The treatment of myopia can be divided into surgical therapy and non-surgical therapy.
(1) The best treatment for myopia is to wear a suitable pair of glasses.
The distance vision of patients with myopia has been reduced to varying degrees. The scenery several meters away is blurry. When going to a shopping mall, it is difficult to see the goods and price tags on display; when walking on the road, it is difficult to distinguish. An acquaintance walking across the street did not say hello, and was considered to be putting on airs and ignoring others; students misread the exercises on the blackboard and did their homework incorrectly. All these make the myopic person miserable. The only way to get out of this hazy world is to wear glasses. However, some patients with myopia would rather not be able to see things in the distance and squint
than wear glasses. The reason is that it is inconvenient for young people to wear glasses because they are afraid of bumping and falling. Some people think that wearing glasses is unsightly and hinders their appearance. I am afraid that after putting on my glasses, the prescription will get worse. I don’t want to take them off again. I put the glasses in my pocket and only wear them when I look into the distance. In fact, this idea is incorrect. People with myopia cannot see distant objects clearly because the parallel light entering the eye cannot focus on the retina. Although you can see things at close range clearly, if your eyes are too close to the book when studying, it can easily cause eye fatigue. Children with myopia may become inactive, have difficulty concentrating in class, cannot see the blackboard clearly, and may suffer poor academic performance, and sometimes may develop strabismus. If you wear a suitable pair of myopia glasses, you can move the image in front of the retina backward so that it falls right on the retina, so you can see things clearly immediately. This will bring great convenience to work or study, why not? As for the inconvenience and unsightliness of wearing glasses, these concerns should be dispelled. The purpose of wearing glasses is to correct vision defects and reduce eye fatigue. Once you wear them for a few days, you will get used to them, and there is nothing unsightly about them. Will my myopia become worse after wearing glasses? We say generally not. Whether myopia develops or not has nothing to do with wearing glasses. It is true that some people who suffer from myopia have worsened their myopia after wearing glasses for a while, and they have to re-opt for glasses. What is the reason? Some people feel that everything is fine after getting glasses, but when writing or reading, they are still very close, do not pay attention to vision hygiene, read for too long, or read while lying down or walking or reading in a place with insufficient lighting, etc. After a long time, It also causes visual fatigue and the degree of myopia continues to increase. Some young people regard wearing glasses as a burden, wearing them for a while, not wearing them for a while, wearing them when they are happy and not wearing them when they are unhappy, or only wearing them when looking into the distance, which puts their eyes in an unstable state of adjustment. The degree of myopia gradually deepens. There are also people who have not undergone mydriatic optometry or the optometrist’s inexperience, so the glasses are inappropriate. Some people just buy a pair in the store or use other people's glasses to wear. Even after wearing the glasses, they can sometimes barely see clearly, but it cannot last long. Over time, the eyes will feel sore and uncomfortable. Not only does it not improve vision, it actually worsens myopia. Therefore, people with myopia must go to the hospital for a dilated optometry or ask an experienced optometrist to get a suitable pair of glasses, which they must wear all day long except when sleeping and washing their face. Remember never blindly borrow someone else’s glasses.
How can I get a pair of accurate and comfortable glasses?
Teenagers suffering from myopia must go to the hospital to check their vision and have their pupils dilated and refracted when wearing glasses. Mydriatic refraction, also known as objective refraction, is the application of drugs (such as 2% homatropine, 1% atropine eye drops, etc.) to completely paralyze the ciliary muscle, dilate the pupil, and lose the adjustment effect. This eliminates the interference caused by the adjustment effect and the pseudomyopia component caused by it, and determines the refractive status of the eye objectively and accurately. Then, the spectacle lenses are ground according to the spectacle prescription determined by optometry, and the ground lenses are equipped on the pre-selected spectacle frames. Usually, a re-examination will be conducted at a certain time after the dilated eye examination. Observe the diopter measured by objective refraction for any abnormal discomfort such as dizziness, nausea, blurred vision, deformed vision, or unsteady walking after wearing the lens. Through re-examination, the objective mydriatic refraction results and the subjective post-examination results are organically and consistently combined to ensure the high quality of glasses fitting to the greatest extent, thereby achieving the best vision correction effect.
Some young people are unwilling to have their pupils dilated for optometry, fearing that their eyes will be uncomfortable after dilation and they will not be able to see close things clearly. In fact, this worry is unnecessary. Pharmacologically, the drugs used for mydriatic optometry (such as atropine, homatropine, etc.) are anticholinergic drugs.
Its effect is to relax the pupillary sphincter and cycloplegia, which is manifested as pupil dilation and accommodation paralysis. The effect of this drug is only temporary. As long as it is no longer used, the paralysis of the drug will disappear naturally after a certain period of time. . If you do not use mydriasis refraction, due to the adjustment effect of the ciliary muscle and lens, you may detect excessive power or pseudomyopia. Therefore, young people with myopia should have mydriasis refraction and choose appropriate myopia glasses. Only when the following conditions exist:
(1) If the examination reveals that the anterior chamber is shallow, the intraocular pressure is high, or the upper limit of the normal value, and patients are suspected of having glaucoma, they should ask for a detailed history and make a clear diagnosis before proceeding. Optometry. Patients with glaucoma are absolutely contraindicated in using mydriatic refraction.
(2) For severe lens, vitreous opacities, and corneal leukoplakia, due to the difficulty of examination, dilated refraction is meaningless.
(3) For severe pupillary synechiae, the pupil cannot dilate normally even after applying mydriatic drugs, and there is no need for mydriasis refraction.
(4) People over 40 years old generally no longer undergo dilated optometry due to the weakening of ciliary muscle adjustment ability.
At present, the main material for making spectacle lenses is optical glass, also called optical spectacle lenses. In addition, there are optical resin spectacle lenses.
Optical glass has the following advantages
(1) High light transmittance. The light transmittance can reach 92%. If one or more layers of magnesium fluoride are plated on the surface of the lens, the light transmittance will increase. Transparent film, the light transmittance of the lens can reach 99.2%.
(2) Absorb ultraviolet rays to avoid damage to the eyes from ultraviolet rays.
(3) Chemical stability, resistant to corrosion by acids, alkalis and other chemical substances.
(4) The refractive index is constant and accurate. The refractive index is 1.523, constant and accurate, and the diopter after processing is accurate.
Optical resin is characterized by its light weight, hardness close to glass, and a refractive index of 1.490. The refractive index of the new high-refractive index thermosetting resin is 1.600, and the surface is coated with a super-hard film and a non-reflective multi-layer film to enhance wear resistance, the light transmittance can reach 98%, and it can block ultraviolet rays. Spectacle lenses made of optical resin are not easily broken and damage the eyeballs, and are very safe. They are now widely used. Crystal is hard, wear-resistant and has good thermal insulation, but its ultraviolet absorption performance is worse than that of optical glass, and its light transmittance is also poor. It is not an ideal material for making spectacle lenses, nor is it an eye-catching product.
The photometry of the spectacle lens layer must be processed accurately, and the lenses must be ground to be consistent with the prescription. The diopter error should generally not exceed the national standard of 0.04D-0.09D issued by the Ministry of Light Industry. The optical center distance of the lenses of both eyes must also be consistent with the interpupillary distance of both eyes.
What everyone sees and wears every day are glasses that are placed on the bridge of the nose or clipped to the ears, which is very inconvenient. There are also some people who have greater myopia in one eye and less in the other eye; or they have had cataract surgery in one eye and the other eye is normal. Because the anisometropia of the two eyes is too large, one eye sees something large and the other eye sees something too small, and the visual center cannot fuse them together. Therefore, ordinary glasses cannot be worn. In recent years, a kind of glasses that cannot be seen when worn, commonly known as contact lenses, has emerged. It is a lens worn directly on the surface of the tear layer of the cornea. There is a liquid lens composed of tears between the cornea and the lens. In this way, a new refractive system is formed by the lens, liquid lens, cornea and other refractive media of the eye. Medically called contact lenses.
Contact lenses can be divided into hard contact lenses and soft contact lenses according to the material of the lens. Hard contact lenses are made of organic glass mainly composed of methyl methacrylate. They are hard and not easily deformed. Suitable for correcting high astigmatism and keratoconus. Its disadvantage is that it has poor breathability and cannot penetrate oxygen, carbon dioxide, moisture and metabolic substances, making it uncomfortable to wear. Soft contact lenses are made of methacrylic glycolic acid or silicone rubber. They are soft, have good air permeability, and can absorb moisture. They are soft and comfortable to wear. They can be used to treat corneal diseases, but they are easy to change. The shape is not suitable for astigmatic eyes.
According to the wearing method, it can be divided into long-wearing type and daily wearing type. Wearing contact lenses overnight or for more than two consecutive days is considered long-wearing type, including weekly wearing type, monthly wearing type and even no-take-off type. If long-wear lenses are worn continuously for many days before being removed and cleaned once, proteins and other substances in tears will be deposited on the lenses, eventually causing permanent cloudy spots and affecting the clarity of the lenses. What's more serious is the accumulation of bacteria, which can easily lead to infectious keratitis. In view of this, long-term wearing is no longer recommended.
The daily wear type should be worn continuously for no more than 14 hours.
It must be removed every night for necessary cleaning, disinfection and proper storage, and then worn again on this day. Because of the daily wear method, the lenses are removed and cleaned every night, so there will be no permanent cloudy spots on the lenses. Daily cleaning and disinfection greatly reduces the possibility of infectious keratitis. Therefore, day-wearing must be adhered to, and long-term wearing is not advisable. Contact lenses have advantages that ordinary glasses do not have and solve problems that ordinary glasses cannot solve. Since the contact lens is closely attached to the cornea and can rotate with the rotation of the eyeball, no matter which direction the eyeball turns, light always enters the eye through the center of the lens, eliminating the defects of the prism effect and oblique astigmatism produced at the edge of ordinary glasses. . Contact lenses are ground according to the curvature and diopter of the patient's corneal surface. They adhere closely to the cornea, so that the lens, tear layer and cornea form a new refractive medium and participate in forming a complete optical unit. The surface of the lens The curvature can be adjusted at will according to the refractive requirements. It replaces the irregular curvature of the corneal surface, effectively eliminates irregular corneal astigmatism, and narrows the difference in image size between the two eyes. Because the contact lens is close to the cornea, the distance from the center of the eyeball is shortened. After the light passes through, the image formed on the retina is similar to that without glasses, and things will not be enlarged or reduced. It avoids the shortcomings of ordinary glasses and is most suitable for those with large anisometropia in both eyes or aphakia in one eye. Contact lenses are thin and light and are adsorbed on the surface of the cornea, making them much more convenient than thick and heavy lenses for high myopia. In addition, it brings great convenience to people with special needs (such as actors and athletes). Precisely because contact lenses have so many advantages that ordinary glasses do not have, their application range is much wider than ordinary glasses. It is more suitable to wear contact lenses if you have the following conditions:
(1) High myopia, anisometropia of more than 3.00D in both eyes, mixed corneal astigmatism or irregular astigmatism. Especially for some literary and artistic or sports workers, due to professional needs, wearing ordinary glasses will affect their work or competition performance, so they can choose to use contact lenses.
(2) Some people have had cataract surgery in one eye. Due to the large anisometropia, they cannot wear ordinary glasses and can only wear contact lenses.
(3) Soft contact lenses can be used to treat corneal edema, exposure keratitis, and keratoconjunctivitis sicca. Painting the same color as the iris around the lens and keeping the center transparent can eliminate the photophobia symptoms of patients with albinism and iris defects. In recent years, there are also corneal contact lenses specially made for therapeutic purposes. A certain drug is soaked in the contact lens and can be released into the conjunctival sac at regular intervals. This not only reduces the number of times of dispensing the drug, saves the dosage of the drug, but also makes the conjunctiva The capsule always maintains a higher concentration of medicine to achieve better therapeutic effects, such as treating glaucoma, corneal ulcers, etc.
Although contact lenses have many advantages, they also have certain limitations and are not suitable for everyone. There are three taboos when wearing contact lenses.
*Own conditions include entropion, trichiasis, incomplete eyelid closure, dacryocystitis, dry eye, severe trachoma and chronic conjunctivitis, keratitis, diabetes, hypertension, paranasal sinusitis, etc.
*Environmental conditions Wind sand, dust, volatile chemicals and severely polluted environment.
*Personal qualities: People with poor hygiene habits, poor self-care ability, and unable to persist in serious care, such as primary and secondary school students.
Although contact lenses are constantly improving, their chemical properties, comfort and safety have reached ideal levels and are widely used. With the popularization of application and long-term clinical observation, some complications ranging in severity have emerged. Such as corneal damage, conjunctival inflammation, corneal infection, etc.
For many years, curing myopia and taking off glasses has become the urgent wish of the majority of people who wear glasses due to myopia. They look forward to the arrival of the nemesis of myopia and the gospel, and realize their dream of taking off their glasses. It is under this circumstance that some treatment devices and drugs that cater to the desire of parents and teenagers to take off their glasses have come into being with an efficiency of over 95%.
Methods that have been tried to treat myopia include acupuncture, plum blossom acupuncture, ear acupuncture, electroacupuncture, low-frequency current method, ultrasound method and acupoint laser irradiation method. These therapies have certain effects in preventing myopia and treating pseudomyopia, but they have no definite effect on true myopia.
In recent years, countless medical staff and pharmaceutical experts engaged in ophthalmology have conducted useful research on the treatment of myopia, and have formulated some drugs for the treatment of myopia, such as Summer Eye Drops, 1% Dimazole Eye Drops,
Salvia eye drops, safflower eye drops, myopia No. 1, No. 2 eye drops, etc. These eye drops can relieve ciliary muscle spasm to a certain extent and have certain effects on mild myopia, especially adolescent myopia and pseudomyopia. The vision of some patients can be improved, but the effect is not stable. In short, the effect of drug treatment of myopia is still unsatisfactory. As for magnetic therapy glasses, vision care devices, vision care devices, vision correction devices, physiotherapy mirrors, eye masks, magic glasses and other myopia treatment devices, there are many varieties
and their advertisements are frequently seen in various publicity media. The words are extremely exaggerated, and what's more, some are even titled as national patents, which is really tempting. As a result, many people with the mentality of giving it a try have lost money and time, and in the end have to wear glasses.
(2) Surgical treatment of myopia
Indications for surgical treatment of myopia: Age over 18 years old; myopia diopter 2.50D or above; wear glasses to correct vision; wear glasses No need for glasses; no active corneal lesions or keratoconus; no history of diabetes or collagen disease.
As mentioned before, myopia can be treated with acupuncture, drugs and other methods, but the more reliable treatment method is still to wear myopia glasses. However, whether wearing frame glasses or contact lenses, there are some shortcomings that are difficult to overcome. Can vision be corrected surgically? In the 1980s, some advanced and developed countries in the world successively carried out the surgical treatment of myopia - radial keratotomy, or PRK for short. This surgical method originated in Japan. Later, ophthalmologists from the former Soviet Union, the United States and other countries improved and perfected the surgical methods and instruments, which greatly improved the accuracy of radial keratotomy. Improved and accumulated a lot of clinical experience to achieve better treatment results. Especially for young adults over 20 years old, the success rate of surgery for mild and moderate myopia is over 95%. For high myopia of 6.00D-10.00D, most people can take off their glasses, and it can also be used for high myopia of 10.00D or above. Reduce myopia. It also has a certain effect on myopia and astigmatism. Radial keratotomy opens up a new way to treat myopia. Myopia surgery started relatively late in my country. Around the mid-1980s, when radial keratotomy was introduced to my country, it became popular all over the country. Hospitals of all sizes began to use it, including inviting Russian foreigners to perform the surgery. Due to the lack of surgical instruments and insufficient clinical experience, the postoperative correction of vision is not ideal and there are many complications. In recent years, some large hospitals in my country have purchased advanced foreign surgical instruments—gold diamond knives. This kind of knife is not only sharp, but also has a thin blade (only 0.1 nanometer), and has a scale display to adjust the depth of the cut at will. Postoperative corneal scars are thin, uniform in width and depth, and less likely to cause irregular astigmatism. Therefore, it is very popular among myopia patients, especially those with high myopia.
In addition to radial keratotomy, many new methods of surgical treatment of myopia have appeared abroad, and some large hospitals in China have also successively carried out these surgeries.
(1) Superficial keratoscopy: Using allogeneic cornea, it is frozen and ground to different refractive powers on a special machine tool, and then the lamellae are separated in the central part of the patient's cornea, and the special corneal lens is It is embedded in the corneal lamellae and sutured around to achieve the purpose of correcting myopia.
(2) Keratomileusis: Use your own cornea to remove the lamellae from the center. The removed corneal tissue is treated at low temperature to harden it and is ground as needed on a fine lathe. , after reaching the required diopter, then sew it back to its original position.
(3) Laser keratotomy: Use excimer laser (wavelength 193 nanometers) to perform radial corneal incision. The incision is made more precise and precise, the correction effect is better, and surgical complications are greatly reduced.
(4) Posterior scleral reinforcement: This surgery uses medical silicone sponge, allogeneic sclera or fascia lata as protective reinforcement materials to strengthen and fuse the posterior sclera to support the posterior pole of the eyeball. , preventing the progressive expansion of the posterior pole and the progressive elongation of the axial length of the eye, and reducing the degree of myopia to a certain extent. At the same time, new blood vessels are formed after surgery, which enhances blood circulation in the choroid and retina, excites visual cells, activates bioelectricity, and improves visual acuity.
This surgery is suitable for controlling the progressive axial lengthening of the eyeballs with high myopia, especially for adolescents with high myopia whose axial length exceeds 26 mm and the myopia diopter deepens and develops by more than 1.00D per year.
Surgical complications Myopia surgery solves the problem of wearing glasses for high myopia to a certain extent, and also meets the work needs of people engaged in special occupations, and is welcomed by myopia patients. However, no matter how simple and safe the surgery is, it is by no means foolproof. Moreover, myopia surgery is not yet a very mature surgery, and many aspects still need to be improved. At present, the main surgical complications are:
(1) Intraoperative corneal perforation complicated by cataract and bacterial endophthalmitis;
(2) Corneal ulcer, delayed incision healing and corneal endothelium Damage;
(3) Postoperative scars and epithelial cysts cause irregular astigmatism and seriously affect vision;
(4) Residual myopia, anisometropia, astigmatism or over-correction< /p>