Excimer laser refractive corneal surgery, including excimer laser refractive keratomileusis, excimer laser subepithelial keratomileusis and excimer laser in situ keratomileusis, is the safest and most effective surgical method to correct myopia.
The indications for surgery are
1, age: generally 18 years of age or older.
Refractive stability: relatively stable refractive error in the past 2 years, with an annual increase of not more than 0.50D (50 degrees).
3, the range of refraction: myopia preferably not more than minus 10.00D, excimer laser refractive keratomileusis preferably not more than minus 6.00D; astigmatism preferably not more than 5.00D.
4. Patients with refractive disparity whose refractive power is not the same in both eyes.
5, the best preoperative corrected visual acuity: low to moderate myopia not less than 0.8, high myopia not less than: 0.3.
6.Patients wearing corneal contact lenses: soft lenses should be stopped for 1-2 weeks, hard lenses should be stopped for 2-3 weeks, and lenses should be stopped for 3-6 months.
7, corneal thickness: greater than 470um.
8, Re-operators: interval of 3 to 6 months, preferably more than 1 year; Excimer laser refractive keratomileusis: preferably more than 1 year; RK: preferably more than 2 years.
9, eye examination without active eye disease.
10, psychological factors: the patient himself has a healthy psychological state.
11.The patient himself has the requirement of lens removal: he does not like to wear frame glasses or corneal contact lenses.
Contraindications to surgery:
1.Absolute contraindications
(1) Severe dry eye disease.
(2) Cone cornea or tendency to cone cornea.
(3) Blepharitis.
(4) Proliferative diabetic retinopathy.
(5) Proptosis, incomplete eyelid closure.
(6) Systemic immune and collagen diseases.
(7) Scarring.
2.General contraindications
(1) Monocular patients should not undergo excimer laser surgery.
(2) Systemic immune and collagen diseases should not be treated during the active period.
(3) Patients with weak corneal epithelial adhesion should avoid excimer laser surgery as much as possible, which often results in partial or total epithelial peeling, making epithelial implantation more dangerous and slowing down the recovery of vision.