). Conclusions

The results of optimal vaulting shows the lens diameter should be adjusted according to the surgeon's experience or nomogram when the horizontal corneal WTW diameter was used to determine lens diameter. Especially in cases using a V4C or V5 model anterior chamber phakic intraocular lens, 13.2 mm in diameter (V5) shows higher central vaulting than 12.6 mm in diameter (V4C).