2-YEAR EXPERIENCE OF CORNEAL COLLAGEN CROSSLINKING IN KERATOCONUS TREATMENT

Aim. To assess reliability, efficacy, and stability of corneal collagen crosslinking (CXL) results for stage I‑II keratoconus.

Patients and methods. 2‑year (2012-2014) results of CXL were analyzed. CXL was performed on 20 eyes of 15 patients (13 men and 2 women, mean age 31 years). Stage 1 keratoconus was diagnosed in 13 eyes, stage 2 keratoconus was diagnosed in 2 eyes. Primary stage 1‑2 keratoconus was diagnosed in 17 eyes, keratoconus after corneal refractive surgery (LASIK, radial keratotomy) was diagnosed in 3 eyes. Preoperative and postoperative examination included uncorrected (UCVA) and best-corrected (BCVA) visual acuity measurement, pachymetry, corneal topography (total astigmatism measurement), and biomicroscopy. Follow-up period varied from 1 to 24 months.

Results. All patients reported on vision improvement. Preoperatively, mean UCVA and BCVA were 0.4 and 0.64, respectively. Postoperatively, mean UCVA and BCVA were 0.49 and 0.66, respectively. Preoperatively and postoperatively, total astigmatism was 2.1 D and 2.0 D, respectively, while mean central corneal thickness was 454 μm and 447 μm, respectively.

Conclusions. Corneal collagen crosslinking for stage 1‑2 keratoconus provides mild UCVA and BCVA improvement, decrease in total astigmatism and central corneal thickness. CXL provides stable results of treatment of primary stage 1‑2 keratoconus and keratoconus after corneal refractive surgery. 

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