Purpose: To evaluate the surgical outcomes of microthin intracorneal ring segment (INTACS) implantation in advanced keratoconus.
Methods: INTACS implantation was performed in eyes with advanced keratoconus. The main outcome measures were uncorrected visual acuity, best spectacle-corrected visual acuity, change in mean refractive spherical equivalent (MRSE), and keratometry.
Results: Intacs were implanted in 14 eyes with advanced keratoconus. At 6 months, uncorrected visual acuity improved from 0.05 +/- 0.08 to 0.16 +/- 0.11 (P < 0.05), and best spectacle-corrected visual acuity improved from 0.50 +/- 0.23 to 0.67 +/- 0.00 (P = 0.01). The spherical refractive error improved from -6.68 D +/- 6.44 to -3.11 D +/- 3.08 (P = 0.03), whereas the cylindrical refractive error improved from -4.89 D +/- 1.91 to -3.64 D +/- 1.27 (P = 0.04). The MRSE reduced from -9.13 D +/- 5.62 to -4.93 D +/- 3.19 (P = 0.01), and the average keratometry decreased from 53.01 D +/- 3.70 to 49.42 D +/- 3.79 (P < 0.05). The results were stable from 6 months to 1 year. The procedure showed 100% safety, and more than 60% tolerated contact lenses. Younger age, male sex, and minimum central pachymetry of more than 400 microm seemed to be associated with better outcomes.
Conclusions: In this series, Intacs provided good results with respect to visual acuity, corneal topography, and MRSE in eyes with advanced keratoconus without major complications or the need for segment explanation. INTACS is potentially a safe and efficacious treatment option in the management of advanced keratoconus.