Radial Keratotomy or RK and Photorefractive Keratectomy or PRK are other refractive surgeries used to reshape the cornea. In RK, a very sharp knife is used to cut slits in the cornea changing its shape. PRK was the first surgical procedure developed to reshape the cornea, by sculpting, using a laser. Later, LASIK was developed. The same type of laser is used for LASIK and PRK. Often the exact same laser is used for the two types of surgery. The major difference between the two surgeries is the way that the stroma, the middle layer of the cornea, is exposed before it is vaporized with the laser. In PRK, the top layer of the cornea, called the epithelium, is scraped away to expose the stromal layer underneath. In LASIK, a flap is cut in the stromal layer and the flap is folded back.
Phakic intraocular lenses, or phakic lenses, are lenses made of plastic or silicone that are implanted into the eye permanently to reduce a person's need for glasses or contact lenses. Phakic refers to the fact that the lens is implanted into the eye without removing the eye's natural lens. During phakic lens implantation surgery, a small incision is made in the front of the eye. The phakic lens is inserted through the incision and placed just in front of or just behind the iris.
What do they treat?
Phakic lenses are used to correct refractive errors, errors in the eye's focusing power. All phakic lenses approved by the FDA are for the correction of nearsightedness (myopia).
A medical laser used in LASIK and other vision correction surgery. Excimer lasers use very short pulses of ultraviolet (UV) rays to ablate (vaporize) tissue to reshape the cornea, enabling the eye to better focus light. The duration of each pulse of an excimer laser is measured in nanoseconds. A nanosecond is one-billionth of a second.
PRK (or photorefractive keratectomy) is the second most popular laser eye surgery in the Jordan, behind LASIK. The question of PRK Vs LASIK is common for consumers interested in laser vision correction.
Like LASIK, PRK uses an excimer laser to reshape the cornea. But in PRK, no corneal flap is created with a microkeratome or femtosecond laser prior to the corneal reshaping.
Instead, the central portion of the thin outer layer of the cornea (the epithelium) is removed from the eye, usually after being loosened with a dilute alcohol solution. The excimer laser treatment is then applied to the underlying corneal tissue (the stroma) to reshape the eye.
A cataract is an eye disease in which the normally clear lens of the eye becomes cloudy or opaque, causing a decrease in vision. The lens is important for focusing light onto the back of the eye (the retina) so that images appear clear and without distortion, and the clouding of this lens during cataract formation distorts our vision. Cataracts are usually a very gradual process of normal aging but can occasionally develop rapidly. They commonly affect both eyes, but it is not uncommon for a cataract in one eye to advance more rapidly. Cataracts are very common, affecting roughly 60% of people over the age of 60 .
Used to correct refractive errors, LASIK eye surgery is a treatment that reshapes the cornea in order to produce clear vision. The LASIK refractive eye surgery procedure can treat myopia (nearsightedness), hyperopia (farsightedness), and astigmatism, and reduce patients’ dependency on contact lenses and corrective lenses. Because refractive errors impede the focusing ability of the eye, patients who suffer from these conditions experience blurred vision. LASIK eye surgery provides these individuals with an effective treatment option.
Procedure
To determine whether or not a patient is a good candidate for LASIK eye surgery, the ophthalmologist will conduct a pre-LASIK eye examination. Once completed, patients should follow certain guidelines in the days and weeks preceding LASIK vision correction.
1. How is it possible to change the color of the eye?
An intraocular implant is placed in the anterior chamber of the eye to change the appearance of the iris.
Medically, it can be used in patients with iris abnormalities such as ocular albinism, coloboma, total/partial aniridia as well as heterochromia and iris atrophy. These implants are able to decrease photophobia and project the form of a healthy iris for patients with irregular iris appearance.
The implants are also available as a way for healthy and safe individuals to alter their eye color and serves as an alternative to colored contact lenses for those wishing to achieve permanent cosmetic results.