Clinical Evaluation of LASEK for High Myopia Correction between the Triple-A Profile and the Zyoptix Tissue Saving Profile

Abstract

Purpose. To compare the effects of correcting high myopia using the MEL®90 Triple-A profile LASEK at a 500 Hz pulse rate (Triple-A group) versus the Zyoptix tissue-saving ablations of Technolas 217z laser platform at 100 Hz (TS group). Methods. This retrospective study included 50 eyes in the Triple-A group and 42 eyes in the TS group with manifest refraction spherical equivalent (MRSE) of −6 diopters (D) to −10 D. We compared uncorrected distance visual acuity, MRSE, corrected distance visual acuity, and postoperative complications at 1 month, 3 months, and 6 months. Results. At 6 months after refractive surgery, the efficacy index of Triple-A group was significantly higher than that of the TS group (1.03 ± 0.12 vs 1.00 ± 0.11, P=0.04). The MRSE postoperatively in the Triple-A group was significantly lower than that in the TS group (0.25 ± 0.18 vs 0.38 ± 0.23, P<0.01). The safety indices in the two groups were almost the same after 6 months of surgery (1.03 ± 0.07 vs 1.04 ± 0.11, P=0.63). The proportion of eyes which achieved ±0.13 D was significantly higher in the Triple-A group than that in the TS group at 1 month (80% vs 59.5%, P=0.03), 3 months (82% vs 61.9%, P=0.03) and 6 months (84% vs 64.3%, P=0.03). The changes in refraction 6 months after surgery comparing with 1 month after surgery were 0.12 ± 0.10 D in the Triple-A group and 0.13 ± 0.08 D in the TS group (P=0.56). All (100%) of the patients in the Triple-A group and 50% of the patients in the TS group had a UDVA of 20/16 at 6 months after surgery (P<0.01). The induced spherical aberrations and total HOAs in the Triple-A group were significantly lower than those in the TS group (0.17 ± 0.02 μm vs 0.23 ± 0.02 μm, P<0.01; 0.20 ± 0.04 μm vs 0.39 ± 0.03 μm, P<0.01) at 6 months after surgery. The mean reduced corneal thickness was 113.06 ± 10.5 μm in the Triple-A profile group and 121.43 ± 23.46 μm in the TS group (P=0.02). No patient in either group had haze and high intraocular pressure 6 months after surgery. Conclusion. For treatment of high-myopia patients, the Triple-A profile was more effective, predictable, and accurate than the Zyoptix tissue-saving profile. Meanwhile, the Triple-A profile had less induced spherical aberrations, total HOAs, and cornea ablation depth than the Zyoptix tissue-saving profile. Patients in the Triple-A group with 500 Hz pulse rate treatment achieved superior results. The two surgical procedures were equivalent in terms of safety and stability.

Comparison of Corneal Densitometry and Visual Quality after Small Incision Lenticule Extraction (SMILE) and Laser Epithelial Keratomileusis (LASEK): One‐Year Comparative Study

“…Our findings partly confirmed those of Yu et al who reported no difference in visual outcomes after SMILE and LASEK for low-to-moderate myopia at 3 months postoperatively [28]. Our previously published studies also proved the safety and stability of LASEK for the correction of mild, moderate, and high myopia [29,30]. However, SMILE became a superior choice over LASEK in terms of lesser intensity of postoperative pain.…”