Myopia Correction Surgery

Myopia correction surgery is to cut at the center of the cornea of the eye, so that the focal length of the human eye changes, so as to achieve the purpose of treating myopia. Currently, excimer laser surgery is generally used, which is a very effective myopia correction. means. Indication 1. The patient has the requirement to pick up the mirror. 2. The age is 18 years old (preferably 20 years old). 3. The diopter is stable in the past two years. 4, correction of diopter range: myopia is best not to exceed 1500 degrees, astigmatism does not exceed 600 degrees, farsightedness does not exceed 600 degrees. 5, anisometropia. 6, the current wear contact lens: soft mirror should be stopped for more than 2 weeks, hard mirror should be stopped for more than 3 weeks, OK mirror should be stopped for more than 1-3 months. 7. The corneal thickness is greater than 450 um (depending on the refractive state). 8, no active diseases in the eye. Contraindications Absolute contraindications: (1) severe dry eye syndrome; (2) keratoconus or keratoconus tendencies; (3) blepharitis; (4) proliferative diabetic retinopathy; (5) exophthalmia, incomplete closure of the eyelids; (6) Systemic immunity and collagen diseases; (7) Scar physique. Relative contraindications: (1) Monocular patients should not be treated for myopia; (2) Systemic immunity and collagen disease should not be treated during the active period; (3) penetrating keratoplasty may cause endothelial cell damage and rejection of the graft, so it must be used with caution; (4) For patients with weak corneal epithelial adhesion, excimer laser surgery should be avoided as much as possible. Preoperative preparation First, eye examination Includes naked eye vision and wearing glasses for best corrected vision. Second, intraocular pressure examination To rule out the possibility of high intraocular pressure and glaucoma. Third, refractive examination Including computer optometry, medical optometry and dilated optometry three steps. Whether the optometry is correct or not directly affects the surgical outcome. Fourth, the anterior segment and fundus examination Focus on the corneal transparency, whether the cornea has scars, whether the crystal is turbid, whether the fundus is opaque or fundus lesions. Five, wavefront aberration check In addition to low-order aberrations such as myopia, hyperopia, and astigmatism, there are still high-order aberrations that seriously affect visual quality, and high-order aberration data is collected as a basis for diagnosis and surgery. Six, corneal curvature examination Eliminate the possibility of keratoconus and flat cornea. Seven, corneal thickness measurement If the patient is highly myopic, you should pay attention to the depth of the corneal center and explain the situation to the patient before surgery. Eight, corneal topographic examination The main purpose is to understand the regularity and symmetry of the entire corneal surface, and to exclude abnormal conditions such as keratoconus. Surgical procedure First, before surgery Before the operation, the doctor will use eye wash with sterile saline and chloramphenicol eye drops for about 5 to 10 minutes to reduce or avoid eye infection. Second, intraoperative 1. Anesthesia Eye: At the beginning of the operation, first anesthetize the eye drops. Use a special anesthetic to drip on the eyeball, let it lose pain, but the touch will still exist. 2, the corneal flap: First, the opener to help patients blink in the entire laser treatment of myopia surgery. Then the doctor put a suction ring on the opened eyeball to make the corneal flap. The process is only a few seconds, and the patient may feel pressure on the eye, or short-sighted vision, darkness and some pain. 3, laser engraving: After the corneal flap is made, the doctor gently pry open the corneal flap with a triangular sponge, and use the laser to perform the engraving on the cornea according to the data of the laser treatment instrument input in advance. The cutting area with a deep degree of myopia is correspondingly larger and takes a little longer. There will be a string of light and a little burning odor, the patient does not have to worry, this is a normal photochemical reaction when the laser works. Also note that although the laser can track the subtle activity of the eyeball in 1/10 second, it is best to keep an eye on it as required by the doctor. After the carving, the doctor covered the corneal flap with a sponge and rinsed the eyes. The operation of such an eye is done, and then the same step is used to make the other eye. 4, the surgery is completed: the doctor will use a slit lamp microscope to check the corneal flap reset.