Noncontact holmium:YAG laser thermal keratoplasty for hyperopia

To describe our experience with noncontact holmium:YAG laser thermal keratoplasty (Ho:YAG LTK).

Refractive Surgery and Cornea Department, Clinica de Ojos Dr. Nano, Buenos Aires, Argentina.

In this retrospective study, 182 hyperopic eyes from 116 patients were treated with noncontact Ho:YAG LTK. Mean age was 50 years +/- 7 (SD), and the spherical equivalent (SE) of the subjective mean refraction (SMR) was +2.50 +/- 0.87 diopters (D). Eyes with corneal power of more than 45 D, corneal pachymetry thicker than 550 microns, and previous corneal surgery or disease were excluded. Holmium:YAG laser parameters include one to three rings of eight spots arranged in a radial and symmetrical array. Pulse energy was 240 mJ, with five pulses per spot. Patients were followed for 12 months.

The mean uncorrected visual acuity from 3 to 12 months was 20/40 (20/200 to 20/25), improving an average of three Snellen lines. Mean best spectacle-corrected visual acuity was 20/25 at all postoperative examinations, the same as preoperatively. Mean SE of the SMR was +1.50 +/- 0.98 D (range -0.75 to +4.50 D) at 6 months and +1.25 +/- 0.96 D (+0.25 to +3.25 D) at 1 year. After 9 months, 17% of operated eyes were retreated.

In this study, Ho:YAG LTK was safe and effective, provided satisfactory correction of low hyperopia, and had a low complication rate. Good patient selection is the key to obtaining good results.