Purpose. The purpose of the current study was to evaluate the long-term functional results based on keratometric measurements, spherical and cylinder equivalent in patients with progressive keratoconus treated with conventional “epi-off” corneal collagen cross-linking (CXL). Methods. We conducted a retrospective study in which 113 eyes from 90 keratoconus-treated patients with CXL between 2006 and 2008 in Oculens Eye Clinic from Cluj-Napoca, Romania, were included. The diagnosis of keratoconus was based on corneal topography and its clinical signs. All patients were evaluated preoperatively, and a follow-up was performed at 1, 3, and 6 months and every year from 1 to 10 years after conventional CXL. Results. All keratometry measurements improved significantly during the follow-up. Compared to preoperative values, the improvement of Kmax become statistically significant at 1 year after CXL (mean change compared to baseline −0.9 D, p<0.001) and remained statistically significant thereafter up to 10 years (mean change compared to baseline −2.3 D, p<0.001). As compared to preoperative values, mean spherical equivalent and mean cylinder improved during the follow-up, from a mean of −6.22 D before CXL to a mean value of −5.0 at 10 years, following CXL for spherical equivalent and from −4.4 D at baseline to −3.4 D at 10 years for cylinder (p<0.05 for both). Uncorrected visual acuity increased, remaining statistically significant, by 0.104 logMAR at 10 years after CXL (p=0.0015), and best-corrected visual acuity increased by 0.135 logMAR at 10 years after CXL (p=0.015). We did not observe any case of severe complication. Conclusion. Our results show that CXL has a favorable effect on the progression of KC. The reduced K values, cylinder and spherical equivalent, and increased visual acuity remained the same 10 years after the procedure.

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IntroductionCorneal thinning disorders caused by keratoconus often lead to protrusion, irregular astigmatism, and even perforation. Keratoconus, like other corneal ectasia, does not have a known cause. Severe cases of keratoconus may require correction or restoration of tectonic integrity of the cornea by surgical means. Intracorneal ring segments are a new modality in the treatment of corneal ectactic disorders. A new technique of stopping the evolution of keratoconus and strengthening the cornea is combining techniques of intrastromal corneal ring implantation and corneal collagen cross-linking. The objective of the study is to compare the effectiveness of combined procedures: intrastromal corneal ring implantation followed by cross-linking, with cross-linking followed by intrastromal corneal ring implantation.MethodsThe study comprised two groups of patients with different evolutionary stages of keratoconus, which met the eligibility criteria for intrastromal corneal ring segment implantation and corneal collagen cross-linking. Group 1 included patients (41 eyes) who underwent intrastromal corneal ring implantation followed by cross-linking and group 2 (30 eyes) included patients who underwent cross-linking first followed by intrastromal corneal ring implantation.ResultsA decrease in Km values of about 1.5 D and refraction was observed in group 1, compared to a decrease in Km values of about 1 D and refraction in group 2. Recovery of visual acuity was higher in group 1 than group 2.ConclusionsThe sequence of intrastromal corneal ring implantation followed by cross-linking proved to be more effective in reducing Km values, spherical equivalent and cylinder compared with cross-linking followed by intrastromal corneal ring implantation.

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