What this Trial Is About

Researchers are evaluating two laser procedures to correct myopia and myopic astigmatism: a new method called CLEAR and the established SMILE technique. This study compares outcomes like how accurately each procedure corrects vision, clinical dry eye effects, tear protein changes, and corneal nerve recovery at 1, 3, 6, and 12 months after surgery. It also examines metabolic features of the removed corneal tissue and how precisely the laser is centered during each procedure. The goal is to determine if CLEAR provides vision results as good as SMILE with possible additional benefits. Participants will undergo both procedures, with CLEAR performed on one eye using the FEMTO LDV Z8 laser system and SMILE on the other eye using the VisuMax laser system. Both are flapless refractive surgeries that remove a corneal lenticule to reshape the eye. CLEAR involves low-energy laser pulses and allows recentering during docking, while SMILE has a steep learning curve with potential complications early on. The study uses a paired eye approach for internal control. During the 12-month follow-up, participants will attend post-operative visits to assess visual outcomes and ocular health. Researchers will measure refractive predictability, changes in tear proteins, corneal nerve regeneration, and laser centration accuracy. The study includes clinical exams, imaging, and laboratory analyses to monitor safety and effectiveness. The total participation time includes baseline measurements and regular assessments over one year.

Comparison of Femto LDV Z8 Corneal Lenticule Extraction for Advanced Refractive Correction (CLEAR) and Visumax Small Incision Lenticule Extraction (SMILE)