True myopia
True myopia refers to myopia that still exists after examination with ciliary muscle paralyzing agents, and is fundamentally different from pseudomyopia.
1. What is true myopia?
Myopia is a state in which the eyes are clear near, but not clear far, i.e. they can only see near, not far. Children and adolescents are studying at school, reading, writing and other near work for a long time, looking at near objects, the eyes have to use the adjustment function, that is, the ciliary muscle in the eye to contract, long time near work or improper overuse of the eyes, such as reading novels, playing video games, watching TV, etc. can make the ciliary muscle continue to contract, in a state of spasm, when looking at the distance should be relaxed, at this time also can not relax, has been If there is no pathological change in the fundus, it is called pseudomyopia, also called regulatory myopia; if there is pathological change in the fundus, it is called true myopia. True myopia can be divided into: regulatory true myopia, axial true myopia, refractive index true myopia, curvature true myopia, and many others.
2. Clinical characteristics of true myopia
The main clinical characteristics of true myopia are: the degree of myopia is mostly medium and high myopia, the occurrence and development time is longer, and the appearance of the patient’s eye is different degrees of ectropia. True myopia is difficult to self-adjust and recover.
3. Causes of true myopia
Myopia is a type of refractive error. It is a condition in which distant objects do not converge on the retina and form a focal point in front of the retina, resulting in visual distortion and blurring of distant objects.
The cause of true myopia is still not clear, but the accepted view is that myopia is caused by a variety of factors. The specific causes can be divided into two types: internal and external.
Exogenous causes are mainly environmental factors: this is mostly seen in people who work in writing or other close work, and myopia is also more prevalent among teenage students, and its prevalence increases significantly from the fifth and sixth grades of elementary school, a phenomenon that indicates that the occurrence and development of myopia is very closely related to close work.
The internal causes of myopia include genetic factors and developmental factors. Genetic quality means that myopia has a certain genetic tendency, and this is especially true for high myopia, where patients with genetic myopia have the disease at an early age, mostly above 6.00D. High myopia is autosomal recessive, and general myopia is a multi-factor genetic disease, so genetics is a factor that triggers myopia.
Developmental factors can also lead to myopia because infants have small eyes, so they are all farsighted, but as they grow older, the eye axis gradually lengthens and develops normally until puberty.
Since high myopia has more complications and can seriously affect visual function, it is recommended that patients with high myopia go to a specialist hospital regularly to have their fundus and intraocular pressure checked to facilitate early detection, diagnosis and treatment.
4. Identification of true myopia and pseudomyopia
Both true and pseudomyopia are characterized by decreased distance vision and good near vision. Pseudomyopia is functional, mostly occurs in adolescents, vision can be reduced within a few weeks or 1-2 months, and can be restored to some extent after proper rest. True myopia is an organic change that cannot be recovered naturally. There are several differential diagnostic methods as follows.
Ciliary muscle paralysis method
In the ciliary muscle paralysis drug to relax the regulation, so that the ciliary muscle relaxation, so that the eye in a static refractive state, and then check the visual acuity and optometry to determine. Use 1% atropine drops, 1~2 times a day for 3~4 days; or 2% postmastropin or 0.5% tropicamide every 5~15 minutes for a total of 6 times. If the visual acuity remains unchanged after pupil dilatation, it is true myopia, and if the visual acuity increases, it is pseudo-myopia; optometry with myopic refraction is true, and without myopic refraction is false. This is recognized as the most reliable method for differential diagnosis.
Cloud method
Let the patient wear +3.0D spherical lens in both eyes at the same time, look at distant objects for 3 minutes, then remove the right lens, immediately check the naked eye visual acuity, visual acuity progress for false, not progress for true; then check the left eye by the same method. This method is not very accurate.
Dynamic examination method
Without dilating the pupil, we first check the distance and near vision of both eyes. Poor distance visual acuity and normal near visual acuity without other eye diseases affecting visual acuity are the differentiating objects. The doctor and patient sit facing each other in a dark room. The patient wears a trial frame with +2.25D spherical lenses placed in front of the left and right eyes. The patient’s eyes were simultaneously gazed at the visual marker on the examination mirror (the reflector was laterally labeled with the word 5 or words with fewer strokes such as large, small, upper and lower, and illuminated with slit light next to the examination mirror); a 33-cm distance synoptic dynamic examination was performed.
The results were determined: the affected eye was true myopia if the radial direction was retrograde. Each radial direction is paraxial or immobile, or one radial direction is paraxial and the other is immobile for orthopia or hyperopia. Because the vision is myopic, it is pseudomyopia; one radial is retrograde and the other radial is compliant or immobile is mixed astigmatism.
Simple identification method
To identify true and pseudomyopia, in addition to the hospital optometry, a simple method can be hung at a distance of 5 meters an international standard vision table, first determine the vision, and then put on 300 degrees of presbyopic glasses, look into the distance, in front of the eyes will slowly appear cloudy scenery, half an hour after removing the glasses, and then check the vision, such as vision enhancement, can be considered as pseudomyopia; such as vision remains or instead of declining, you can follow this method once a day. Repeat this method once a day for three consecutive days, and if your vision still does not improve, you can be sure that it is true myopia.
Pseudomyopia is generally due to prolonged close work, poor eye posture, reading on a table, lying in bed or in a volatile carriage; too strong and too weak light, etc. so that the eye ciliary muscle is often in a state of tension and fatigue, resulting in vision loss. If proper rest or atropine drops are used to relax the paralyzed and spastic ciliary muscle, vision can be restored. If your eyesight is below 0.8 and your myopia exceeds 100 degrees, you must wear glasses, otherwise your myopia will get deeper and deeper.
5, true myopia prevention methods
(1) Text method
A stiff head or stiff shoulders will worsen blood circulation and indirectly lead to the decline of eye function. Using the head and neck, which is a combination of head movement and point-of-view movement, can naturally restore the above-mentioned healthy functions.
Training essentials: In a light mood, spread your feet shoulder-width apart and let your shoulders relax; gaze into the distance and shake your head to write. You can describe any article you like; your eyes should match the activity of your face, move the point of view and do it for 20 minutes; make sure to match the rhythmic activity, you can put some music, and naturally you can do it in a relaxed atmosphere.
(2) Long-distance running method
Exercise foot strength can also strengthen the eyes. As the saying goes, fatigue starts from the feet and eyes; likewise, aging and fatigue both start from the feet and eyes. The symptoms of fatigue tend to appear in the eyes and feet. Whenever the feet feel tired, the eyes will be tired too. And vice versa. This interrelationship allows us to incorporate the long-distance running method into the overall training system.
(3) Hot and cold method
This is a method of alternating hot and cold towels on the eyes, which is good for eliminating eye fatigue, promoting blood circulation, stimulating the eye muscles and easing the stiffness of the external eye muscles, and can achieve the purpose of refreshing the eyes, revitalizing the eye cells and enhancing metabolic functions.
(4) Patching method
True myopia is prone to eye fatigue, and relieving eye fatigue is also an important factor in preventing the deepening of true myopia. Bright Vision eye patch can effectively promote eye blood circulation, eliminate eye fatigue, so that the eyes in a short period of time to get a better recovery. The unique pure Chinese medicine preparation can directly act on the nerve tissue in the eye 2mm, activating the nerve of the eye tissue, which has a better auxiliary treatment effect on myopia, farsightedness and amblyopia.
Modern ophthalmic medical research shows that: by supplementing the eye, improving eye microcirculation, enhancing eye immunity and antioxidant capacity, and promoting eye tissue metabolism, it can effectively eliminate the causes of many eye diseases, thus protecting eye health to the greatest extent.
Training method: prepare two towels: one towel soak hot water to make the towel hot, the other covered in an ice pack or first refrigerated (to wet paper towels can also be); sitting, standing, lying posture is not limited, relaxed body and mind, eyes closed; first fold the hot towel into the appropriate size, covering the eyes for 3 to 5 minutes, and then replaced with a cold towel, about 2 to 3 minutes clock. Alternating 2 to 3 times, the temperature to the eyes can accept as appropriate. Do this 2 to 3 times a week. It should be noted that: eye inflammation, eyelid redness, keratitis, long needle eyes, pain or fever can not be hot compresses.
6, true myopia wearing glasses precautions
Wearing myopia glasses is mainly to correct vision and can clearly see objects at a distance. In order to keep the ciliary muscle of the eye to maintain a certain adjustment ability, for patients with low myopia, it is better to take off the glasses, that is, wear glasses when looking at distant objects and not wear glasses when looking at near objects. However, if you wear more than 300 degrees of glasses, it is best to insist on wearing glasses all the time. In principle, the only way to avoid aggravating myopia is to maintain a clear vision.
(1) Correctly wearing glasses will not make the prescription deeper
There is no direct relationship between the development of myopia and the wearing of glasses. Myopia patients wear the right glasses, pay attention to eye hygiene, myopia will stabilize at a certain level. However, if you think that everything will be fine with glasses and you don’t pay attention to eye hygiene, you will continue to keep your eyes in a state of long-term fatigue, which will lead to vision loss and myopia deepening. In addition, wearing inappropriate glasses, such as: no optometry or inaccurate optometry, the prescription is too large, will increase the burden on the eyes, so that vision loss, the degree of deepening.
(2) Wearing glasses for a long time after prescription
The normal wearing glasses suffer from myopia at the same time has been diagnosed as true myopia, the degree in the 100 above, should wear suitable myopia glasses to correct. Once you have glasses, you should wear them except for washing your face and sleeping, because after wearing the right glasses, myopic patients are in the state of positive vision, and the adjustment and convergence functions are restored to their natural relationship. Wearing glasses is not only to improve vision, but also to read and work at an appropriate distance, so that there is a normal coordination between the regulation and convergence functions of the eyes, to avoid eye fatigue.
7.Treatment measures for true myopia
True myopia, once formed, is irreversible and is an organic change in the eye. The anterior and posterior axes of the eye become longer, and external objects are imaged in front of the retina through the refractive system of the eye, and there are no clear objects on the retina. This organic change cannot shorten the eye and change the refraction by any method other than surgery, which is why myopia is difficult to cure. Once true myopia is formed, the situation is the same whether it is high myopia or low myopia.
(1) Lens correction
Before prescription lenses, the first step is to find out the true degree of myopia by examining the shadow of a difficult light. For adolescents, optometry should be performed under ciliary muscle paralysis to control the effect of regulation and exclude pseudomyopia. The principle of prescription lenses should be the same as the lowest degree lenses that can correct myopia to the best visual acuity. Generally, myopic eyes below 6.00d should be fully corrected and worn frequently; highly myopic eyes should be fully corrected to obtain better vision, but often cannot tolerate it, so they have to reduce the lens prescription (generally between 1.00d and 3.00d) to be able to maintain comfort and binocular vision function.
(2) Corneal contact lenses
Wearing contact lenses can increase the visual field, have a better cosmetic effect, and can make the refractive difference between the two eyes significantly reduced, so as to maintain binocular vision function. Youth myopia, not only can contact lenses increase visual acuity, but also can compress the cornea to prevent the continued development of myopia. But must pay attention to cleanliness and hygiene, disinfection maintenance and frequent replacement as required.
(3) Telescope type glasses
Patients with very high myopia or macular lesions can often read or do near work with telescopic glasses. The magnification of these glasses is 1.8 times, so it can enhance the distance vision by 2% to 3.5%, and the near vision can be enhanced by up to 5 times. Because the field of vision is too small, they cannot be used when traveling.
(4) Radial keratotomy
This method was first tried by Soviet scholar kranov (1970). It has now been reported in several places in China. The method is to make 8-16 radial incisions between the central corneal 3-5 mm away and the corneoscleral edge, with an incision depth of 0.36-0.50 mm. After the corneal surface is cut, the corneal curvature is flattened, thus reducing its myopia. It is generally believed that 3.00d myopia can be corrected. Because the long-term results of this method are still difficult to be sure, and to be strictly selected to determine the indications and contraindications, and the possibility of surgical complications. Therefore, it is difficult to be universally implemented.
(5) Scleral shortening
This method is the most commonly used surgical treatment for high myopia with reliable results and has been commonly used.
(6) Corneal abrasion
The method is to use specially designed instruments to make lamellar resection from the center of the cornea. The removed corneal piece is treated with low temperature and then ground on a very fine lathe to achieve the required refractive power and then sewn back to the original location to correct high myopia, but the surgery is extremely complicated and dangerous, so it is difficult to promote.
(7) New Rare Tablet Treatment
Myopic patients are generally lack of chromium and zinc, myopic patients should eat more foods that contain more zinc. Foods such as soybeans, almonds, nori, kelp, mutton, yellow fish, milk powder, tea, meat, beef and liver contain more zinc and chromium and can be increased in moderation. It is best to take protein zinc, such as Xin Rui Bao tablets, for zinc supplementation.
(8) Visual aids
Any kind of device or equipment that can improve the mobility of a person with low vision. It has a certain effect on improving the vision of low vision, and can enable them to maintain their independent living ability.
Vision aids are divided into optical vision aids, non-optical vision aids, non-visual aids or devices, and high-tech vision aids, and there are many kinds of them. Such as head-mounted binoculars, color filters to enhance contrast, closed-circuit television aids, etc.
8.Food therapy for true myopia
True myopia patients should eat less high-sugar food, too much sugar, will make the blood to produce a certain amount of acid, acid and salts in the body, especially and calcium phase neutralization, reduction in the blood caused by a reduction in blood calcium, will affect the toughness of the eye wall, so that the eye axis elongation, and promote the occurrence and development of myopia. To prevent true myopia, it is important to choose foods that replenish the nutrients necessary for the ciliary muscle and sclera in the eye, increase the muscle strength of the ciliary muscle, and restore its inherent function; strengthen the toughness of the sclera, enhance its resistance to the outside world, and prevent its continued expansion. The following nutrients can be supplemented.
(1) Vitamins
Vitamins are necessary to maintain normal growth and development, and play an important role in regulating the physiological functions of the body. Patients with true myopia are treated with vitamins A, B1, B2, D, C and E because these vitamins can improve the nutrition and metabolism of the retina, optic nerve and other tissues in the eye, and have a role in enhancing the toughness of the sclera and the muscle strength of the ciliary muscle. Vitamin D can promote the absorption of calcium and phosphorus and maintain the balance of calcium and phosphorus in the body, so children should be supplied with sufficient amount of calcium and vitamin D. Vitamin cannot be synthesized in the body and must rely on food supply, animal liver, dairy, eggs, cod liver oil and other vitamin content is high, fresh fruits contain a lot of vitamin C, beans, peanuts, etc. also have a certain content.
(2) Protein
Protein is the basic material for human life activities, and consists of more than 20 kinds of amino acids. In terms of scleral tissue, it can become the eye against the tough shell, although the sclera has a certain degree of toughness, such as poor resistance and then subject to the influence of external forces. It will be forced to stretch, so that the eye gradually become longer, partial food, picky food is not good for the health, more detrimental to true myopia. Such as fish, meat, milk, eggs have rich protein.
(3) Foods that benefit the liver and kidneys
Chinese medicine believes that the cause of myopia, mainly due to liver and kidney deficiency, qi and blood loss, so the treatment can be used with liver and kidney food and drugs. Foods such as meat, eggs, liver, kidney, crucian carp, yellow fish, cuttlefish, tamari, sea cucumber, shrimp, snapper, as well as cinnamon, lychee, grapes, walnut meat, mulberry, jujube, etc. have the effect of nourishing the liver and brightening the eyes.
(4) Calcium and phosphorus
Calcium and phosphorus are the main components of the sclera and their content is high, which plays a major role in enhancing the toughness of the sclera. At the same time, vitamin D should be fully supplied to promote the absorption and utilization of calcium. This has a role in enhancing development and preventing myopia. Foods such as beef bones, pork bones and other animal bones are rich in calcium and are most absorbed and utilized by the body. Other foods such as dairy, bean products, clams, crabs, shrimp, eggs, capers, rape, peanut rice, dates and other calcium content is also high; and milk, eggs, fish, meat, vegetables, coarse grains and purple cabbage, beans, walnut meat, pumpkin seeds and other food phosphorus content is relatively high.
(5) Zinc and chromium
Zinc and chromium are also essential trace elements, especially zinc has more role in the eye tissue, myopic patients are generally lack of zinc chromium, so it is necessary for them to supplement the food containing zinc and chromium. Such as soy, oat flour, almonds, nori, kelp, lamb, steak, yellowtail, sea slug, oyster, milk powder, cocoa powder, tea, etc. contain more zinc; yeast, beef, cereals, meat, liver and cheese, etc. contain more chromium. It can be taken electively.