Lenses that completely overlap the protein membrane of the eye – the sclera, are called scleral. They are mainly used for cosmetic purposes. sclera lenses With their help, you can create a truly demonic, frightening image. Wearing such contact optics is not recommended daily and for a long time.
Lenses for the whole eye are lenses with an increased diameter. If in conventional models this parameter is approximately 14 mm, scleral ophthalmic products have a diameter of up to 24 mm. Their shape is somewhat convex. Due to this, between the lens and the cornea there is a small space in which tear fluid accumulates. It moisturizes the surface of the cornea.
Sclera lenses are made from hydrogel materials. They are well moistened, but have a not very high rate of oxygen permeability. This affects the wearing mode of this contact optics. However, the consequences of improper operation will be considered later. First, find out when it is appointed.
Prescribing sclera contact lenses
Lenses for the whole eye are worn not only in order to create an unusual visual effect. There are many medical indications for their use. So, sclera lensesare used in oculography. This method of examining eyeballs allows you to track their movements in dynamics, that is, in the process of healing and restoration of the eyes.
The advantage of lenses for the whole eye is that they do not need to be removed before inspection. They do not close the review. The doctor can see all the eye structures. In the treatment of various ophthalmic diseases, this examination method reduces the risk of infection in the eyes.
Sclera contact lenses also act as bandages for the protection and rapid restoration of the cornea after transplantation or laser surgery to correct vision. Color models do not have any therapeutic effect, do not protect the eyes from germs and are not equipped with optical power. They are needed only to change the image.
Lenses without pupils: advantages
Lenses without pupils, lenses for the whole eye, scleral ophthalmic products are different names for one type of color contact optics. They are made from modern materials based on hydrogel, due to which such lenses are very convenient. In addition, they are resistant to mechanical damage. Their structure is very dense. The coloring pigment in the production process always lies in the thickness of the ophthalmic product. The dye is not washed with a tear and does not interact with the tissues of the eye. There is a myth that colored lenses cause allergies and irritation due to the paint entering the cornea. However, this is not possible. The main thing is to purchase contact optics in specialized stores.
How to wear sclera lenses?
Of course, these ophthalmic products are not used to correct refractive defects, but there are other parameters besides optical power, which are important to determine when selecting contact optics. These parameters include radius of curvature and diameter. The size of the human eye is normally 23-24 mm. Sclera lenses are available in diameters from 14 to 24 mm. If this indicator does not match the eyeballs, ophthalmic products will shift or, on the contrary, squeeze the eyes.
Actually, the process of installing sclera lenses is no different from the procedure for putting on conventional means of contact correction. Wash your hands before doing so and dry them thoroughly. Put the product on the tip of your index finger, open your eyelids with your free right hand and mount the lens on the eye, pressing it against the sclera.