Ideal candidates for refractive surgery are healthy people aged 18 and older with healthy eyes that are not content to wear glasses or contact lenses.

The refractive corneal surgery changes the corneal curvature so that light beams are precisely focused on the retina. The aim of refractive surgery is to reduce dependency on glasses or contact lenses. For most people who undergo a refractive surgery, this goal is achieved. Around 95% thereafter need no correction in the distance more. Ideal candidates for refractive surgery are healthy people aged 18 and older with healthy eyes that are not content to wear glasses or contact lenses. Among the contraindications for refractive surgery are currently existing eye diseases, including very dry eyes autoimmune or connective tissue disease that can affect wound healing, the use of isotretinoin or amiodarone Refraction should be stable for at least 1 year prior to surgery. Patients should be informed that can be reactivated by engaging a latent herpes simplex virus infection. The adverse side effects of refractive surgery are temporary symptoms of foreign body sensation gloss halos drought occasionally experience these symptoms. Among the possible complications include overcorrection undercorrection infection Irregular Astigmatism After an excimer laser treatment of superficial corneal stroma is a delicate haze (Haze) may form. When the central cornea permanently altered by an infection, an irregular astigmatism or cloudiness, also the best corrected visual acuity is worse. With careful preoperative selection of patients, the overall complication rate is low and the likelihood of vision loss is <1%. Kinds of refractive surgery The two most common method of refractive surgery is laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK) Lasik (LASIK) In a LASIK a corneal flap (flap) is reacted with a femtosecond generating laser or a mechanical microkeratome. The flap is folded back and the underlying stromal bed located is formed with an excimer laser (photoabladiert). The flap is then repositioned without seam. Since the surface epithelium intact remains central, vision recovered quickly. Most patients notice the next day, a significant improvement in their visual acuity. LASIK can be used to correct myopia, hyperopia and astigmatism. Benefits of LASIK compared to PRK are a - desired - less wound healing response of the central stoma (since the central corneal epithelium is not removed, reducing the risk of central haze development during healing), a shorter recovery time and minimal postoperative pain. Disadvantages include possible intraoperative and postoperative Flapkomplikationen as irregularities of the flap, the dislocation of the flap and long-term corneal ectasia. Ectasia occurs when the cornea has become so thin that the intraocular pressure causes instability and a bulging of the thinned and weakened corneal stroma. This can blurred vision, increased myopia and irregular astigmatism resultieren.Photorefraktive keratectomy (PRK) In PRK, the corneal epithelium is removed and then the excimer laser used to form the front curve of the corneal Stromabetts. The PRK is used to treat myopia, hyperopia and astigmatism. The epithelium takes 3-4 days for regeneration in general; during which time a bandage contact lens is worn. In contrast to LASIK, no corneal flap is created. The PRK may be better suited for patients with thin corneas or front Basalmembrandystrophie. Advantages of PRK include a total of a thicker Residualstromabett, thereby reducing the risk of ectasia, but not eliminated, and the lack of complications associated with the corneal flap. Disadvantages include the risk of corneal opacity (haze) when removed a large amount of corneal tissue and the need for postoperative Corticosteroidtropfen for 3 months. The intraocular pressure postoperative patients using topical corticosteroids, should be carefully monitored as glaucoma induced by corticosteroid been observed after PRK ist.Intrakorneale ring segments (INTACS) Intracorneal ring segments (INTACS) are thin arcuate segments of biocompatible plastic, the small pairs by a radial Hornhautinzision be implanted deep into the peripheral corneal stroma (approximately two thirds of the layer thickness). By Intacs implantation the central corneal curvature is flattened, reducing myopia. INTACS be used for the treatment of mild myopia (<3 dpt) and a minimum astigmatism (<1 D). Since the two INTACS segments are placed in the corneal periphery, the central optical zone remains free. Intacs can be replaced or removed when necessary. Risks (induction of) astigmatism, under and over correction, infection, glare, halos and placement in the wrong depth. Currently Intacs are mostly used for the treatment of dilated cornea diseases such as keratoconus and post-LASIK ectasia when glasses or contact lenses do not provide adequate visual acuity more or are uncomfortable. improve the best-corrected visual acuity and contact lens tolerance at 70-80% of Patienten.Phake intraocular lenses (IOLs) Phakic intraocular lenses (IOL) are lens implants that are used to treat severe myopia in patients who are not suitable candidates for laser corrections. Unlike cataract surgery, the patient's natural lens is not removed. The phakic IOL is inserted into the eye through an incision just in front of or behind the iris. This process represents an intraocular surgery and must be performed in an operating room. The risks include cataracts, glaucoma, infection, inflammation and loss of corneal endothelial cells with subsequent chronic corneal edema, which eventually becomes symptomatic. Since phakic IOL astigmatism not correct, the patient a subsequent laser correction can undergo in order to improve the refractive results in a technique known as Bioptik. Since the majority of myopia is corrected by the phakic IOL, is less corneal tissue removed by the excimer laser and the risk of ectasia is thus gering.Clear-Lensektomie A Clear-Lensektomie may occur in patients with high hyperopia already presbyopic, in be considered. This procedure is identical to cataract surgery, other than the patient's lens is clear and not cloudy due to cataract. A multifocal or accommodating IOL that allows the patient to focus without external lens correction over a wide range of distances can be used. The main risks of a clear-Lensektomie are infections and a rupture of the posterior capsule, which would require another operation. A Clear-Lensektomie should be done with great caution in young patients with myopia, as it is an increased risk of postoperative retinal detachment haben.RadiƤre keratotomy and astigmatic keratotomy In the methods of radial and astigmatic keratotomy corneal shape affected by deep cuts with a diamond knife. The radial keratotomy was replaced by the laser correction and is rarely used because it offers no clear advantages over laser vision correction, has a greater need for subsequent post-treatments, can lead to visual and refractive results that change throughout the day and long-term can cause Hyperopieverschiebung. An astigmatic keratotomy is still often performed at the time of cataract surgery. The incisions are referred to as limbusrelaxierende incisions because the optical zone is substantially larger and closer to the limbus.


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