What Is Involved in Laser Eye Surgery for Astigmatism?

Myopic laser surgery is a kind of laser surgery to correct myopia . It includes laser optical keratectomy (PRK), excimer laser in situ keratomileusis (Lasik, IK) and excimer laser Keratomileusis (LASEK, referred to as EK), wavefront aberration-guided excimer laser surgery (Torsion Lasik, referred to as TK), femtosecond, full femtosecond laser development stages.

Myopic laser surgery

Myopic laser surgery is a method to correct myopia

1. At least 18 years of age, have a healthy mental state, have the desire to take off their glasses, and can bear the risk of failure of excimer surgery (the risk of surgery is small, but it is likely to relapse);

2. After examination by the doctor, the eye indicators meet the requirements of the operation, that is, the eye is free of diseases and inflammation;

3. If contact lenses are worn, the soft lens should be removed for 2 weeks, and the rigid lens should be removed for more than 4 weeks (you can change the frame glasses for pre-operative examination);

4. If it is the second excimer operation, LASIK should be spaced 3 to 6 months, PRK should be spaced 1 year. If there is far, shortsightedness and astigmatism after penetrating corneal transplantation, it should be spaced more than 1 year.

5. The degree of myopia has been relatively stable in the past two years, and excimer surgery can be performed by deepening it no more than 50 degrees each year;

6. There are no diseases that are restricted by excimer surgery, such as cardiovascular diseases.

1. Active eye inflammation such as acute conjunctivitis, keratitis, and dacryocystitis.

2. Patients with keratoconus, glaucoma, dry eye and other diseases.

3. Patients with fundus hemorrhage and retinal detachment.

4. Patients with diabetes, scar constitution, collagen disease and diseases that affect corneal wound healing.

5. Patients with severe amblyopia.

6. Highly myopia drivers who drive at night.

7. Those who have extremely high vision requirements and serious thought concerns.

Common eye problems early after surgery

On the day of the operation, you may experience symptoms such as tearing, photophobia, and foreign body sensation in the eyes. At this time, you should wipe the tears after the tears flow out. Do not touch the eyes directly with a paper towel or towel. At the same time, try to rest your eyes closed, reduce eye movements, and prohibit rubbing your eyes. Very few patients may experience mild eye pain or appear after surgery

Misunderstanding 1: Laser myopia surgery has sequelae and hidden dangers

There are certain risks to any surgery. Surgery requires good cooperation between doctors and patients. Laser myopia surgery has been developed in China for 20 years. Technology and equipment have been continuously developed and improved. Clinicians have more and more experience. Laser myopia surgery is especially Femtosecond laser myopia surgery is very mature and safe.

Comprehensive and meticulous preoperative examinations have strictly screened the contraindications to surgery, while strictly grasping the scope of indications, which has reduced surgical complications to a very low level.

Myth 2: Any degree of laser myopia surgery can be corrected

Laser myopia surgery is a kind of corneal surgery. Its principle is to excise the corneal stromal tissue with an excimer laser to change the curvature of the cornea so that the light can focus on the retina, thereby achieving the purpose of correcting myopia. Therefore, the correction range is closely related to the thickness of the cornea; in patients with ultra-high myopia above 1200 degrees, a certain degree of residual corneal tends to remain after the safety corneal thickness is reserved after surgery.

Therefore, patients over 1200 degrees are generally not suitable for surgery, and ICL lens implantation surgery should be considered.

Misunderstanding 3: There is no age limit for laser myopia surgery

Myopia patients under the age of 18 years often have unstable development of refractive status, and the degree of myopia may be further deepened. Myopia patients above 50 years old often have presbyopia, and may have opacity of crystals. In this case, myopia, astigmatism, etc. Can be corrected at the same time during cataract surgery.

Therefore, not all myopia patients are suitable for myopia surgery.

Myth 4: Laser myopia surgery can only treat myopia, but not astigmatism

Patients with myopia often have a certain degree of astigmatism. Generally, laser myopia surgery can correct astigmatism at the same time as correcting myopia. However, it should be noted that due to the reasons of the equipment, the astigmatism can only be corrected within 600 degrees.

Misunderstanding 5: Eyesight can reach 1.5 after laser myopia surgery

The human eyeball is a fine refractive system composed of the cornea, lens, vitreous body, retina, etc. Any lesion or defect in any tissue will cause vision damage. Everyone's vision is different, often because of the overall difference in the refractive system of the eyeball; it is difficult to fully adjust the refractive status of the entire eyeball just by adjusting the corneal refractive power.

Therefore, in general, laser myopia surgery can help patients achieve vision correction before surgery, but can not expect to have a vision of 1.5.

Experts will introduce in detail the four major factors affecting the safety of myopia laser surgery:

Surgeon

Factors affecting the quality of excimer surgery

The experience of the surgeon is decisive for the safety of the operation. Because the operation of the corneal microtomy is quite complicated, it requires an ophthalmologist who is skilled in technical experience to operate. Experienced physicians can also deal with various complex individual differences during the operation to ensure the safety of each patient's surgery, which is difficult for inexperienced physicians to do.

Surgical equipment

Factors affecting the quality of excimer surgery

The difference in the performance of the equipment directly determines the quality of the operation, which is mainly reflected in the accuracy of surgical treatment and the smoothness of the cornea after surgery, the size of the diameter of the cutting area of the operation, and the thickness of the remaining cornea. Accurate cutting can ensure that the surgery achieves predicted vision and avoids undercorrection (still a small amount of myopia) or overcorrection to hyperopia; smooth cornea means that there is no irregular astigmatism; larger surgical area means no night glare Phenomenon; the thickness of the remaining cornea is large and does not occur iatrogenic

Preoperative examinations are different

Surgery is not an isolated process. Strict routine ophthalmological examinations should be performed before surgery to exclude unsuitable conditions. It is necessary to make accurate optometry and check the corneal topography. The corresponding data must be accurately entered into the computer. The data processed by the computer must be imported into the surgical equipment. The laser equipment must be accurately adjusted before each operation. These processes must not be sloppy.

Different doctors

Good equipment works best with skilled doctors. The human body is a large, complex system with delicate relationships between organs. The difference between experienced experts and novice physicians is that experts can design surgical procedures based on the patient's situation, which can effectively prevent risks.

Different materials

The price of imported surgical materials and domestic materials for the same operation varies greatly. The blade used to make the corneal flap is very expensive. Some hospitals use the corneal knife repeatedly to save costs, which can easily cause infection and even blindness in patients. All consumables in a regular eye hospital can only be used once, no matter how expensive they are.

Different ways

The mainstream refractive surgery in the world today is excimer laser surgery. This kind of surgery preserves corneal epithelium with less damage, less pain for the recipient, easy recovery after surgery, and less infection, but the cost of surgery is high. The world's most advanced surgical method is the femtosecond laser. This surgical method has no knife during the whole process, the operation is safer and more accurate, the reset is closer to the original ecology, and the surgical vision is more perfect.