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Department for Ophthalmology

Ophthalmology

Surgery for defective vision / laser eye surgery

If, for personal reasons, you are not able to cope optimally with glasses or contact lenses, eye surgery (Excimer LASER Operation) can significantly improve your vision.

Eyeglasses and contact lenses temporarily compensate for impaired vision (defective vision). They change the refractive power of the eye by adding a correction value. In contrast, a surgery that changes the refractive power of the eye (refractive surgery) results in a permanent correction of defective vision.

Defective vision

In some respects, the human eye can be compared to a camera. Incoming light is imaged by a refracting lens system (the lens in the camera; the cornea and the lens in the eye) in such a way that a sharp image is produced on the light-sensitive layer (the film in the camera; the retina in the eye).

A sharp image can only be produced both in the camera and in the eye if the respective lens system correctly refracts the light rays from the outside world and thus produces a sharp image on the film or on the retina. Otherwise, this is referred to as defective vision and those affected have blurred vision.

  • Near-sightedness (myopia)

    With near-sightedness (myopia), the eye is too long in relation to the refractive power of the optical system. The excessive refractive power produces a sharp image in front of the retina. Those affected have blurred vision in the distance.

  • Long-sightedness (hyperopia)

    With long-sightedness (hyperopia), the eye is too short in relation to the refractive power of the optical system. Due to the insufficient refractive power, a sharp image is only produced ‘behind the eye’. At long distances, those affected usually have sharp vision, but blurred vision at close range.

  • Curvature of the cornea (astigmatism)

    Most patients with near-sightedness or long-sightedness also have a certain degree of astigmatism in their cornea. Astigmatism means that the cornea is not round in its curvature (like a ball), but somewhat oval (in extreme cases like a rugby ball).

    Starting with an astigmatism of around 0.5 dioptres, objects may be distorted or shifted. Dots are seen like a rod (hence astigmatism). Higher astigmatisms are often difficult to correct with eyeglasses.

  • Presbyopia

    Presbyopia is part of the normal ageing process, whereby the eye's natural lens loses its flexibility. When adjusting the eye to near objects (‘short distance accommodation’), the lens of the presbyopic person can no longer bend sufficiently. It is no longer possible to see clearly at close range. Presbyopia occurs in everyone between the ages of 40 and 50.

    To date, presbyopia cannot be treated satisfactorily by surgery. A large number of surgical techniques are still at the experimental stage.

  • Higher order optical errors

    Higher-order refractive errors are irregularities that can arise, for example, due to a shift in the optical centres of lens systems connected in series (coma) or different refractive forces in the centre and in the outer areas of lenses (spherical aberration). However, different refractive powers of the lenses for light rays with different wavelengths (chromatic aberration) can also be a trigger.

    All these refractive errors exist in the human eye. However, they are usually so small that they do not cause any major problems with vision. Due to their physical properties, they cannot be corrected with glasses or soft contact lenses.

    The latest generation of diagnostic devices includes high-precision topography devices and so-called wavefront aberrometers, which can determine higher-order refractive errors individually for each eye with a high degree of accuracy. With the help of the latest generation of Excimer lasers, it is now possible for the first time to correct these higher-order refractive errors in a targeted manner.

Surgical methods / laser eye surgery

Are you interested in a surgical correction of your vision?

We would be happy to advise you on the subject of eye surgery for defective vision. We present the individual surgical methods and discuss the requirements and possible risks. Our doctors will be happy to answer your personal questions.

Refractive Surgery Office

0941 944-9285 or 0941 944-9242

 

  • Requirements
    • The visual defect must be stable, i.e. no change of more than 0.5 dioptres in the last two years.
    • The patient should be at least 18 years old.
    • The patient should not have any other eye diseases (e.g. glaucoma).
    • The patient should not suffer from general illnesses (e.g. rheumatism, diabetes mellitus, wound healing disorders).
    • The patient should not be taking any medication that could affect the healing of the cornea.
    • Treatment during pregnancy and breastfeeding should be avoided.
    • For patients suffering from allergies, the surgery should be scheduled during the allergy-free period.
    • In order to be able to examine the eyes, it is necessary to remove soft contact lenses at least four days before the examination and hard contact lenses at least four weeks before the examination and to wear eyeglasses during this time. 

  • Surgical techniques
    • LASEK (Laser-Assisted Subepithelial Keratectomy)

    • With LASEK, no incision is made in the cornea, but only the superficial layer (the so-called epithelium) is carefully pushed aside and put back in place after the Excimer laser treatment. LASEK thus combines the advantages of PRK and LASIK.

    • Epi-LASIK (Epithelial Laser in situ Keratomileusis)

    • Epi-LASIK is a further development of the LASEK surgery. In contrast to LASEK, in Epi-LASIK the epithelium is not removed manually with alcohol, but gently pushed aside using a special surgical instrument. After treatment with the Excimer laser, the epithelium is then put back in place and protected with a soft bandage contact lens for three days.

       

    • PRK (Photorefractive Keratectomy)

    • PRK using the Excimer laser currently has the longest experience in correcting visual defects. PRK is now used to treat short-sightedness, astigmatism and long-sightedness. The surgeon carefully removes the superficial corneal tissue (epithelium) under local anaesthetic using drops. Computer-controlled laser pulses are applied with the Excimer laser to the now exposed superficial parts of the cornea, thereby changing the refractive power of the cornea of the eye. The deep cell layers of the cornea remain untouched. The superficial corneal layer regenerates on its own within a few days.

       

    • LASIK (Laser in situ Keratomileusis)

    • In the LASIK procedure, an incision is made in about 1/3 of the thickness of the cornea before the Excimer laser treatment.