Laser therapy for astigmatism

introduction

Astigmatism, colloquially known as corneal curvature or astigmatism, is a widespread ametropia in addition to classic farsightedness and myopia. Until a few years ago, her treatment was mostly carried out using special glasses or contact lenses.

For several years now, ophthalmologists have been offered another treatment option: lasers. This low-complication and gentle treatment method is now very widespread and is offered a thousand times a year in numerous eye clinics and specialized laser eye centers. However, their use is limited to a certain extent and usually associated with high costs. The following article will give you an overview of astigmatism and its laser treatment.

General information on the subject can be found at Astigmatism, Laser eye

Astigmatism

A sharp picture can only be achieved on the Retina arise when all light rays can be bundled in one point on the retina. If this is not the case, image disturbances will occur, i.e. distorted or blurred images. These can arise, for example, from a disproportion between the refractive power of the lens and the length of the eyeball.
At myopia for example, the eyeball is relatively too long, the rays of light are already bundled in front of the retina. In the Farsightedness on the other hand, the eyeball is relatively too short so that the light is focused behind the retina.
In contrast to these two widespread ametropia, the cause of astigmatism is in most cases one uneven shape of the cornea, from which its colloquial term as corneal curvature results. The light is refracted differently depending on where it hits the cornea and hits the retina in a distorted manner. A distinction is made between different forms of astigmatism.

The most common is the regular astigmatism in which the incident light rays are not imaged in a focal point but in focal lines that are perpendicular to one another in the shape of a rod (hence the term "Astuteness"). Astigmatism can also irregular be trained. Therefore, those affected perceive their surroundings in different degrees of blurring.

Is astigmatism mostly innate, but it can also have other causes, such as a Scarring of the cornea in the context of inflammatory and traumatic events or after surgery. The consequences of astigmatism are usually only noticeable when they are more pronounced. Besides the obviously occurring blurred vision Affected can also under Eye pain and headache Suffer. If children are affected by a pronounced astigmatism, they can also develop permanent visual impairment.

In addition to an incorrectly curved cornea, a deformed lens or a disorder in the functioning of the eye muscles be the cause of a distorted refraction of light and thus an astigmatism. The term astigmatism itself is therefore relatively broad overall. However, the following article will only deal with astigmatism or astigmatism.

Astigmatism in children

Astigmatism, which only develops in adulthood, is harmless for those affected, even if it is uncomfortable. This is not the case with children. Refractive errors of any kind can theoretically occur with you lead to permanent visual impairment in the affected eye, because the visual pathway of this eye cannot develop in a healthy way and vision is taken over by the healthy eye. To put it simply, the brain hides the weaker eye as part of its development in childhood.The visual pathway, which is accordingly not fully developed, includes not only the retina and the optic nerve, but also the associated conduction pathways and corresponding areas of the brain.
However, in the first two years of life uninterrupted remodeling processes of the nerve cells in the brain instead, so that missing nerve tracts can still be developed. Recognizing astigmatism in young children during preventive examinations up to the age of two is therefore extremely important.
Treatment of astuteness in children using lasers does not make sense and is therefore not offered. The background to this is that the eyes, like other parts of the body, are subject to a growth process up to around the age of 18. An intervention therefore only makes sense in adulthood.
Instead it will with children on special glasses with cylinder lenses and a masking of the healthy eye resorted to. Babies and toddlers also need special glasses break-proof plastic. From around the age of five you can then contact lenses provided the child cooperates and the parents take good care of the lenses.

correction

After the strength of the refractive error has been determined with the help of special diagnostics such as the ophthalmometer (for measuring the curvature of the cornea), a correction of the corneal curvature can be sought.
Various treatment methods are available for this. Come in the first place Spectacle lenses with a special cylindrical cut are used, which are therefore also referred to as cylinder glasses. Likewise, according to the individual corneal curvature, so-called toric contact lenses be used. Here you can soft contact lenses, which compensate for the curvature by their shape, from hard contact lenses a distinction can be made, which are usually worn overnight and have the function of shaping the cornea itself. Both cylinder glasses and contact lenses take some getting used to for most patients and can lead to headaches and eye pain in the first few weeks to months. The initial side effects of the treatment are more pronounced the later the astigmatism is treated.
In addition, in some cases operative interventions in the field of refractory surgery (refers to eye surgery) effect a correction of the astigmatism. In extreme cases, the Corneal transplant Another treatment option if other attempts at correction do not produce the desired result.

Lasers for astigmatism

In addition to the treatment methods mentioned above, there is also the possibility of Laser correction, which also belong to the refractory surgery procedures is counted. In recent years, this therapy option has actually developed into one of the most popular correction procedures and is carried out thousands of times a year in many specialized eye centers in Germany.
While various laser processes have since been developed, the LASIK (Laser in situ keratomileusis) is currently the most popular technique. What is remarkable about this method is that no significant damage to the corneal covering tissue takes place, which forms the outer and inner layers of the cornea. Instead, the lens is corrected by evaporating the connective tissue in between Removal of irregularities achieved, whereby the lens is now thinner in places than before the operation. After the operation, the patient quickly gains a sharp and pain-free view.
Whether a laser treatment is an option for the patient is determined individually beforehand by the attending physician using various diagnostic methods and, above all, is depends on the extent of the corneal curvature. Laser correction reaches its limits in the case of astigmatism at around 5 to 6 dioptres. It should also be mentioned that farsightedness cannot be treated with all common laser methods. A combined farsightedness with a rod is therefore difficult to correct with a laser.

Laser therapy costs

In addition to the question of whether a laser treatment brings any benefit, you should find out what costs will be incurred by those affected. These are usually between 800 and 2,500 euros per eye. As a patient, when considering costs, it is important to pay attention to whether the price includes the Costs for pre-care and aftercare are included, as billing is sometimes handled differently from doctor to doctor. If the costs for the patient are too high to be able to pay them in one fell swoop, some providers offer financing over several (usually twelve) months. Eye laser centers in particular offer this service. A (partial) reimbursement of costs by the health insurance takes place only in a few exceptional cases.

Risks of laser therapy

Like classic surgical interventions, the laser treatment of astigmatism is a surgical procedure and is therefore associated with risks. Mild side effects of the procedure may take the form of dry eyes, Foreign body sensation or Glare effects at night but usually go away within a few days to weeks after the procedure. More serious complications, on the other hand, are quite rare and are around 1%, depending on the source. These complications include, for example Keratectasia, one Protrusion of the corneawhich, as a result of its thinning during the operation, can occur with a delay of up to ten years. This affects less than 1 in 100 patients. In order to avoid such complications, it is primarily important to follow your doctor's instructions and attend follow-up appointments. In particular, the prescribed ones apply here Use eye drops regularly as directed. Only in this way can perfect wound healing of the cornea be guaranteed.

From what age does laser therapy make sense?

In order for a laser treatment to be effective and, above all, permanent, it must be ensured that the patient is no longer growing. Otherwise the eye, like other parts of the body, would continue to change as it grows. For this reason, laser eye treatments are generally only carried out from the age of 18.