Implantable collamer lenses after intracorneal ring segments for keratoconus

To report the clinical characteristics and visual outcomes of patients with keratoconus treated with posterior chamber phakic intraocular lenses after implantation of intracorneal ring segments (ICRS). This retrospective study included 11 eyes of eight patients diagnosed with keratoconus treated with ICRS and posterior chamber phakic intraocular lenses. The preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), preoperative and postoperative keratometric data, manifest refraction and spherical equivalent were recorded. No complications were observed. At 38.18 ± 18.7 months of follow-up, the mean spherical error was -0.06 ± 0.46 D (+0.75 to -0.75 D) and cylindrical error of -1.22 ± 0.65 D (-0.25 to -1.5 D). The preoperative spherical equivalent was -10.52 ± 5.88 D (-3.12 to -22.75 D) and the postoperative spherical equivalent was -0.68 ± 0.45 D (0 to -1.25 D), p < 0.001. The preoperative and postoperative UDVA were 1.31 ± 0.37 logMAR (mean 20/400 Snellen, 0.69-1.77 logMAR) and 0.14 ± 0.04 (mean 20/30 Snellen, 0.09-0.47 logMAR), with a p value <0.001. The preoperative and postoperative CDVA were 0.289 ± 0.14 logMAR (mean 20/40 Snellen, 0-0.477 logMAR) and 0.16 ± 0.08 (mean 20/25 Snellen, 0.09-0.39 logMAR), with a p value of 0.007. Combined treatment of keratoconus with ICRS and posterior chamber phakic intraocular lenses was a safe and effective procedure for high refractive errors induced by keratoconus in these selected patients.