Efficacy and safety of Intacs SK in moderate to severe keratoconus.

Purpose: To examine the safety and efficacy of Intacs SK for moderate to severe keratoconus (KC) using femtosecond technology.

Materials And Methods: This prospective, non-comparative study included 37 contact lens intolerant keratoconic eyes (stage II-III) of 24 patients who underwent femtosecond-assisted Intacs SK implantation. Inclusion criteria were mean K readings <56.00 D, corneal thickness >400 μm at the incision site, mesopic pupil <6.50 mm. Evaluation included manifest refraction, slitlamp examination, corneal topography, uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA). P < 0.05 was statistically significant.

Results: Thirty-one (83.8%) eyes were classified as Amsler-Krumeich's stage II and 6 (16.2%) were stage III. Mean central pachymetry was 490.3 ± 37.4 μm. UDVA at 6 months post-operatively was significantly better than pre-operatively (0.90 log MAR ± 0.52 standard deviation [SD] versus 0.32 ± 0.27 logMAR; respectively, P < 0.0001), as was the spherical equivalent (SEq) (-3.64 ± 2.52 D vs. -1.84 ± 2.2 D; P < 0.0001). The mean CDVA and manifest cylinder improved compared with pre-operatively (P = 0.319 and P = 0.078, respectively). Average keratometry decreased significantly from 48.50 ± 3.08 D to 44.40 ± 3.03 D (P < 0.0001).

Conclusion: Implantation of Intacs SK using femtosecond laser in moderate to severe KC is safe and effective.