Laser in situ keratomileusis for correction of induced astigmatism from cataract surgery

Abstract

Purpose: To evaluate the efficacy, predictability, stability, and safety of laser in situ keratomileusis (LASIK) to correct residual astigmatism after cataract surgery.

Methods: LASIK was performed on 20 eyes of 20 patients with refractive myopic or mixed astigmatism (3.00 to 6.00 D) at least 1 year after extracapsular cataract extraction with posterior chamber intraocular lens implantation without complication. Each eye received bitoric LASIK with the Nidek EC-5000 excimer laser and the Automated Corneal Shaper microkeratome.

Results: At 6 months after LASIK, mean refractive cylinder decreased from 4.64+/-0.63 D to 0.44+/-0.24 D (P<.001). Mean percent reduction of astigmatism was 90.4+/-5.0% (range 80% to 100%). Mean spherical equivalent refraction decreased from -2.19+/-0.88 D (range -1.00 to -3.88 D) to -0.32+/-0.34 D (range -1.25 to +0.38 D) (P<.001). Vector analysis showed that the mean amount of axis deviation was 0.7+/-1.2 degrees (range 0 degrees to 4.3 degrees) and the mean percent correction of preoperative astigmatism was 92.1+/-5.9% (range 85.6% to 108%). Eighty-five percent of all eyes had a mean spherical equivalent refraction and mean cylinder within +/-0.50 D of emmetropia. Change in spherical equivalent refraction and cylinder from 2 weeks to 6 months was < or = 0.50 D in 90% (18 eyes) and 95% (19 eyes), respectively. Spectacle-corrected visual acuity was not reduced in any eye. Diffuse lamellar keratitis occurred in three eyes (15%) after LASIK, and were treated successfully with eyedrops.

Conclusion: LASIK was an effective, predictable, stable, and safe procedure for correction of residual myopic or mixed astigmatism ranging from 3.00 to 6.00 D with a low spherical component after cataract surgery.