Six-year follow-up of laser in situ keratomileusis for moderate and extreme myopia using a first-generation excimer laser and microkeratome

Abstract

Purpose To evaluate objectively and subjectively the long-term outcome of laser in situ keratomileusis (LASIK) in patients with high and very high myopia. Setting Department of Ophthalmology, Philipps University, Marburg, Germany. Methods Thirty-three eyes of 19 patients were followed for a mean of 76 months (range 50 to 84 months) after primary LASIK using the Keratom I excimer laser (Schwind) and the ALK microkeratome (Chiron). Refraction, glare, pachymetry, corneal topography, and tear-film secretion and stability were measured. At the last examination, patients also answered a 14-item questionnaire. Results Preoperatively, the mean spherical equivalent was –13.65 diopters (D). At 1 year, it was –0.25 D and after 6 years, –0.88 D. Fifteen percent of eyes lost ≥2 lines of best spectacle-corrected visual acuity (BSCVA), and 9% gained ≥2 Snellen lines. At the end of the study, 46% of eyes were within ±1.0 D of the attempted corrected and 88% were within ±3.0 D. There were 5 microkeratome-associated complications; 3 resulted in loss of BSCVA. The latest pachymetry showed a mean corneal thickness of 498.5 μm (range 396 to 552 μm). There were no cases of keratectasia. Seventy-five percent of patients noted an increase in their quality of life. Seventy-one percent were satisfied with their postoperative visual acuity; however, 75% noticed glare and halos at night. Conclusions Laser in situ keratomileusis correction of very high myopia did not cause keratectasia in the long term provided the corneal thickness was respected. A flap thickness setting of 130 μm with a first-generation microkeratome resulted in a high number of cut failures. Most patients were happy with the results despite a modest level of accuracy and glare.