ABSTRACT
PURPOSE: To assess the clinical efficacy of sequential intrastromal corneal ring segment (ICRS) implantation and corneal crosslinking (CXL) in corneal ectasia.METHODS: To assess the clinical efficacy of sequential intrastromal corneal ring segment (ICRS) implantation and corneal crosslinking (CXL) in corneal ectasia.RESULTS: Greater improvement in uncorrected visual acuity was observed in the ICRS + CXL group than in the ICRS or CXL alone groups at both 6 (p = 0.008) and 12 months (p = 0.028). Refractive errors of sphere and spherical equivalent were significantly reduced in both the ICRS (p = 0.002 at 6 months, p = 0.004 at 12 months) and ICRS + CXL groups (p < 0.001 at both 6 and 12 months). Keratometric values including the maximum, minimum, and average were significantly reduced in all 3 groups at postoperative 6 and 12 months; however, the greatest reductions were observed in the ICRS + CXL group (all p < 0.001).CONCLUSIONS: ICRS implantation followed by CXL within 1 month seems to be effective, and may be superior to ICRS or CXL alone in improving visual acuity and reducing refractive errors and keratometric values.
Subject(s)
Collagen , Cornea , Dilatation, Pathologic , Keratoconus , Refractive Errors , Treatment Outcome , Visual AcuityABSTRACT
PURPOSE: To evaluate the clinical results of intrastromal ring segment (Keraring(R)) implantation using a femtosecond laser in patients with keratectasia. METHODS: Twenty eyes of 19 keratectatic patients (15 eyes of keratoconus and five eyes of post-LASIK keratectasia) who completed at least three months of postoperative follow-up were included in this study. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), spherical equivalent, keratometric value, corneal astigmatism, corneal higher order aberrations (HOA) and specular microscopy were determined or performed before and after surgery. In addition, intraoperative and postoperative adverse complications were recorded. RESULTS: UCVA improved in 13 out of 20 eyes (65%), and BSCVA improved in 16 out of 20 eyes (80%). At the postoperative examination there was no statistically significant reduction in the spherical equivalent with that observed at the examination before implantation. Conversely, there were statistically significant reductions in topographic mean K value and Sim K astigmatism, corneal total and coma-like HOA (p<0.05). On specular microscopy, there was no statistically significant difference between preoperative and postoperative endothelial cell density. There was one case of partial Descemet membrane detachment and one case of microperforation as a complication during surgery, which recovered over time without any treatment. CONCLUSION: Keraring(R) implantation appears to be an effective and safe procedure for improving visual acuity and stabilizing corneal refractive power in keratectactic patients.