08.11.2023
|
4 min. reading Night lenses: are they an alternative to children's glasses?
Night lenses appeared more than 20 years ago in America, but they became available in Ukraine much later. How do they differ from soft daytime ones, what are their advantages for children, and is this a marketing ploy? Every day I hear similar questions from parents of young patients. Therefore, let's talk about an alternative to the lenses or glasses we are used to.
Source: freepik
Yaroslav Koshelenko
What is this phenomenon?
Night lenses are also called orthokeratological or rigid. They are a modern method of vision correction for refractive errors. These are the same contact lenses as daytime ones, only the silicone from which they are made is otherwise cleaned. The gas-permeable material completely allows oxygen from the tear to the cornea, which is very important for the eyes. Unlike the lenses we are used to, they are worn not during the day, but at night. And this is their advantage.
In diameter, the night lens is slightly smaller than the day lens and is precisely calculated for the cornea. Therefore, the diameter is selected for the patient. As well as the necessary curvature of its surface.
When a child puts on a lens before going to sleep, it presses on the cornea, "sucks" to it like a piston. This allows you to passively influence the corneal epithelium. As a result, the epithelium in the central region of the eye is redistributed to the periphery, and by removing the lenses in the morning, the child sees well during the day. This is the principle of correction.
The topography of the cornea (three-dimensional model), which we do after the small patient has removed the lens, resembles laser correction. I will give an analogy. Imagine that you put on a smaller sock and walked in it all day. In the evening, when you take it off, there will be a trace of the rubber band on your leg. The same mark remains on the cornea of the eye after wearing a night lens. And it resembles laser correction.
Mechanism of action
Imagine a dome - it has its own curvature inside. If the surgeon grinds a certain part of the cornea with a laser, the lens presses the same part. Reconstruction of the surface epithelium of the cornea occurs due to the complex relief of the inner surface of the lens.
Source: freepik
What to choose — day or night lenses?
First of all, consider three main factors. Night lenses are definitely not suitable:
- If the child sleeps less than 8 hours, then this type of correction will not work properly. To achieve the effect, it takes 8-9 hours, but no more than 10;
- if the degree of refraction goes beyond the action of the lenses;
- in the case of pure astigmatism or farsightedness.
Consequently, ortholenses are prescribed to those who suffer from myopia or myopia together with astigmatism. The degree of myopia subject to such correction should be from -0,5 to -6, astigmatism - to -4.
Important: the level of astigmatism must be less than myopia.
How long does the correction effect last after sleep
It all depends on the degree of refraction anomaly. If myopia is from -0,75 to -2, the effect can be expected already after the first night. But after twelve or two hours of the day, the child can see a little worse. However, the next day the effect will be stronger and last longer. Here the essence is in cumulative action.
The higher the degree of myopia (minus), the later the lenses work: approximately on the fifth or sixth day, you can get 100 percent vision. For example, the child woke up early, took off the lenses - and sees very well, but this will continue until four in the evening. It is individual for everyone.
Main remarks:
- night lenses are designed for annual wear;
- must be worn every night;
- in case of illness: runny nose, cough, temperature - lenses are not worn. This, by the way, applies to all species. In case of a cold or SARS, you should have glasses.
Source: freepik
Are there any contraindications?
In addition to the infectious diseases mentioned above, there are such contraindications:
- degeneration of the cornea;
- diabetes;
- violation of connective tissue;
- all inflammatory and allergic conditions.
Is there anyone who is recommended to wear night lenses?
Of course, for children. It is very convenient for parents, because:
- lenses are always at home, so they will not be lost or fall out of the eye;
- Children are free from glasses and daytime lenses all day. This eliminates the danger that a six-year-old girl or a schoolboy might run, bump into something and break her glasses, or get something under the lens.
- Night lenses are perfect for children, because they prevent the progression of myopia. They press on the cornea (we remember that this causes a redistribution of cells on the periphery) and inhibit the growth of the eye. This stabilizes myopia.
What are the types of night lenses?
The principle of operation of such lenses is the same, only the manufacturers differ. In the clinic, we work with Paragon or Moonlens products. Personally, I prefer the second company, because its products, given the current wartime, are delivered faster. Plus, a larger number of lens diameters are offered, and it is also possible to change the material.
It should be noted that the service life of the lens depends on the material. If it is softer, then the period of use is shorter.
Features of lens selection
First of all, you need to check your eyesight. If it is below 78-80%, night lenses are not used. Likewise, if a person has amblyopia.
Next, a topographic map of the cornea is made, it can be compared with a topographic map of the area, only in our case - the cornea of the eye.
The next stage is lens selection. We calculate it, put it on the eye, see how it sits. If the patient is satisfied with everything, we issue it. Now, due to new realities, we are ordering a lens.
Source: freepik
Features of lens storage
The night lens must be cleaned. There are three options:
- ultrasonic cleaning. Special devices are sold on the Internet. The cleaning process lasts 5 minutes;
- special shampoo. Pour the ego into your hand and wash the lens for 30 seconds, and then rinse with the usual solution;
- peroxide system. The lenses are placed in a special container with a peroxide solution for 8 hours. Then they are washed with a normal solution.
Personally, I recommend the first two cleaning methods.
What do we do when the hour of using the lenses has passed
After an hour, when the child removes the lens, a break is made for two weeks. Then he will need glasses or contact lenses. The effect of night lenses will gradually disappear, but for the first two or three days he will be able to walk without glasses.
Next, the child is brought for re-diagnosis to determine what his minus is. And we select and try on new night lenses. Everything, your child is provided with good eyesight again for an hour!
The opinion of the editors may not coincide with the opinion of the author of the article.
Use of photo: P.4, Article 21 of the ZU "On copyright and related rights - "Reproduction for the purpose of covering current events by means of photography or cinematography, public communication or communication of works seen or heard during such events, to the extent justified by the informational purpose."
Be the first to leave a review