Predictability and stability of refraction with increasing optical zone diameter in hyperopic LASIK

Abstract

Objective:We undertook a prospective nonrandomized study to assess refractive outcome and patient satisfaction with hyperopic laser in situ keratomileusis (LASIK) using variable optical zone diameters in correction of hyperopia of more than 4.00 diopters.Methods:Fourteen adults (comprising 28 hyperopic eyes) underwent hyperopic LASIK correction for hyperopia of more than 4.00 diopters. The sample was divided into two groups. Group 1 included the right eyes of the 14 patients who underwent hyperopic LASIK using a 6.5 mm optical zone diameter. Group 2 comprised the left eyes of the same patients with the only difference being that the optical zone diameter was 6.0 mm.Results:The mean age of the patients was 36.42 ± 5.10 years. Group 1 eyes had a median (range) preoperative uncorrected visual acuity (UCVA) of 0.79 (0.52) and best-corrected visual acuity (BCVA) of 0.15 (0.08). Group 2 had a median preoperative UCVA of 0.79 (0.60) and BCVA of 0.15 (0.08). The median postoperative UCVA in Group 1 was 0.17 (0.21) and BCVA was 0.15 (0.13). In Group 2, the median postoperative UCVA was 0.30 (0.32) and BCVA was 0.15 (0.26). Group 1 had a median preoperative refraction of +5.37 (1.75) diopters and the median postoperative refraction at one week was −0.23 (1.25) diopters, at three months was +0.75 (0.75) diopters, and at six months was +0.75 (1.00) diopters. Group 2 had a median preoperative refraction of +5.00 (1.75) diopters, and the median postoperative refraction at one week was +0.13 (1.5) diopters, at three months was +1.00 (0.75) diopters and at six months +1.25 (1.25) diopters. The difference was statistically significant between groups 1 and 2. The difference within each group was also significant. Group 1 eyes were stabilizing after the three-month period in contrast with Group 2 in which the refractive changes continued throughout the follow-up period.Conclusion:Larger optical zone diameter in correction of hyperopia of more than 4.00 diopters was more predictable, stable and safe.

Long-Term Followup of LaserIn SituKeratomileusis for Hyperopia Using a 213 nm Wavelength Solid-State Laser

“…The percentage of 1-line BSCVA loss was the lowest in the 6 × 9 mm group showing a better safety profile. Lastly, El-Helw and Emarah [ 27 ] concluded that increasing the optical zone diameter is more predictable and stable in the correction of hyperopia. In our study, accuracy and safety were similar to previous studies wherein larger optical zones were used.…”

Lasik as a Solution for High Hypermetropia

“…Complications in this study were loss of 2 lines in twoeyes (0.74%), loss of 1 line in one eye (0.37%), diffuse lamellar keratitis (DLK) in three eyes (1.13%), prolonged dry eye in nine patients (18 eyes) (6.7%) even after 3 months postoperatively. Loss of lines varies between studies (18, 19), older studies state that the higher hyperopia and the smaller optical zone, loss of lines and less efficient results are expected (7). Later, surgical safety was defined as loss of 2 or more lines of CDVA at 6 months between 1 and 5% (21).…”

Efficacy and safety of small-incision corneal intrastromal lenticule implantation for hyperopia correction: a systematic review and meta-analysis

“…For patients who want to correct hyperopia through refractive surgery, transepithelial photorefractive keratectomy (T-PRK), femtosecond laser-assisted in-situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) can be used for the correction of hyperopia. These surgical methods can effectively correct hyperopia and ametropia; however, they all increase the risk of corneal swelling, refractive regression, and corneal epithelial implantation after surgery (2)(3)(4).…”