It increases every year.
This is due to the increased load on the eyes.
They suffer mainly because of computer monitors and smartphones.
Self-selection of glasses for myopia threatens with health-threatening complications. In case of visual impairment, it is necessary to consult a doctor to choose the most optimal method for correcting refraction.
When vision deteriorates, a person sometimes does not know whether he should buy glasses. This question can only be answered by an ophthalmologist after determining visual acuity. With myopia, negative lenses are prescribed.
There are 3 degrees of myopia:
Glasses are necessary in any case, if a person feels a deterioration in vision in the distance. Even with slight visual discomfort, severe headaches and fatigue appear. And ignoring glasses or lenses contributes to the fact that the patient develops strabismus.
Thanks to the correction of vision, a person will save himself from strabismus, dystrophy of the fundus, retinal detachment and other complications.
Wearing glasses is also necessary for those patients who work at the computer for a long time. Moreover, they are recommended special lenses with a protective coating. They delay harmful blue radiation, which prevents visual fatigue.
Eyeglasses and contact lenses are recommended for vision correction. It is difficult to answer unequivocally which is better - glasses or contact lenses. They have their own advantages and disadvantages that must be considered when choosing a means of vision correction. So, glasses are easy to use, but at the same time they give a slight distortion of vision.
But what if the weather is bad outside or you need to engage in activities associated with the danger of breaking glass or plastic? In this case, contact lenses will help. But wearing them is closely related to the need to comply with the rules of hygiene. Lenses can be easily lost or damaged. In addition, they must be changed frequently, and this entails additional financial costs.
The advantages of lenses are their complete invisibility to others. They provide excellent vision in patients with a high degree of myopia.
Lenses are inappropriate if the degree of myopia is weak. For them, there is no need for constant vision correction, they need to use glasses if they need to see any distant object.
Glasses have their advantages and disadvantages.
Points pros:
At the same time, glasses have some disadvantages:
The relative disadvantage of points is the ability to worsen the appearance of a person. However, this problem is easily solved - you need to be more confident. An optical store employee will help you choose the most suitable frame that emphasizes the dignity of the face and hides its flaws.
Three types of glasses are used to correct myopia:
There are also glasses with bifocal lenses. They are prescribed at the initial stage of the disease, when objects near are clearly visible, and blurry in the distance.
A bifocal lens has 2 parts: one of them has a “minus” part to look into the distance, and a lower one without diopters, so that close objects can be viewed without harm to vision.
Your doctor may recommend photochromic lenses. In the sun, they change their color and become darkened. In the room, they become transparent again. These lenses protect the retina from intense ultraviolet radiation.
When choosing glasses for people suffering from myopia, follow some rules:
During the selection of glasses, negative lenses are placed in front of the person. If at the same time visual acuity increases, this indicates the presence of myopic refraction. The selection starts with a weaker lens. The doctor moves to stronger lenses until the optimal degree of correction is achieved.
The choice always rests on the weaker lens that provides optimal correction.
Before choosing a frame, follow these recommendations:
When choosing a frame, you need to consider the material from which it is made:
The choice of glasses should be associated with the use of medications to relieve eye strain. In addition, it is recommended to subject the eyes to a test visual load in order to understand how certain objects will be seen, what the general sensations will be.
Glasses should only be prescribed by an ophthalmologist. He determines which lenses are needed. If you choose them yourself or incorrectly, it will negatively affect your vision and the state of the body as a whole. Signs that glasses or lenses are not chosen correctly:
If the glasses were chosen in compliance with all the rules, but after some time the described symptoms began to be felt, you need to contact an ophthalmologist. Perhaps the degree of myopia has changed and it is necessary to choose other glasses.
The method of wearing glasses depends on the degree of development of myopia, its progression and other factors. All of them are determined by an ophthalmologist. Persons with a weak degree of myopia can use glasses during visual stress: driving a car, watching TV, learning boards during class.
For people with medium and high myopia, it is recommended to choose two pairs of glasses for work at close range and for distance work. Glasses for constant wear with myopia have a slightly greater optical power.
In order for glasses to be useful, they must be worn correctly. The following rules are recommended:
Glasses require care. The lenses should be wiped with a microfiber cloth using a special solution. No cracks or scratches should be allowed. The glasses are stored in a case.
New glasses take some getting used to. Adaptation can take up to a week, sometimes a little more. In the early days, it is recommended to wear them for only a few hours. addiction will pass much faster if you buy a good frame that will certainly decorate your face.
Myopia is a common eye disease today.
Such a diagnosis is made to almost every third person who turns to an ophthalmologist with complaints of poor distance vision.
In general, this pathology is not dangerous, except for some cases requiring surgical intervention.
Most often, nearsighted people are prescribed lenses of different strengths, depending on the level of development of the problem.
Special glasses focus on the retina, making the picture far clearer.
There is no such thing as "glasses for the treatment of myopia". This accessory only corrects vision and is effective only in direct contact with the eyes.
Often patients ask how to choose glasses for myopia and whether they can be worn all the time. It depends on the degree of development of the disease.
The accessory for the correction of visual function is selected taking into account the degree of pathology and personal preferences of the person.
The need for correction is one of the important issues
However, constant correction is not always required. Sometimes the doctor prescribes glasses to the patient only for those cases when it is necessary to consider something in the distance. For example:
The degree of deviation is an important criterion
With a deviation of up to -1 diopter, glasses are rarely prescribed.
Fact: This degree of myopia is quite safe for a person and does not bring much discomfort.
If they are advised to purchase such an accessory, then only the kind that does not correct vision by 100%.
With a weak degree of myopic disorder, such a correction is not used constantly. It is resorted to only in cases where there is such a need.
Pathology with a deviation from -2 diopters and more requires constant correction. With such myopia, glasses are prescribed for permanent wear.
A person with such vision usually sees poorly not only in the distance, but also near objects.
Often, for such patients, another pair is prescribed:
Interesting: There are also bifocal lenses.
They are made in such a way that the top of the lens is for the distance, and the lower part is for reading and working.
During the examination, it may turn out that one eye does not see well into the distance, and the other vice versa. Then the ophthalmologist recommends lenses that are suitable for.
Important: If the vision is very poor, then myopia glasses will not be able to correct it 100%.
In this case, the patient needs surgery or laser correction.
There is a myth that says that the constant wearing of glasses spoils your eyesight. However, this is fundamentally not the case.
Only improperly selected lenses can spoil the condition of the eyes, from which the muscles get tired.
Often the question arises of which glasses are needed for myopia: plus or minus. Only diverging lenses, which are minus, can make a clear image far away.
The choice of a corrective accessory for the eyes includes several stages:
Modern optics is an opportunity to choose the version of the product that will satisfy individual needs.
Choosing lenses is not an easy task.
Important: The strength of corrective glasses is selected only by a doctor.
Additional characteristics are completely in the power of the patient. There are such models of lenses:
Each person can independently decide which glasses he needs.
If the doctor prescribes the strength of the lenses, then the frame is entirely the choice of the patient.
There are such options:
Doctors often disagree on how to wear glasses.
This question causes difficulties, especially if the degree of myopia is small.
Some say that they look only into the distance, while others say that both into the distance and in front of them.
Important: The main thing is comfort. You need to listen to your feelings.
As soon as tension or discomfort appears, then it is better to remove the glasses.
Some patients complain that the optics constantly fog up, smear with fingers and can be broken.
Because of these and many more factors, people refuse to use this type of correction.
But: This is very harmful. With myopia, a person constantly squints, which causes severe eye strain.
As a result, vision may deteriorate even more.
Today, glasses have become a stylish addition to any look and are in fashion, so do not be shy to wear them.
Greetings, dear readers! For more than a dozen years, disputes have continued on the topic of whether it is necessary to constantly wear glasses with myopia or not. Some believe that optical correction is not needed with a weak degree of this disease, since due to the constant use of additional optics, eye contact with the external environment only worsens. Others, on the contrary, are convinced that eyepieces should be worn even with the slightest impairment of eye perception.
Whose side is the truth on? The participants in this dispute are not only patients, but also doctors. Some ophthalmologists are hesitant to prescribe so-called optical correction to patients with less than -1D myopia. As for the patients themselves, they either completely exclude the wearing of glasses for myopia, or use them periodically. Let's try to figure out what's what.
We all know that the purpose of glasses is to help people with poor eyesight. Thanks to this optical correction, we get the opportunity to see the beauty of the world around us in the brightest colors. The advantages of eyepieces are:
Yes, optical devices will not help get rid of myopia, but they are able to stop its progression and reduce visual acuity.
To begin with, I will say that the need to wear glasses depends on. As you know, there are 2 types of myopia:
When a child is diagnosed with a weak anatomical eyepiece, you can not wear eyepieces, but do not forget that this disease tends to progress, so sooner or later you still have to resort to correction with glasses.
Important! In the case of continuous wearing glasses, a person will no longer be able to get rid of false myopia, so be sure to consult with your ophthalmologist on this topic.
With accommodative myopia, things are somewhat different. With this type of pathology, it is harmful to constantly wear eyepieces, as this contributes to even greater relaxation of the eye muscles. Continuous wearing of glasses leads to a complete correction of the organs of vision, that is, the muscles of the eyes do not need to work. Accordingly, they will receive less load and will not be able to function at full capacity.
For close work, a second pair of glasses or bifocal lenses are often prescribed. A feature of such lenses is that they have 2 optical zones: the upper half of the glasses corrects distant perception, and the lower one improves near vision.
When the degree of myopia is high (more than -6 D), patients, especially children, should wear a special eye device daily, except for visual work at a distance of no more than 40 cm.
With such a low perception, a complete correction is often impossible, so the eye doctor prescribes a "tolerability" correction. He prescribes those devices in which a person will be as comfortable as possible, and not those that 100% correct vision.
Important! Patients with high myopia are mainly prescribed several types of glasses: for regular use, for reading, for working at a computer, etc.
When selecting optical devices for myopic patients, the ophthalmologist first determines the degree of vision loss. For this, the following procedures are carried out:
I recommend that you watch an interesting video where people on the street are asked “is it harmful or not to wear glasses all the time”? Interestingly, the opinions of passers-by diverged. But the ophthalmologist claims that with the constant wearing of glasses there is no harm, on the contrary, there are only pluses. Happy viewing!
The use of glasses for this disease is the simplest and most affordable way to improve vision, which does not cause complications. The choice of special devices for visual 100% vision should be approached with all responsibility, because it depends on how successful the correction of eye contact will be in children and adults.
It is very important to contact a qualified specialist who will select corrective eyepieces taking into account the individual characteristics of the patient's optical system. In addition, we must not forget that it is possible to apply individual treatment, so as not to use the wearing of additional devices in the future. What do you think - is it harmful to wear glasses all the time? Share in the comments, your opinion is important to us. Take care of your eyesight and be healthy, friends!
Reduced visual acuity is not only an urgent medical but also a social problem. Today, a huge number of young and middle-aged people suffer from myopia - a visual defect in which a person does not see well into the distance and cannot clearly distinguish objects that are at a distance. With myopia, refraction is disturbed - the refractive power of the eye. To clearly see an object at a distance, a person has to squint. Therefore, in ophthalmology there is another term for this visual defect - myopia (in Greek "myops" - "squint"). The most common way to eliminate such a pathology of refraction of the eye is to wear glasses for myopia.
In normal vision, rays of light coming from distant objects pass through the eye's optical system and converge into focus on the light-perceiving membrane of the retina. With myopia, the rays are projected in front of the retina, scattered and hit the retina in an unfocused form. As a result, the image is blurred, blurry, fuzzy. Such a visual defect develops due to an excessively strong refractive power of the cornea and lens, or due to an increase in the length of the eyeball, which takes on an elliptical shape. To correct the refractive error of the optical system of the eye with myopia, ophthalmologists select the appropriate glasses for the person.
The refractive power of glasses is expressed in diopters. In the case of the development of myopia, minus (negative) diopters are selected. With an initial degree of myopia (up to -3.0 diopters), glasses can completely restore visual acuity. However, quite often eye doctors recommend wearing them only as needed. Many ophthalmologists believe that the constant wearing of glasses weakens the eye muscles, so myopia will progress quickly.
If the degree of myopia is expressed within 3.0 - 6.0 minus diopters, it is no longer possible to do without glasses. In the middle phase of refractive error, ophthalmologists try to accurately select the diopters of glasses. Their constant wearing allows you to completely correct your vision and save a person from many problems that arise in everyday life.
With high myopia (above -6.0 diopters), doctors recommend wearing glasses one diopter less than the diagnosed visual impairment. Among ophthalmologists, this approach to the selection of glasses is called tolerance correction. The fact is that strong minus lenses of glasses significantly reduce the size of visible objects, which leads to a violation of spatial perception. In this case, one hundred percent vision correction is not achieved, but the person gets rid of increased eye fatigue.
In addition, when selecting corrective glasses of any degree of myopia, the distance between the centers of the pupils of the eyes should be taken into account. When wearing glasses with an incorrectly chosen center-to-center distance, eyes can quickly get tired and dizziness often occurs.
It is well known that when looking at a person, glasses are the first thing that catches the eye. Therefore, from the point of view of aesthetics, one should approach responsibly the choice of frames and lenses for glasses. In particular, for a person with a round face, square glasses are best, and for people with elongated features and a long nose, round glasses are the most preferred choice.
Much depends on the material from which the glasses are made. The plastic frame is not afraid to drop, but if you step on it or accidentally sit down, it breaks in half. The metal frame is flexible, so it bends easily. On the one hand, this is good (the frame takes the shape of the face), on the other hand, it is bad: it is not always possible to straighten the damaged frame correctly and give it its original shape. It is better to choose plastic or polycarbonate lenses, since glass lenses are heavy: glasses will slide off the face.
With the current level of industrial production, it is not difficult to acquire good glasses for myopia. The main thing: the correct selection of diopters and comfort when wearing glasses!
26-10-2011, 05:54
In the myopic eye, after refraction in its optical system and with complete rest of accommodation, only divergent rays are collected on the retina, i.e., emanating from some point located in front of the eye at a finite distance. This distance from the anterior main point of the eye to the further point of clear vision will characterize the degree of convergence of the rays incident on the eye, and, consequently, the degree of myopia.
Parallel rays after refraction in the system of the myopic eye are collected in front of the retina, i.e., the main focus of the optical system of the myopic eye does not coincide with the retina. The eye will be disproportionate, ametropic, since the length of the optical axis of the eye and the length of the focal length do not correspond to each other: either the refractive apparatus has a shorter focal length than the length of the eye (refractive myopia), or the length of the eye is greater than necessary for a given refractive power of the optical eye systems (axial myopia). Two more types of myopia are distinguished: myopia of mixed origin, in which the refractive error is due to a deviation both in the length of the axis and in the refractive power of the eye, and combination myopia, depending on a peculiar combination of essentially normal elements of the optical apparatus of the eye. At high degrees of myopia (above 6.0 D), axial myopia prevails, and at low and moderate degrees - combination myopia.
According to Gulstrand's diopter calculus, the degree of myopia is equal to the reciprocal of the distance from the anterior main point to the further point of clear vision, and is indicated by a fraction with a unit in the numerator, and the distance to the further point in the denominator, expressed in meters or centimeters.
M = 1/-R D,
where M is the degree of myopic refraction, R is the distance to the further point of clear vision (since this distance is measured from the eye to the left, it will be with a minus sign).
The expression for a negative lens that corrects the degree of myopia also coincides with this expression, since the denominator will be the rear focal length of the lens, and the rear main focus is in front (to the left) of the rear main plane of the lens. For example, at a distance to a further point of clear vision of -50 cm (or -0.5 m), myopia will be equal to
If the further point of clear vision is in front of the eye at a distance of -200 cm (or -2 m), then myopia will be
At the same time, the lens correcting myopia in the first case will be 2.0 D with a focal length of -50 cm, and in the second case, the lens will be 0.5 D with a focal length of 200 cm. The focal length of the corrective lens and the distance to the further point of clear visions are identical.
On fig. 27 is a diagram of a myopic eye. Parallel beams join at the main focus of the system F, which is located in front of the retina, and a circle of light scattering a1b1 is obtained on the retina.
On the retina at point M, rays emanating from point R, located at a finite distance in front of the eye, can join. These rays are indicated by a dashed line.
Diagnosis of myopia It is based on the fact that vision improves from placing concave glasses on the eye, while convex ones worsen. The degree of myopia is determined by a negative lens, which makes parallel rays, after refraction, diverge from a further point of clear vision, located in front of the eye and coinciding with the main focus of the lens.
On fig. 28 presented myopia correction scheme. The dashed line denotes those rays that, by refraction in the eye, are connected on the retina at point M. The further point R is in front of the eye and coincides with the main focus of the negative lens AB placed in front of the eye, which gives the parallel rays a direction that coincides with the direction of the rays emanating from the further points of clear vision, and it is precisely such rays that are connected on the retina of the myopic eye.
In determining the degree of myopia, the task is to find such a negative lens, the back focus of which would coincide with the further point of clear vision of the myopic eye. Without correction, the myopic eye cannot have full visual acuity, it is always reduced, and the more so, the higher the degree of myopia.
In practice, when selecting glasses, proceed as follows. To determine the degree of myopia, negative lenses are placed in front of the patient's eye. If at the same time vision improves, then this will indicate the presence of myopia; start with weak lenses and gradually move to stronger ones. The visual acuity improves little by little, until finally, with a certain lens, the highest visual acuity is obtained. If this is achieved with several lenses, then they stop at the weakest. With stronger glasses, we cause hypermetropia, and the eye immediately begins to accommodate in order to better see the signs of the table. Therefore, the degree of myopia is characterized by the weakest negative lens, with which the highest visual acuity is obtained.
After selecting the weakest negative lens for each eye separately, it is recommended to check the vision even binocularly, while reducing the glasses for each eye by 0.25 D or 0.5 D; if the patient has the same higher visual acuity with weaker glasses, then myopia of an equal degree of these glasses should be considered. This is due to the presence of a small spasm of accommodation. With distance vision with parallel lines of sight, it is easier to relax accommodation.
Example. one. Visual acuity of both eyes 0.3; negative lenses improve vision: with lens -1.5 and -2.0 D visual acuity is 1.0. What is the refraction and where is the further point of clear vision?
There is myopia in the degree of 1.5 D, since the weakest glass expresses the degree of myopia. The further point of clear vision is in front of the eye at a distance of -66 cm. R \u003d 1 / -1.5 \u003d -0.66 m (-66 cm). The degree of convergence of divergent rays incident on the eye is 100/-66= - 1.5 D.
Example 2 Visual acuity without correction 0.04. Negative lenses improve vision. Lenses - 6.0, -6.5 D and -7.0 D give a visual acuity of 1.0. What is the refraction of the patient and where is the further point of clear vision?
There is myopia at 6.0 D, since the weakest glass expresses the degree of myopia. The further point of clear vision is in front of the eye at a distance of -16 cm; R \u003d 1 / -6 \u003d - 0.16 m (-16 cm).
Since in myopia the further point of clear vision is relatively small in front of the eye, this distance can be easily determined by a simple measurement with a centimeter ruler. Inviting the patient to read the font No. 5 or No. 6 of the table near Golovin - Sivtsev at an extremely distant distance from the eye, this distance is measured with a ruler.
M \u003d 100 / -22 \u003d - 4.5 D.
This method is simple and convenient, but not accurate, because the patient, when reading fonts at a close distance, somewhat strains accommodation, which enhances refraction, and there is always a danger of determining a higher myopia than it actually is. Therefore, its use is permissible only for the purpose of tentative determination of the degree of myopia.
In reality, the degree of myopia never corresponds exactly to the refraction of the lens by which it is determined, since for this the lens is attached not to the eye itself, but at a certain distance from it, i.e. there is a discrepancy between the lens and the ametropia of the eye, as already mentioned at considering hypermetropia.
The issue of correcting myopia is much more complex and responsible, than the question of the correction of hypermetropia, firstly, because myopia, almost as a rule, progresses; secondly, because myopia, especially of medium and high degrees, very often causes a sharp decrease in visual acuity; thirdly, because myopia, especially a high degree, is often complicated by changes in the fundus, which require not only correction, but also treatment. These changes in the fundus of the eye have long established the view of such myopia not as a simple refractive error, but as a disease. Therefore, the correction of myopia in many cases is not a purely optical event, but also a therapeutic one. In view of the foregoing, with myopia one has to think about prevention aimed at delaying the progression of myopia and preventing its complications, which very often lead to a sharp decrease in vision, and sometimes to blindness.
The purpose of this manual is to present mainly the issues of correction of ametropia, therefore, when solving our problems, we will deal with the prevention of myopia only as necessary, and therapeutic measures will not be included in our task at all, since they relate to other departments of ophthalmology.
Currently, it is generally recognized that the need for a complete correction of myopia is considered.
Incomplete correction is supported by only a few doctors of the old school who believe that accommodation and convergence increase intraocular pressure and thus contribute to the further progression of myopia. But this assumption has not yet been proven by anyone. You have to think it's wrong. Optometrists who adhere to these old views prescribe an incomplete correction (3.0 - 4.0 D less), both for distance and for near, and do not insist on wearing glasses all the time.
At present, there is much more evidence that complete correction is the main intervention that contributes to the treatment of myopia and delay its progression.
Full correction improves visual acuity and thus improves working conditions. Full correction makes it possible to read at a farther distance, therefore, to strain convergence less and use accommodation more (approximately as convergence and accommodation are used in emmetropia).
Sometimes a full correction has to be approached cautiously, introducing stronger lenses gradually, or even abandoning a full correction, taking into account a number of circumstances.
First of all, it is necessary to take into account the inability of a person with myopic refraction to use accommodation. This is especially noted at an older age, if the patient has never worn glasses by the time of the first correction. If such a patient is armed with glasses that completely correct myopia, then. he will not be able to use accommodation, as in emmetropia, even for a very short time. Such a person is accustomed to converge strongly without glasses and almost no accommodation at all, or, in any case, to use accommodation much less than a person with emmetropic refraction with the same convergence. Armed with myopia-correcting spectacles, it should accommodate even slight convergence. The patient will not be able to cope with work at close range with the new relationship between convergence and accommodation. The need for additional tension of the ciliary muscle is unusual for him, and sometimes completely impossible. In youth and with good accommodation, the eye can still cope with such unusual work for him, but at an older age the patient will quickly get tired and, in the end, will refuse to work with glasses, considering the glasses given to him to be incorrectly selected and harmful, unless, of course, , the doctor did not warn when prescribing glasses that you need to get used to the glasses. In such cases, therefore, it is necessary either to teach patients to gradually get used to glasses prescribed for constant wear, or to prescribe weaker glasses for near and gradually move on to glasses that completely correct myopia.
Negative lenses large refractive power, due to their distortion of the perspective and shape of objects, cause very unpleasant sensations in patients who begin to wear such glasses. In an eye armed with such glasses, the images of objects on the retina are reduced; the location of these images changes; in connection with this, the projection of images outwards also changes. As a result, an incorrect assessment of the distance of objects from the eye, their size and shape is obtained, straight lines seem to be curved in an arcuate way, patients walk unsteadily, the floor seems uneven to them, the steps of the stairs seem to be higher or lower. All this affects the psyche of patients, causes dizziness, headaches, nausea, and sometimes vomiting.
With longer use of glasses, all these phenomena disappear; previously acquired ideas about the size, shape and distances of objects help to see everything around the same way with and without glasses. But some patients with high myopia still cannot cope with all these phenomena and get used to glasses. This has to be taken into account and sometimes weaker lenses are prescribed. Some patients have to give special advice to get used to the prescribed glasses as soon as possible. For example, it is recommended to first wear glasses only in your room; when the patient is accustomed to wearing spectacles in the room, allow him to learn to walk up and down stairs, first in the house in which he lives; further allowed to go out and walk only along their familiar street, and then in unfamiliar places. If the patient stubbornly wears glasses, taking them off only when he is tired, and after resting, putting them on again, then, of course, he will eventually get used to it.
When correcting a myopic eye, it is not always possible to obtain full visual acuity; sometimes, despite the most careful correction, even good visual acuity is not achieved; often corrected visual acuity ranges from 0.3 to 0.1, and sometimes even lower. In these cases, it is still possible to give lenses that completely correct myopia for distance, but for near, it is impossible to prescribe a complete correction even for young people. Such a patient, in order to better examine small objects, will involuntarily bring them closer to the eyes, trying to achieve a larger image size on the retina. These patients have to prescribe significantly weaker lenses for near than for distance, by 3.0; 4.0 or 5.0 D is weaker, depending on the degree of myopia and guided by the subjective indications of the patient.
Myopia is quite often complicated by accommodation spasm. In this case, the degree of myopia increases in accordance with the tension of accommodation, and there is always a fear, with a subjective study, to determine a higher degree of myopia. Therefore, especially during the first selection of glasses for the correction of myopia in childhood and young age, atropine should be widely used, prescribing it at the slightest suspicion of accommodation spasm.
Spasm of accommodation in such cases is caused by increased convergence: strongly convergent, the myopic eye and strongly accommodates,
Spasm can complicate myopia of all degrees - from low to the highest. Spasm of accommodation is mostly observed in nervous, impressionable, young people who, by the nature of their profession, have to work close to small objects for a long time and without intervals. These people do not tolerate prolonged stress of accommodation very well. Their eyes turn red, watery, become sensitive to light; at the same time, they are not able to continue their work for a long time and are forced to interrupt it often. Such symptoms of irritation appear periodically and are more common, of course, at a young age, especially with severely progressive myopia. The appointment of atropine in these cases is certainly necessary for a complete rest of accommodation and convergence and for the correct selection of glasses after removal of accommodation spasm.
In addition to spasm of accommodation, myopia is complicated by seizures of muscular asthenopia, in which patients complain of a feeling of pressure and tension in the eyes, while objects merge, become unclear; Complaints about the inability to reduce visual lines to close objects are characteristic. Working close becomes impossible.
The cause of muscular asthenopia lies in the weakness of the internal rectus muscles. Since the attacks of muscular asthenopia are very similar to those of accommodative asthenopia, the presence of muscle insufficiency has to be established by the Graefe method or the Maddox method (small scale for the study of heterophoria).
Before proceeding to the presentation of the tasks for the correction of myopia, it remains to say a few words about the prevention of the progression of myopia and the prevention of complications of myopia.
1. The work time of a patient with high myopia should be limited: reading, writing, drawing, etc. should not exceed 4 hours a day, with breaks for rest. Therefore, it is of great importance for such a patient to choose a profession with the least load for visual strain at close range.
2. Working conditions for a patient with high myopia should be the most favorable. If the act of seeing occurs under unfavorable conditions (poor lighting, very small work, poor correction of myopia, etc.), then this can cause the development of serious complications.
3. Heavy physical work, heavy physical exercises (gymnastics on shells, various sports, such as playing football, running, jumping, wrestling, etc.) can cause complications of myopia, which should be warned the patient *.
4. Disorders of adaptation observed in high myopia, due to dysfunction of the pigment epithelium, force us to recommend to such persons caution when moving, working in daylight.
5. Patients should avoid conditions that cause a rush of blood to the head, such as washing in a hot bath, washing the head with hot water, drinking alcohol, exercising in a hot room, wearing tight collars, sharp tilting of the head during exercise, constipation.
The five points outlined are a kind of commandment for people with progressive myopia.
Until recently, the measures taken to prevent the progression of myopia in students were mainly reduced to the correction with spherical glasses, to the creation of the correct hygienic conditions during intense visual work, which indirectly reduced the need for accommodation and convergence stress, vitaminization and tissue therapy.
In 1957, the physician E. V. Utekhin and the opto-mechanical engineer Yu. A. Utekhin proposed to use for this purpose, in addition to existing measures, special bifocal spheroprismatic glasses, which significantly reduce the necessary accommodation and convergence when working close. The glasses are designed in such a way that they allow the use of spherical prismatic elements near, and for distance vision - ordinary glass for the correction of myopia. A new method for preventing the progression of myopia seems to be theoretically justified. However, it needs further clinical validation.
Task 11. A 15-year-old student complains of poor distance vision. I noticed visual impairment about 5 years ago. She didn't wear glasses.
In both eyes visual acuity 0.06, with myopia correction in 3.5 D visual acuity 1.0; skiascopically: in both eyes myopia is 3.0 D. The nearest point of clear vision with glass is 3.0 D - at a distance of 12 cm.
In cases where there are no special indications for prolonged atropinization, one can successfully use its substitute - a 4% solution of homatropin, which is instilled into the patient's eyes once in the doctor's office. An hour after instillation, the patient is examined; by that time, the pupils dilate and complete paralysis of accommodation occurs, which disappears after 24 hours.
Both eyes were instilled with 4% homatropin once and asked to sit in the waiting room for one hour. An hour later, the patient was examined with maximally dilated pupils. Visual acuity 0.03; with myopia correction in 3.0 D visual acuity 1.0; skiascopically: myopia 3.0 D in both eyes.
Diagnosis. Myopia at 3.0 D in both eyes.
We assign glasses - a complete correction for constant wear.
We write out the recipe:
Glasses for permanent wear:
right eye -3.0 D
left eye -3.0 D
Dp. = 52 mm
Task 12. A 7-year-old girl sees very poorly far and near, reads, leaning very close to a book. She didn't wear glasses. Visual acuity of each eye 0.01, with myopia correction 8.0 D, visual acuity 0.3; left eye: visual acuity 0.01, with myopia correction 7.0 D, visual acuity 0.4.
On the fundus, there is a cone on the temporal side of the optic nerve papilla, half the diameter of the nipple, with patches of pigment along the edge of the cone.
Atropinization is prescribed for 5 days.
In the study under atropine with maximally dilated pupils: visual acuity of the right eye 0.01, with correction of myopia 6.0 D, visual acuity 0.3; visual acuity of the left eye 0.02, with correction of myopia 5.0 D visual acuity 0.4.
After additional atropinization for 5 days, the same data were obtained. Skiascopy: on the right eye M 6.0 D, on the left eye M 5.0 D.
A complete correction of myopia (glasses for permanent wear) is prescribed. Astigmatism of 0.5 D is not corrected, since cylindrical glasses do not improve visual acuity. It is recommended to read and write, keeping the work as far away from the eye as possible, study in good lighting, take breaks in classes every 40-45 minutes. A note is given to the school so that the girl is put on the first desk and released from physical education lessons.
A prescription is issued:
Glasses for permanent wear:
right eye - 6.0 D
left eye -5.0 D
Dp. = 52 mm
Task 13. The patient, 16 years old, sees far and near very badly. Never wore glasses.
Visual acuity of both eyes 0.04; M 15.0 D, visual acuity with a correction of 0.4.
Some ophthalmologists say that vision problems are the price we have to pay for being civilized and educated… But these words are so far from the truth! Vision problems are solved quite simply without expensive operations and glasses / lenses. I can help you solve this problem!
Skiascopically:
Nearby, he reads fine print No. 5 of the Golovin-Sivtsev table at a distance of 6 cm from the eyes, while one eye deviates sharply outward; when set far away, strabismus is imperceptible. There are large circular cones in the fundus, depigmentation and mottling in the macular area.
Diagnosis. High myopia, degenerative changes in the macular region and insufficiency of the internal rectus muscles.
The patient categorically refused atropinization.
It is impossible to prescribe a complete correction, since it will be very difficult for the patient to get used to strong glasses. On the other hand, due to the presence of divergent strabismus, it is necessary to give glasses that are close to complete correction. The latter is necessary in order to increase visual acuity, to enable reading, writing and working at a close to normal distance (about 20-25 cm) and thereby facilitate convergence; the presence of strabismus indicates that the internal rectus muscles no longer cope with work at close range due to their insufficiency. We stop at -12.0 D lenses, which achieve visual acuity of 0.3 and it is possible to freely read font No. 6 at a distance of 25 cm. Font No. 5 reads with difficulty at a distance of 18 cm. The patient feels good in these glasses. We indicate that it is necessary to get used to the glasses gradually.
We write out the recipe:
Glasses for permanent wear:
right eye -12.0 D
left eye -12.0 D
Dp. = 64 mm
Task 14. A 13-year-old girl complains that she sees very poorly far and near; cannot study, especially in the evenings, the letters merge; the eyes are watery, redden, the head starts to hurt. After a rest, he can practice again, but soon the letters begin to merge again. The mother adds that her daughter is leaning very close over the book. Never wore glasses.
The girl has mild photophobia, the edges of the eyelids are thickened, covered with crusts, scales, there are few eyelashes, the conjunctiva of the eyelids and transitional folds are hyperemic. Visual acuity in both eyes 0.14; M 4.5 D with correction visual acuity 1.0; reads small print at a distance of 7 cm equally with both eyes; when the font is moved away from the eye by 8-9 cm, the girl cannot read anything. There is a spasm of accommodation; skiascopically: hypermetropia of 0.5 D after the girl sat in a dark room for 1 hour.
When re-examination of visual acuity according to the tables, myopia of 4.5 D was again detected, visual acuity with correction is 1.0.
Diagnosis. Spasm of accommodation, false myopia, chronic blepharoconjunctivitis, accommodative asthenopia.
Atropinization is prescribed for 2 weeks, school visits and all classes are prohibited. Atropine is prescribed not only to detect all hypermetropia, but also to treat spasm. .
A week later, the pupils are dilated as much as possible: visual acuity of both eyes 0.2; with -0.5 D visual acuity 0.7; skiascopically: H 0.5 D in both eyes.
After 12 days: visual acuity of both eyes 0.2; H 1.0 D, visual acuity with correction 0.7; skiascopically: H 1.0 D.
After 14 days: visual acuity 0.3; H 1.0 D, visual acuity with correction 0.8; skiascopically: H 1.0 D.
Glasses are prescribed for permanent wear + 1.0 D for both eyes, i.e., complete correction of hypermetropia. It is recommended to start wearing glasses immediately after atropinization, with wide pupils.
A prescription is issued:
Glasses for permanent wear:
right eye +1.0 D
left eye + 1.0 D
Dp. = 54 mm
General treatment, vitamins, fish oil are prescribed. Sent to a neurologist.
A week later, the patient with glasses sees well, but still cannot read. We suggest gradually starting to read and write at a distance of 25-30 cm. Visual acuity with correction H 1.0 D = 1.0.
A week later, the patient already sees well both far and near, reads at a distance of 25 cm without fatigue: headaches have stopped: the phenomena of blepharoconjunctivitis have almost disappeared.
This case is very interesting, since such a large spasm of accommodation is rare, and cases of false myopia of such a large degree are not frequent.
Task 15. Turner, 25 years old, can't see well into the distance. It is also inconvenient to work, you have to lean very close to the machine. Never wore glasses.
Visual acuity of the right eye 0.08; M 4.5 D, visual acuity with a correction of 1.0; visual acuity of the left eye 0.06; M 5.5 D, visual acuity with a correction of 1.0; skiascopically: in the right eye myopia was 4.0 D, in the left eye 5.0 D.
The closest point of clear vision with myopia correction is at a distance of 13 cm, i.e., corresponds to the age of the patient. The volume of accommodation is calculated by the formula:
A \u003d R-R \u003d 100 / -13-0 \u003d -7.5 D.
Temporal cones on the fundus.
Diagnosis. Moderate myopia.
Spectacles that completely correct myopia are prescribed for permanent wear. From the formula for calculating the volume of accommodation, it can be seen that the patient owns his accommodation, like an emmetrope.
A prescription is issued:
Glasses for permanent wear:
right eye -4.0 D
left eye -5.0 D
Dp. = 62 mm
Task 16. A student of a construction technical school, 16 years old, wears glasses - 4.0 D, which he was assigned 2 years ago. He sees well in them, but he gets tired and cannot wear them for a long time: it is very difficult to read and draw in them.
Visual acuity of the right eye 0.1; M 3.0 D, visual acuity with correction 1.2; visual acuity of the left eye 0.17; M 2.5 D; visual acuity with correction 1.2. With glasses (- 4.0 D), visual acuity is also 1.2.
The nearest point of clear vision with corrective lenses is at a distance of 8 cm for both eyes. With glasses (- 4.0 D), the nearest point of clear vision is 14 cm, i.e., like a 28-year-old; skiascopically: on the right eye myopia - 2.5 D, on the left - 2.0 D. With glasses -4.0 D. The patient has hypercorrection. The glasses are too strong because myopia is overcorrected.
Atropinization is prescribed for 5 days. After 5 days, with the most dilated pupils, skiascopically on the right eye, myopia was 2.5 D, on the left 2.0 D. Visual acuity with a correction of 1.2.
A prescription is issued:
Glasses for permanent wear:
right eye -2.5 D
left eye - 2.0 D
Dp. = 60 mm
Task 17. The director of the printing house, 49, complains of very poor eyesight. He wears glasses -18.0 D, in them he sees poorly both far and near. Myopic since childhood: I started wearing glasses from the age of 10, gradually strengthening them. She has been wearing her last glasses for 7 years.
Visual acuity of the right eye 0.01; s -28.0 D; visual acuity 0.12; visual acuity of the left eye 0.02; s - 26.0 D; visual acuity 0.14; skiascopically: right eye M 30.0 D, left eye M 28.0 D. In the fundus there are extensive circular cones, multiple atrophic chorioretinal foci in the macular region and in the circumference of the nipples of the optic nerves.
Diagnosis. High myopia, central myopic chorioretinitis in both eyes.
We try stronger glasses for a distance: the right eye with - 24.0 D gives visual acuity of 0.1; the left eye with - 22.0 D gives a visual acuity of 0.12. According to the patient, he sees much better with these glasses; in their points of the top line of the table Golovin - Sivtseva does not make out.
For near, we assign weaker lenses.
Taking into account the age and subjective indications of the patient, we write out the following prescriptions:
Near glasses:
right eye - 20.0 D
left eye - 18.0 D
Dp. = 64 mm
Distance glasses:
right eye - 24.0 D
left eye -22.0 D
Dp. = 66 mm
Task 18. The artist, 59 years old, has glasses for distance - 3.5 D, which he has been wearing for a very long time. Reads well without glasses, but he needs glasses to work in his specialty; you need to see the model, and then transfer your gaze to the canvas, i.e. distance 40 -
50 cm. Asks to pick up such glasses in which you can work without taking them off.
Visual acuity of both eyes 0.05; M 4.5 D, visual acuity with a correction of 1.0; skiascopically: myopia in - 4.0 D.
Diagnosis. Myopia.
For the work of the artist, it is advisable to assign bifocal glasses. -4.0 D can be given to the top of the glass; in the lower one, to work at a distance of 40 - 50 cm, glasses are needed weaker. 50 cm corresponds to the distance of the further point of clear vision of the eye with myopia in 2.0 D, therefore, our patient needs a lens - 2.0 D.
We write out the recipe:
The patient does not need reading glasses.
Task 19. A 26-year-old accountant complains of poor distance and near vision. Glasses, never worn. Visual acuity of the right eye 0.03, with correction of myopia 14.0 D visual acuity 0.5; visual acuity of the left eye 0.04, with correction of myopia 12.0 D, visual acuity 0.6; skiascopically: in the right eye myopia 13.0 D, in the left eye 11.0 D.
Fundus of the eye: extensive circular posterior staphylomas and depigmentation in the area of yellow spots.
The closest point of clear vision in the study with lens correction - 13.0 D on the right eye at a distance of 20 cm; without glasses reads font No. 5 of the Golovin-Sivtsev tables at a distance of 10 cm.
Since the patient has never been examined during atropinization and complains of fatigue when working at close range, atropinization is prescribed.
Diagnosis. High myopia, spasm of accommodation.
Re-examination after 3 days, with maximally dilated pupils: visual acuity of the right eye 0.02, with myopia correction 10.0 D visual acuity 0.5, with aperture 0.7; in the left eye visual acuity 0.02, with correction of myopia 9.0 D; visual acuity 0.5 with aperture 0.7; skiascopically: myopia 10.0 D in the right eye, myopia 9.0 D in the left.
Atropine is prescribed for another 2 days. In the third study, the same data were obtained skiascopically and subjectively as in the previous study.
We write out the recipe:
Glasses for permanent wear:
right eye -10.0 D
left eye - 9.0 D
Dp. = 64 mm
The patient is warned that it is necessary to get used to the glasses gradually, at first it will be inconvenient to walk in them, all objects will seem reduced, it will also be difficult to read and write with glasses; if your eyes get tired, you need to take off your glasses and rest, and then put them back on. The book should be kept at a distance of about 25 cm. Lying down is also impossible to read. Start wearing glasses with dilated pupils.
After 3 days the patient was examined: the glasses were made correctly. The patient says that it is really difficult for him to walk down the street, he stumbles, the floor seems uneven.
When re-examination a month later, it was found that the patient was accustomed to glasses. There are no side effects.
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