Objective: To prospectively study the effects of the use of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, Calif) for the postoperative management of corneal ectasia resulting from laser in situ keratomileusis (LASIK).
Methods: In this prospective nonrandomized clinical trial, 10 eyes of 7 patients with post-LASIK corneal ectasia (2 men and 5 women) aged 33 to 46 years (mean +/- SD, 40.67 +/- 5.99 years) were included. The follow-up ranged from 6 to 24 months (mean +/- SD, 15.0 +/- 6.5 months). Two Intacs segments of thickness depending on the residual refraction of the patients were inserted in each eye.
Main outcome measures: Uncorrected visual acuity, best spectacle-corrected visual acuity, refractive outcome, and topographic findings after Intacs implantation.
Results: Intacs were successfully implanted in all eyes. Spherical equivalent error was statistically significantly reduced after Intacs implantation (pre-Intacs, mean +/- SD: -4.81 +/- 3.24 Diopters (D) (range, -13.75 to -2.50 D) to -0.96 +/- 2.93 D (range, -8.75 to 2.50 D) (P<.001). Pre-Intacs uncorrected visual acuity was 20/100 or worse in all eyes (range, counting fingers to 20/100) while at the last follow-up examination, 9 (90%) of 10 eyes had uncorrected visual acuity of 20/40 or better (range, counting fingers to 20/20). Three eyes maintained the pre-Intacs best spectacle-corrected visual acuity while the rest of the eyes (7) experienced a gain of 1 to 2 lines. The mean difference between pre-Intacs and last follow-up best spectacle-corrected visual acuity was a gain of 1.00 +/- 0.82 lines.
Conclusions: Intracorneal ring segments implantation improved uncorrected visual acuity and best spectacle-corrected visual acuity in patients with post-LASIK ectasia. Even though the results are encouraging, concern still exists regarding the long-term effect of such an approach for the management of post-LASIK ectasia.