Comparative Study of Small Incision Lenticule Extraction Versus LASIK to Treat Myopic Presbyopia
To analyse and compare the clinical results with a 100% femtosecond procedure (SMILE) and with a conventional LASIK, to treat myopic presbyopic patients.
In this retrospective study, 33 patients were treated with SMILE using a VisuMax femtosecond laser and 42 patients with LASIK using the LBV software delivering an aspheric ablation profile with the MEL 80 platform. All patients were selected according the classical refractive surgery eligibility criteria and support a refractive dissociation included between +1.00 and + 1.50 diopters on the non dominant eye. The mean patient’s age was 47 years. The preoperative refraction ranged from –0.50 to –6.25 diopters with no cylinder up to 2.50 diopters. The clinical results were compared at 1, 3 and 6 months after surgery.
At 6 months, the visual outcomes are similar in both groups. 96% of patients raise 20/20 binocular Uncorrected Distance Visual Acuity and 100% raise 25/20 or more. The Mean Refractive Spherical Equivalent was -0.42 diopters for the distant eye. 95% patients obtain J3 or better. The analysis of postoperative corneal topography shows a modification of the Q factor which increases from 0.59+/- 0.17 in the SMILE group. The Dry Eye Severity Score is significantly better after SMILE compared to LASIK at 6 months postoperatively.
Both SMILE and LASIK procedure provide similar visual outcomes for far and near vision in using a refractive dissociation to treat myopic presbyopic patients. The modification of the corneal shape after SMILE seems to produce the same effect than the aspheric ablation profile with the Excimer laser MEL-80. However SMILE offers a minimally invasive procedure and less postoperative dryness.