How
Does PRK Work?
PRK
(photorefractive keratectomy) was first performed in 1987
in Germany. It is a laser surgical procedure effective in
treating low to moderate degrees of nearsightedness and astigmatism.
PRK is technically simple to perform because there is no corneal
flap created. The surgeon simply wipes away a portion of the
cornea's surface cells (epithelium), and uses the excimer
laser to vaporize away microscopic amounts of corneal tissue.
By modifying the shape of the cornea, light rays are allowed
to focus correctly on the retina to provide clear vision.
The Surgery Experience
Every Nationwide Vision patient undergoes a comprehensive
series of eye tests and examinations and has a consultation.
During the consultation the patient and surgeon discuss and
plan the surgery that best suits the individual patient. On
the day of the surgery, the patient is brought to the laser
surgery suite and positioned upon a comfortable chair that
reclines. Topical anesthetic drops are given to "numb" the
eye for painless correction. Prior to the laser portion of
the procedure, the central portion of the surface epithelium
is removed. The surface epithelium regenerates within a few
days of the surgery. The portion of the cornea below the epithelium
is called stroma. The corneal stroma does not regenerate after
being removed, allowing for precise correction of your refractive
error. During the PRK procedure, the surgeon uses the excimer
laser to remove microscopic amounts of corneal stroma. This
results in a permanent change in the shape of the cornea (which
causes the desired correction of your glasses prescription).
After the surgery is completed, a soft contact lens is placed
on the eye to aid in healing and comfort. It is left in place
for three to four days until the surface epithelium is healed.
What
Should I Expect After Surgery?
It usually takes about one week to achieve crisp and clear
vision after PRK. Although people can see after the surgery,
the vision is not clear until healing is complete in about
one week. The reason for the blurry vision is because the
surface epithelium needs to smooth back as it heals. Most
people experience temporary effects associated with the initial
healing. Increased light sensitivity, glare, halos, dry eyes,
and decreased clarity in dim illumination are common. Most
of these temporary side effects resolve within four to six
weeks after PRK. Complete visual stabilization generally takes
one to four months. Other rare, but possible complications
are discussed with all of our patients during their refractive
assessment appointment.
Discomfort
is more common with PRK than LASIK. People generally have
mild to moderate discomfort for one to two days after PRK,
which is usually relieved by over-the-counter medications
such as Tylenol. A minority of patients experience significant
discomfort, requiring prescription pain relief provided by
your surgeon. This increased discomfort will resolve when
the epithelium (which was wiped away at surgery) heals. This
usually takes 3 to 4 days.
Eye drops required after surgery, but not included in
the cost, may include antibiotic, anti-inflammatory, and
moisturizing drops. Steroid drops are occasionally needed
for prolonged periods to optimize the surgical result.
