The eye is our most important sensory organ. Even today, medicine has not found a way to prevent the natural deterioration of vision. But spectacles, contact lenses or surgery make it possible for almost everyone to see sharply. Everything about the advantages and disadvantages of spectacles, laser and contact lenses.
It's possible thanks to medical and technical advances. Today, an optician or ophthalmologist can help almost everyone with a vision problem. Spectacles, contact lenses and laser surgery are all ways to achieve sharper vision. Each of these options to correct vision weaknesses has its advantages and disadvantages. Here's some information that will help you decide which is best for you:
Spectacles are the most common and effective way to correct a vision problem. Modern, individually customised spectacles are now available for virtually every occasion and every vision need.
They are easy to wear, and modern frames and spectacle lenses make them very comfortable. The high-refraction plastic lenses used today also considerably reduce the weight of strong spectacle lenses. Modern progressive lenses allow wearers to see precisely at all distances. Anti-reflective spectacle lenses prevent annoying light reflections, while self-tinting (also known as photochromic) spectacle lenses darken when exposed to ultraviolet light. Spectacles also help protect your eyes against dirt, dust and insects. There are ideal spectacles for every occasion including work spectacles for those who spend a lot of time on computers or tablet PCs, i.e. those who want comfortable and sharp vision primarily in the near and mid-range distances, which can be customised as needed. The same is true for active applications, such as sport and leisure activities. Special design and production technology now make it possible to produce lenses in your own prescription to fit highly-curved spectacle frames. Special, innovative coatings make even plastic lenses, which used to be rather delicate, into durable precision vision aids.
Spectacle lenses with strong dioptre values can be uncomfortably thick and heavy. They can fog up when you move from the cold outside into the warmth inside. Sometimes spectacles can be unwieldy, for instance when lying on your side, while watching TV or reading. Moreover, the geometry of some spectacle lenses results in areas that appear blurry, which may be more or less pronounced depending on the quality.
The small and practically invisible plastic lenses are the first alternative to spectacles. Modern, and custom-produced contact lenses in particular, allow for precise correction of almost all types of vision problems. There are contact lenses for both short and far-sightedness. The technology is now so advanced that contact lenses are available for presbyopia; these function like progressive lenses on the eye, they are known as multifocal contact lenses.
Contact lenses result in only slight magnification or reduction of the image. Sideways vision is also sharp and is not interrupted by an edge, as can happen with some spectacles. Contact lenses don't fog up, which can be a major factor for some professions – such as sailors, chefs, actors and athletes. Also, different vision impairments in the right and left eye can easily be corrected.
A certain degree of manual dexterity is required to put in contact lenses. Wearing them too long can disrupt oxygen supply to the eye, at the time of purchase ask your optician whether the contact lenses have good oxygen permeability. People who suffer from dry eyes should use hard lenses. In general, tolerability of contact lenses varies greatly from one individual to the next, some people get used to them quickly, while others require more time. Contact lenses require more maintenance than spectacles, this is especially important since incorrect maintenance and contamination can lead to infections. With multifocal contact lenses, some people have issues switching between the far and near range, or require more time to get used to it.
Having laser surgery to correct a vision impairment has been an option for about 20 years. There are a range of procedures, such as Femto-LASIK, LASIK (laser in situ keratomileusis), LASEK (laser-assisted subepithelial keratectomy) and PRK (photorefractive keratectomy), as well as the minimally invasive ReLEx smile treatment method. The physician decides what method is best for each patient. Femto-LASIK is considered the most familiar and is the state-of-the-art procedure. A femtosecond laser is used to cut a thin flap from the cornea, which is then folded to the side. Then the excimer laser ablates the necessary tissue to correct the specific type of vision impairment, all within seconds. In the case of short-sightedness, the cornea is flatter, while it has a more angular shape in the case of far-sightedness. Once the procedure is complete, the flap is folded back into place. Patients can see again sharply shortly after the procedure. The most important requirement for an optimal procedure is that the physician must determine whether it is possible to perform laser surgery at all. The procedure can now be performed on an out-patient basis and usually only takes a few minutes.
The new ReLEx™ smile treatment method from Carl Zeiss Meditec revolutionises laser treatment
Of all the other methods, the new ReLEx smile treatment method from Carl Zeiss Meditec is the first method in which vision impairments can be corrected without having to peel back the corneal flap. This means that the procedure is significantly less invasive for the eye. A laser is used within the intact cornea to create a thin, lens-shaped piece of tissue called a lenticle, which is then removed from under the cornea through an aperture of less than four millimetres. This translates into 80-percent less incision area in the upper layers of the cornea than previously (in LASIK) and a shorter treatment.
No spectacles are required after the surgery. Modern laser correction procedures can even correct presbyopia. Laser surgery can be a good solution for people with vision problems who cannot get used to spectacles or who don't tolerate contact lenses. The dioptre range within which vision impairments can be corrected depends on the procedure used. For instance, ReLEx smile can usually correct short-sightedness of up to minus 10 dioptres. Other requirements: the eye must be fully formed (in general, patients should be over 18 years), the degree of short or far-sightedness (with or without astigmatism) should not have changed within the last two years and the cornea must also be of a certain thickness. With an experienced doctor, this is a very low-risk surgery.
Laser surgery is an invasive procedure performed on an essentially healthy organ. Potential side effects and complications include temporarily dry eyes. These symptoms can last up to twelve weeks. Even if the procedure is successful, the vision impairment may not be completely corrected and it may still be necessary to wear spectacles. Patients with autoimmune disorders should not undergo laser surgery, along with most diabetics, since that condition can cause damage to the cornea. Beware of cheap offers from abroad as they have significant shortcomings.
A relatively new option to correct presbyopia and vision impairments is the implantable multifocal lens. While at first these products were inflexible and rigid, modern models are extremely flexible, foldable and can be implanted in the eye through a tiny incision. The procedure only takes about 10 minutes per eye and can be performed within a few days. It is also completely painless thanks to local anesthetic. During the procedure, the multifocal lens is usually placed in the capsular sac, directly behind the pupil, and held in place using a haptic anchor. A new technology has optimised the structuring of the near, mid and far-range zones, significantly increasing visual acuity in all ranges and reducing the risk of glare to a minimum.
The new generation of multifocal lenses is very well tolerated and does not cause pain or discomfort due to the feeling of having a foreign body in your eye. They are primarily implanted in individuals who suffer from age-related cataracts. Around 20 million people worldwide undergo cataract surgery every year. Clinical studies show that 90 percent of patients no longer require a visual aid at any time after the surgery. The operation lasts for a lifetime and it is no longer necessary to have a follow-up procedure since the refraction values generally remain stable. Patients can perform any kind of daily task and even play sports.
Patients suffering from certain pathological changes in the eye are not eligible for the procedure. If a patient has this kind of eye disorder, any potential cataract operation will be discussed with the ophthalmologist during the consultation.
Our eyes are our most important sense organ. And since each eye is as unique as a fingerprint, it requires a customised visual analysis at your optometrist.
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