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

Inclusion Criteria: * \>/= 21 years of age and \</= 50 years of age. * Cycloplegic spherical equivalent of \>-1.00D * Refractive cylinder -2.00 D or less; anisometropia \<1.00D * Best spectacle corrected visual acuity (BSCVA) of 6/12 or better in BOTH eyes. * Spherical or cylindrical error has progressed at -0.50D or less per year from date of baseline measurement. * Contact lens wearers must have removed contact lenses at least two (2) weeks before the baseline measurement. * No evidence of irregular astigmatism on corneal topography. * Available to attend post-operative examinations for a 12-month period. Exclusion Criteria: * Progressive or unstable myopia and/or astigmatism. * Clinical or corneal topographic evidence of keratoconus. * Patients who want bilateral SMILE procedure * Patients who want extracted corneal lenticule to be stored for future refractive surgery. * Residual, recurrent or active ocular disease such as uveitis, severe dry eyes, severe allergic eye disease, glaucoma, visually significant cataract and retinal disease. * Previous corneal surgery or trauma within the corneal treatment zone. * Corneal vascularisation within 1mm of the corneal treatment zone. * Taking systemic medications likely to affect wound healing, such as corticosteroids and antimetabolites. * Systemically immunocompromised. * Systemic disease likely to affect wound healing, such as diabetes, connective tissue disease and severe atopy. * Pregnant or nursing.