Purpose:
To evaluate the efficacy of myopic laser in situ keratomileusis (LASIK) based on preoperative keratometry (K).
Methods:
One hundred fifty patients (216 eyes) with preoperative spherical equivalent (SE) ranging from -2.00 to -5.99 diopters (D) underwent LASIK using the VISX STAR S2/S3 Excimer Laser Platform. Seventy-two patients (108 eyes) with a preoperative K value less than 42.0 D (Group 1) were compared with 78 patients (108 eyes) with a preoperative K value greater than or equal to 46.0 D (Group 2). Eyes were matched for preoperative age, spherical equivalent, cylinder, and preoperative pachymetry prior to statistical analysis. Primary outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, keratometry, and manifest refraction at 1, 3, 6, and 12 months postoperatively.
Results:
Moderately myopic eyes with flat corneas preoperatively had significantly better LASIK outcomes compared to eyes with steep corneas. The mean 6-month SE in group 1 was -.19 +/- .47 and in group 2 was -.37 +/- .50 (p-value=.007). Eighty-three percent of eyes in group 1 were within 0.25 D of plano, compared to 59% in group 2. Furthermore, one eye in group 1 lost one line of CDVA compared to eight eyes in group 2.
Conclusions:
Moderate myopes with flatter corneas preoperatively have significantly better postoperative visual outcomes when compared with eye whose corneas are steeper prior to myopic LASIK.
Keywords: refractive surgery: corneal topography • refractive surgery: LASIK