In recent years, with the popularization of electronic devices, the "glasses family" has shown a trend of younger age. On June 5, 2020, the National Health Commission released the first white paper on eye health in mainland China, the white paper on eye health in China, which pointed out that the overall incidence of myopia in children and adolescents in mainland China is 53.6%, and the overall incidence of myopia in college students exceeds 90%. However, many people feel that myopia is not a big deal and can be cured by surgery. So, what exactly is myopia surgery, is it safe, can anyone do it, and what do I need to pay attention to before and after myopia surgery?
Principles of myopia surgery
Myopia surgery can be divided into two categories: intraocular surgery and corneal surgery, depending on where the surgery is performed.
Intraocular surgery, also known as intraocular refractive surgery (ICL), is mainly for patients with high myopia. This method involves the implantation of corrective lenses in the eye. This surgical procedure is reversible, meaning that the corrective lenses in the eye can be removed or replaced. However, it should be noted that intraocular surgery is generally suitable for patients with a prescription of more than 1000 degrees, or a thin corneal thickness and abnormal corneal curvature. Although intraocular surgery is reversible, the pre- and postoperative examinations of intraocular lens implantation are complex, and postoperative follow-up is required, usually every 3-6 months. Therefore, corneal surgery is more appropriate for patients with myopia below 1000 degrees and corneal conditions permitting.
Corneal surgery, i.e., corneal refractive surgery, has a wide audience. This surgery is performed on the surface of the eyeball, that is, on the cornea, using laser energy to ablate or cut the cornea, and cut off or remove a certain thickness of corneal tissue according to the degree of myopia corrected according to the need. Corneal surgery is currently a relatively common myopia surgery, including half femtosecond, full femtosecond, etc. The so-called "femtosecond" laser surgery is a femtosecond laser device to make an open corneal flap, and then use an excimer laser to perform corneal ablation in an "ablative" way. In the "ReLEx" laser surgery, there is no need to make a corneal flap, but to make a lenticule by starting femtosecond laser scanning twice, and make a small superficial incision of 2-4 mm above the cornea, and remove the cut lenticule, so as to achieve the purpose of changing the corneal refraction to correct vision. It should be noted that although ReLEx has a faster recovery and is safer, it is not suitable for patients with thin corneas.
"Half femtosecond" laser surgery
"ReLEx" laser surgery
The technology of myopia surgery is relatively mature, but no treatment method can be said to be absolutely safe, and myopia correction surgery also has risks. At present, patients have two main concerns about myopia surgery:
First, whether there will be eye lesions after surgery. At present, the corrective surgery promoted in clinical practice is ocular surface surgery, which does not affect the intraocular structure, so it will not cause fundus lesions such as glaucoma and cataract. However, in order to avoid accidents, patients with eye diseases are not recommended to undergo myopia surgery.
Second, whether there will be a rebound after surgery. This is related to the individual's eye habits, and if the patient continues to use electronic products such as mobile phones and computers for a long time after surgery, there is still a possibility of myopia again. However, the doctor said that even if the vision regresses, it will basically not return to the preoperative level of myopia.
All in all, the safety of myopia surgery is closely related to preoperative examination and evaluation, intraoperative operation, postoperative care, etc., and patients must do their homework before surgery. If the patient decides to have myopia surgery, he must choose a regular hospital and doctor, and do not be greedy for cheapness.
Who can have myopia surgery?
In order to guarantee the safety of myopia surgery, patients must meet three conditions:
First, the patient is at least 18 years old. Generally speaking, adolescents under the age of 18 have incomplete development of the eyeball and cornea, and their refractive power is not stable enough, while most of them have little change in eye development and myopia in adulthood. Therefore, it is safer to have surgery as an adult.
Second, the patient's myopia is stable. At present, the myopia surgery on the market is mainly corneal laser surgery, which is performed on the corneal tissue, and the thickness of the patient's cornea is required to withstand the amount of myopia correction. If the patient's myopia is too high, or the cornea is too thin, the cornea cannot withstand the amount of myopia correction, and the risk of surgery will increase.
Thirdly, the patient has no disease in the eye. For patients with eye diseases, infections are likely to occur during surgery, and uncomfortable symptoms such as acute conjunctivitis, keratitis, dacryocystitis, corneal ulcers, etc.
Precautions before and after myopia surgery
The success of myopia surgery is closely related to the patient himself. The preparation and care of patients before and after myopia surgery has a significant impact on the outcome of the surgery.
First of all, the patient needs to undergo a rigorous examination before the surgery. Doctors need to conduct a rigorous examination of the patient and make a comprehensive analysis and judgment. For example, whether the corneal thickness is sufficient, whether there is keratitis, dry eye, whether there are underlying eye diseases such as glaucoma, fundus disease, etc.
There are some special points that need to be paid attention to in myopia surgery: patients should try not to wear eye makeup one week before surgery, patients who usually wear soft contact lenses need to take off their lenses for more than two weeks before surgery, patients who usually wear hard contact lenses need to take off their lenses for more than one month before surgery, and patients who usually wear orthokeratology lenses (commonly known as "OK lenses") should stop wearing them for more than three months before surgery.
Secondly, patients require strict care after surgery. Three days after myopia surgery, patients should pay attention to avoid unclean water entering their eyes and avoid irritation of chemical ingredients such as facial cleanser and shampoo when performing personal hygiene, so as to reduce the risk of infection after surgery. Second, patients should be careful not to squeeze and rub their eyes too hard, as displacement of the corneal flap may occur in the case of surgery with a corneal flap. It is generally recommended that patients minimize their exposure to electronic screens for about a week after surgery. After that, patients should also maintain good eye hygiene habits and pay attention to the combination of work and rest. If the patient does not pay attention to eye protection after myopia surgery, plays games and watches TV frantically, there will still be a risk of recurrence, excessive eye use will cause eye fatigue, and in severe cases, there will even be fundus bleeding, increased intraocular pressure and other symptoms.