Comparison of Two Different Accelerated Corneal Cross-linking Procedure Outcomes in Patients with Keratoconus

Abstract

Background: Corneal cross-linking treatment is the unique treatmentmethod that can cease the progression of keratoconus disease.Because of the long duration of conventional treatment, acceleratedcross-linking treatment methods are being developed.Aims: To compare two different accelerated corneal cross-linkingprotocols in terms of postoperative visual acuity and topographicfindings (higher-order aberrations and keratometry values).Study Design: Retrospective comparative study.Methods: Sixty-five eyes of 43 patients (30 men and 13 women)who underwent two different accelerated corneal cross-linkingprotocols (10 min, 9 mW/cm2 and 5 min, 18 mW/cm2) for progressivekeratoconus were retrospectively analyzed. Patients were dividedinto two groups according to the accelerated corneal cross-linkingtreatment protocol: group 1 (10 min, 9 mW/cm2, 32 eyes of 21patients) and group 2 (5 min, 18 mW/cm2, 33 eyes of 22 patients).Uncorrected visual acuity and best-corrected visual acuity values andtopographic findings (central corneal thickness and flat and steepkeratometry values) were recorded preoperatively and 6 monthsafter corneal cross-linking treatment. High-order aberration valuesmeasured with Pentacam preoperatively and 6 months after cornealcross-linking were also recorded.Results: In both groups, a significant improvement was detected inthe uncorrected visual acuity and best-corrected visual acuity levelspreoperatively and 6 months postoperatively (group 1: p=0.001,p=0.001 and group 2: p=0.001, p=0.001, respectively). In addition,central corneal thickness values decreased significantly in both groups(p=0.006 and 0.001). Trefoil values showed no significant differencepreoperatively and 6 months postoperatively in group 1 (p=0.160and 0.620, respectively). In groups 1 and 2, coma values were foundto decrease significantly in the 6th postoperative month comparedwith preoperative values (p=0.001 and 0.020, respectively). Therewas no significant difference between preoperative and 6th monthpostoperative horizontal and vertical trefoil values in both groups(p=0.850 and 0.140, respectively). There was no significant differencebetween the two groups in terms of preoperative and 6th monthpostoperative higher-order aberrations, refractive errors, keratometryvalues, and uncorrected visual acuity and best-corrected visual acuitylevels.Conclusion: Both accelerated corneal cross-linking proceduresprovide similar improvement in topographic findings, coma valuesand visual acuity