Photorefractive keratectomy or PRK is a kind of laser refractive surgery that can help to correct the problems of myopia (nearsightedness), hyperopia(farsightedness) and astigmatism. PRK was the first kind of laser eye surgery that had been performed much longer than LASIK for visi correction. Though it might require longer time to recover from PRK than LASIK, PRK has several benefits over LASIK in patients.
Unlike LASIK and other kinds of laser eye surgery, PRK works by reshaping cornea with an excimer laser that allow light to enter the eyes and focus properly onto the retina for clear vision without wearing eye glasses or contact lenses.
The major difference between PRK and LASIK has been discussed below.
In case of LASIK, there is a thin flap formed on the cornea by using a femtosecond laser or microkeratome. This flap can be lifted to expose corneal tissue and replaced after the cornea gets reshaped through an excimer laser.
In PRK, the thin outer layer of cornea known as epithelium has to be removed and discarded before reshaping the corneal tissue with the use of excimer laser. The epithelium gets rired within a few days after the surgery is done.
PRK versus LASIK
The results of PRK surgery can be compared with LASIK outcomes though initial PRK recovery seem to be slower as it takes a few days for the new epithelial cells to regenerate and thus, cover your eye surface. There is slightly increased risk of eye infection and vision blurriness in the first few days after performing PRK surgery.
LASIK patients usually get less discomfort and their vision problem stabilizes more quickly while vision improvement with PRK is gradual and the outcome may require several we However, PRK provides some distinct benefits.
Since no LASIK-style corneal flap has been made during the PRK, there is more corneal thickness for the treatment. This is beneficial when the corneas become very thin for LASIK. There isn’t any risk involved with flap complications and the chances of removing too much of cornea through excimer laser gets lessened.
About PRK procedure
There are three steps involved with a PRK procedure:
- The central area of corneal epithelium gets remved by using alcohol solution which is a surgical instrument or “buffing” device.
- An excimer laser can be used to reshape curvature of the cornea precisely. This is a highly specialised and computer-controlled laser which delivers certain pulses of ultraviolet light that can remove microscopic amounts of the tissue in an accurate way.
- A soft contact lens is generally placed on your cornea that can protect eyes when new epithelial cells grow on corneal surface. The method requires nearly four or e days after which contact lens can be removed by your eye specialist.
What you can expect
Before PRK: You need to select an eye surgeon who has good experience in PRK surgery. After this, you have to perform an eye examination and find out if you are the right candidat for laser eye surgery. This includes a thorough assessment of:
- Size of your pupils.
- Thickness of the corneas.
- Moistness of the eyes in order to detect the risk of formingdry eyes after laser eye surgery and treat them accordingly.
- Corneal curvature with a corneal mapping device that can measure contours of the front surface of your eyes.
The eye doctor will evaluate your health condition and medical background, as well as any medications you take to know if you are the right candidate for PRK. When you wear contact lenses, it is important to stop wearing them for a certain time before performing eye examination. This is because contacts may changenatural shape of your cornea and so, it is always best to consult with the eye doctor for more details related to your eyes.
LASIK in London is a popular option though PRK has exceptional benefits.
During PRK: PRK eye surgery usually uires 15 minutes only for both the eyes. You will have to stay awake during the procedure but your eye surgeon might provide with a mild oral sedative to make you feel relaxed.
Numbing eye drops can be applied to your eyes and an instrument known as a lid speculum is used to keep eyelids open. Your eye surgeon will direct excimer laser over the eyes that has been programmedaccording to the prescription.
You need to look at the target light for a short time when the surgeon keeps a keen watch on your eyes with the help of a microscope as laser sends pulses of light to your cornea.
The laser energy can reshape your cornea and removes microscopic amounts of tissue. Most people do not suffer from any kind of discomfort, though there might be some pressure on your eyes. Your surgeon has complete control of the laser and may turn it off at any time.
Your eye surgeon will cover treated corneby using bandage contact lens. The epithelial cells will be growing within a few days and bandage contact gets removed.
Immediately After PRK: You need to take rest for a short period after the surgery and then return home. The eye surgeon will prescribe topical antibiotics, anti-inflammatory and pain medications to lessen post-operative discomfort, reduce swelling and speed up healing process. You have to attend follow-up appointments with your doctor often over the next several weeks to evaluate your healing process.
Full recovery from PRK: It will require longer time for your vision to recover after PRK when compared to LASIK surgery. It might be a few days to a couple of weeks before you feel satisfied with visual acuity and even more for vision to stabilize completely.
Most PRK patients usually can get back to driving a car one to three weeks after the surgery, however it may take almost three months before your vision becomes clear fully.
Long-term PRK outcomes
The results of PRK and are quite similard most people can attain 20/20 vision after the PRK surgery. Almost all patients will be able to achieve 20/40 visual acuity or better.
If the sensitivity to light seems to be a problem after PRK, then eyeglasses having photochromic lenses will be able to offer relief. In case you are having minor residual refrace error after surgery, low-power prescription lenses with anti-reflective coating may sharpen your vision for activities such as night driving.
Both LASIK and PRK complications seem to be rare and may include infection as well as glare that can be noticed when viewing lights at night or while driving. you might require enhancement surgery to improve vision further or correct gradual worsening of your eyesight over time. Reading glasses will probably be needed after performing PRK surgery when you are in the 40s due to age-related loss of near vision known as presbyopia.