Myopic keratomileusis in situ: A preliminary report

Abstract
We describe a technique and report a retrospective evaluation of myopic keratomileusis in situ. Surgery was performed on 32 eyes, with a mean follow-up time of 128.7 days (range 90 to 194 days). The average reduction of myopia was 8.48 diopters (D) when measured by refraction and 3.96 D by keratometry (minor axis). A statistically significant Pearson correlation coefficient of 0.49 (P = .01) was found between these two variables. Postoperative mean manifest spherical equivalent was -1.70 D (standard deviation 2.54 D). Mean cylinder correction increased -0.48 D (range -2.25 to 2.00 D). Uncorrected visual acuity improved after surgery in all eyes, but in 14 eyes the best corrected visual acuity diminished. Multiple regression model disclosed a limited predictability of the technique. Complications included diminution of best corrected visual acuity, under- and overcorrections, increase in keratomeric astigmatism and cylinder correction, keratitis, delayed corneal epithelialization, interface amorphous deposits, monocular diplopia, interface epithelialization, and opacification. The most frustrating was an elusive postoperative cycloplegic refraction. In our hands, myopic keratomileusis in situ was not a technically safe, precise, and predictable technique for correction of myopia. Further improvement in the technique and equipment may provide better results.