Laser eye surgery for astigmatism: correcting astigmatism with EyeLaser

A tried and tested procedure without touching and without a flap. Transepithelial photorefractive keratectomy (Trans-PRK for short) does not require a corneal incision and is therefore particularly gentle on the tissue.

Without a corneal incision and is therefore particularly gentle on the tissue.

An excimer laser ablates the surface of the cornea and shapes the corneal tissue in such a way that the light is focused precisely on the focal point and the visual defect(s) are corrected.

Advantages of astigmatism correction with Trans-PRK:

• Can be performed without corneal incision and contact
• High corneal stability is maintained
• Treatment of superficial corneal opacities
• Tissue-friendly procedure
• Also possible for thin corneas & dry eyes

Requirements for a Trans-PRK:

• Short-sightedness: -8 diopters
• Farsightedness: +3 diopters
• Corneal curvature: 6 diopters

Since 1991, more than 50 million people have had their visual defects corrected with LASIK. Laser in situ keratomileusis means “changing the shape inside the cornea”. The cornea is cut with a high-precision femtosecond laser so that the top layer can be folded back (flap).

The corneal curvature and all other visual defects can then be corrected using the excimer laser. The flap is then “folded back” and heals completely.

Advantages of Femto-LASIK 7D:

• Extremely precise corneal flap
• Gentle removal of the cornea
• Precise and individual modeling of the cornea
• Rapid visual recovery after the procedure
• Uninterrupted blood flow to the retina
• See clearly the very next day

Requirements for Femto-LASIK 7D:

• Short-sightedness: up to -10 diopters
• Farsightedness: up to +4 diopters
• Astigmatism: up to 6 diopters
• Corneal thickness: at least 480 micrometers

The innovative procedure with the SCHWIND ATOS laser requires only a single, tiny incision (2-3 mm). The femtosecond laser forms a lenticule on the cornea, which is then removed through the incision. The lenticule is shaped in such a way that the cornea is modeled in such a way that it then correctly refracts incoming light rays.

The most popular variants of lenticel extraction are: ReLEx SMILE (Pro), Clear and SmartSight. At EyeLaser Vienna, Linz and Zurich, we rely on SmartSight.

Advantages of SmartSight:

• Can also be used for more pronounced astigmatism
• Gentle on tissue due to lenticular geometry
• Extremely fast healing and high safety
• State-of-the-art laser technology (eye tracking, cyclotorsion compensation, etc.)
• No flap, no cut & no surface abrasion
• Can be individually adapted to the patient’s visual defect

Requirements for lenticel extraction:

• Short-sightedness: up to -10 diopters
• Astigmatism: up to – 6 diopters

If farsightedness is present and needs to be corrected, SmartSight is not yet an option. This is because it cannot be corrected in the course of lenticule extraction. In this case, it is better to use one of the four other procedures.

In addition to the possibility of having astigmatism corrected by laser, there is lens surgery, which takes a fundamentally different approach to correction. No laser is used (apart from the Femto lens exchange).

The problem is solved by adding a toric artificial lens or replacing the natural lens with toric artificial lenses.

Lens implantation – ICL Phake lenses

If laser eye surgery is not possible or the astigmatism is too pronounced, ICL lens implantation is an option, especially for younger patients. The natural lens remains in the eye and is supplemented by an artificial lens that is inserted in front of or behind the natural lens.

The toric ICL Phake lens (EVO/EVO+ VISIAN ICL), which is specially made for astigmatism, optimally compensates for refraction and, together with the crystalline lens, ensures that the visual defect(s) are corrected.

Advantages of lens implantation:

• Thinner and deformed corneas (including keratoconus) are not a problem
• Correction of very severe visual defects possible
• Replaceable in case of changes in visual acuity
• Integrated UV protection for the eyes
• Also suitable for dry eyes and / or contact lens intolerance
• Individually adapted to the patient’s exact visual defects

Requirements for an ICL Phake lens:

• Short-sightedness: up to -23 diopters
• Farsightedness: up to +10 diopters
• Astigmatism: up to 10 diopters

The natural lens is completely removed and replaced by a toric artificial lens. This procedure is particularly suitable for older people (aged 55 and over), as presbyopia can be corrected and cataracts can be cured or prevented.

Patients can choose between two types of artificial lenses – both available as toric and non-toric versions – for people without astigmatism.

1. Toric monofocal lenses: Only one focal point, so that after the procedure you can only see sharply at near or far distances.
2. Toric multifocal lenses / EDOF: Multiple focal points for sharp vision over all distances without glasses. EDOF = with extended depth of field for a smooth transition and even more natural vision.

If the indication for lens replacement is not vision correction, it is referred to as cataract surgery. The procedure, costs and result do not differ.

Advantages of lens replacement:

• Precise correction of astigmatism possible without laser
• In addition to “normal visual defects”, presbyopia & cataracts can also be treated
• Complete and permanent healing of cataracts
• Development of corneal opacity is prevented forever
• With multifocal lenses, glasses and contact lenses can be dispensed with

Requirements for lens replacement or cataract surgery:

• Short-sightedness: from -6 diopters
• Farsightedness: from +4 diopters
• Astigmatism: up to 6 diopters

If you have a diseased or scarred cornea or retinal disease, it may not be possible to replace the lens.

Before the optimum treatment for you can be selected, a comprehensive preliminary examination is carried out. The results lay the foundation for your independence from visual aids. Among other things, we carry out the following examinations to determine the type and severity of the astigmatism:

• Objective refraction:

Measurement of the sharpness of a projected image using different lenses.

• Subjective refraction:

Selection of a lens with which the patient has the impression of seeing the eye chart clearly.

• Corneal topography:

Especially for irregular astigmatism to determine the exact condition of the cornea.

• Ophthalmometry:

Determination of the refractive power and the values for the radius of curvature of the cornea by projection or measurement of their deviations.

• Check whether other eye diseases or scarring speak against surgery

Afterwards, it can be said with certainty whether a correction of the astigmatism is possible and which procedure is suitable. Whether you decide to undergo surgery is up to you – the preliminary examination is non-binding and costs 200 euros.

Arrange a preliminary examination

If only the suitability is to be checked – without a thorough examination – this will not cost you a cent.

Arrange an aptitude test

Based on the results of the preliminary examination, we will select the method that best suits your eyes, your lifestyle and your budget.

Astigmatism can be corrected by Trans-PRK 7D, Femto-LASIK 7D, SmartSight or artificial lenses (ICL Phake lenses or lens exchange).

The procedure varies depending on the procedure. However, they all have one thing in common:

• Can be performed on an outpatient basis in less than two hours
• Painless thanks to anesthetic eye drops
• Fast (on average 15 minutes with a few seconds of laser use)
• Safe thanks to state-of-the-art equipment and experienced surgeons
• Effective with a high patient satisfaction rate

The healing period depends on the chosen method – between a few days and several weeks. The fastest healing is expected after SmartSight (only 3 days). The time after the treatment is usually pain-free and has few complications. Itchy, burning, and watery eyes or a slight foreign body sensation are completely normal after-effects, which are generally harmless and disappear on their own.

The astigmatism healing process is supported by eye drops – applied according to an individual drip schedule – antibiotics and, if necessary, painkillers.

Even if you can see better immediately after the minimally invasive procedure, it takes some time (depending on the method, days to a maximum of 4 weeks) until your brain has adapted and you can enjoy maximum, permanent visual acuity.