Purchase this article with an account.
K. L. Fry, S. Greenstein, P. Hersh; One Year Outcomes After Corneal Collagen Crosslinking for Keratoconus and Ectasia. Invest. Ophthalmol. Vis. Sci. 2010;51(13):3474. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Clinical outcomes were assessed after corneal collagen crosslinking (CXL) for keratoconus (KC) and ectasia.
CXL (UVX; Peschke Meditrade GmbH), was performed on 59 eyes (50 patients), 40 eyes with KC and 19 eyes with ectasia, in a prospective, randomized, controlled clinical trial. Clinical outcomes including uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), manifest cylinder, and manifest refraction spherical equivalent (MRSE) were assessed pre- and 1 year postoperatively. Topography changes using the Pentacam; Kmax and Kavg, were also determined. Corneal biomechanical parameters, corneal hysteresis (CH) and corneal resistance factor (CRF) were measured using the Ocular Response Analyzer (ORA)(Reichert Inc.).
In the entire cohort, mean UCVA preoperatively was 20/149 and postoperatively was 20/133 (p=0.11). BCVA was significantly improved from 20/47 to 20/35 (p<.001). MRSE improved by 1.9D (p=0.04), although manifest cylinder remained unchanged after CXL. Topographically, Kmax and Kavg flattened by 2.5D (p=0.01) and 0.8D (p<.001), respectively, at 1 year. ORA parameters, CH and CRF did not significantly change following CXL.In the stratified subgroups, KC eyes showed no significant change in UCVA while BCVA improved from 20/51 to 20/37 (p<.001). MRSE improved by 1.0D (p=0.11), but failed to reach statistical significance. Manifest cylinder remained the unchanged after CXL. Topographically, Kmax and Kavg, flattened by 3.1D (p=0.02) and 0.8D (p<.001), respectively. No significant changes in CH or CRF were seen. Similarly, ectasia eyes, showed no significant change in UCVA while BCVA improved from 20/38 to 20/30 (p=0.003). MRSE improved by 1.5D (p=0.21) but failed to reach statistical significance. Manifest cylinder remained unchanged after CXL. Topographically, mean Kmax decreased by 1.1D (p=0.08), and Kavg failed to reach significance as well. No significant changes in CH or CRF were seen.
Overall, CXL was effective at improving BCVA, MRSE, Kmax, and Kavg. At 1 year postoperatively, more topographical changes were significant in patients with KC than ectasia. Cornea biomechanical parameters, CH and CRF were unchanged.
Clinical Trial: :
www.clinicaltrials.gov NCT 00647699, NCT 00674661
This PDF is available to Subscribers Only