Purpose: To investigate the refractive results and corneal pachymetric changes after laser in situ keratomileusis (LASIK) with an inferior hinge.
Methods: Forty-six eyes of 23 patients who underwent LASIK with an inferior hinge were involved in this prospective study. All patients had a complete ophthalmic examination including uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, computerized corneal topography (Orbscan II Corneal Topography System; Orbscan Inc, Salt Lake City, Utah), air-puff tonometry, slit-lamp examination of the anterior segment, and fundus examination.
Results: Preoperatively, mean sphere was -4.09+/-0.27 diopters (D) (range: -8.00 to -0.25 D), mean cylinder was -0.60+/-0.11 D (range: -3.25 to 0.00 D), and mean spherical equivalent refraction was -4.39+/-0.27 D (range: -8.63 to -1.50 D). At 1 month postoperatively, mean sphere was -0.04+/-0.01 D (range: -0.25 to 0.00 D), mean cylinder was -0.01+/-0.01 D (range: -0.50 to 0.00 D), and mean spherical equivalent refraction was -0.04+/-0.02 D (range: -0.00 to -0.50 D). At 1 month postoperatively, no eyes lost any lines of BSCVA.
Conclusions: Laser in situ keratomileusis with an inferior hinge is an alternative technique, which was safe and effective in our series. Further studies with long-term follow-up comparing the incidence of corneal ectasia in eyes with a superior hinge to that in eyes with an inferior hinge are recommended.