this is an interventional prospective clinical study which was conducted to evaluate the efficacy, safety, predictability, ocular aberrations, and flap thickness predictability of Visumax femtosecond laser (FSL) compared to Moria M2 microkeratome (MK) in mild to moderate myopia.

This study included 60 eyes who were divided into two groups. Thirty eyes in group (I) in which the flap was created with Visumax FSL, while in group II (30 eyes) the Moria M2 MK was used. Keratometric, refractive, and aberrometric measurements were compared preoperatively and 3 months postoperatively. The intraoperative subtraction pachymetry (the SP 100 Handy pachymeter (Tomey, Nagoya, Japan) was used for preoperative pachymetry and flap thickness measurement.

Inclusion Criteria:

• Male and female patients were eligible for the study if they were older than 18 years and younger than 40 years.
• Stable myopia up to -6.0D and astigmatism up to -3.0D determined by manifest refraction for at least 6 months.
• best corrected distance visual acuity of at least 20/20, and stable keratometry after cessa¬tion of soft contact lens wear for at least 2 weeks.

Exclusion Criteria:

• any anterior seg¬ment pathology.
• any form of retinal degeneration. unstable myopia.
• severe dry eye.
• corneal thickness that would have resulted in less than 300 µm residual stromal thickness.
• Patients who had keratoconus or were keratoconus suspects.
• previous ocular sur¬gery.
• a history of herpes zoster ophthalmicus or herpes simplex keratitis.
• a history of a steroid-responsive rise in in¬traocular pressure (IOP) or a preoperative IOP of more than 21 mmHg.
• diabetes mellitus, autoimmune dis¬ease, connective tissue disease, and chronic use of systemic corticosteroid or immunosuppressive therapy were also excluded from the study.