EXCIMER-LASER CORRECTION OF MYOPIC ASTIGMATISM

The excimer laser allows the controlled ablation of corneal tissue to correct refractive error. By using a combination of spherical and slit apertures, it is possible to correct both myopia and astigmatism. We report the results of 139 consecutive eyes that had photoastigmatic re fractive keratectomy (PARK) for myopic astigmatism (myopia less-than-o r-equal-to -15.00 diopters [D] with astigmatism less-than-or-equal-to -6.00 D) and compare these results with 107 consecutive and concurrent eyes that received photorefractive keratectomy (PRK) for myopia (less -than-or-equal-to -15.00 D). The same excimer laser was used by 27 dif ferent surgeons. All patients were followed for at least three months. In the PARK group, 68% were within +/-1.00 D at six months and 77% we re within +/-2.00 D. In the PRK group, these figures were 87% and 97%, respectively. Uncorrected visual acuity of 20/40 or better was achiev ed in 72% of PARK and 90% of PRK patients at six months. Minor adverse reactions occurred in 6% of PARK and 11% of PRK patients. No signific ant surgeon effect was seen. Photoastigmatic refractive keratectomy pr ovides a realistic approach to the surgical correction of myopic astig matism and is comparable to PRK in safety and efficacy.