PRK (Photo Refractive Keratomileusis) is very similar to LASIK in that it is also a Laser driven procedure used to correct a patient’s vision. PRK has been around longer than the LASIK procedure and has been performed on thousands of patients worldwide.

What is PRK?

PRK is a procedure performed on the outer layer of the eye. It differs from LASIK in that the patient does NOT have a flap created. Instead, a tiny amount of tissue is removed from the cornea (this layer is called the epithelium); this layer grows back in approximately four days. Once this layer is removed, the excimer laser treats the inner tissue of the cornea to give the patient the corrected vision they desire. A contact lens is placed over the cornea to help protect the eye while it heals.

The cornea helps focus light to create an image on the back of the eye (the retina). The eye works much like a camera; the cornea is similar to a lens in the camera which focuses light to create the image on the film (the retina). It is very common to have an unusual shaped cornea and because of this, the image trying to target the retinal is out-of-focus (blurred). These imperfections in the cornea are called refractive errors. PRK helps reshape the cornea and rid the refractive errors so a patient can see clearly.

Types of Refractive Errors and Correction

There are three types of refractive errors:

1. Myopia (nearsightedness) & Correcting For Distance: persons with myopia have a harder time seeing objects in the distance but can usually see up close. LASIK is most commonly used to correct a patient’s vision to see better in the distance. This usually requires operating on both eyes. At Morris Eye Group we operate on both eyes on the same day.
2. Hyperopia (farsightedness): persons with hyperopia can see objects in the distance but not up close.
3. Astigmatism: a person with astigmatism usually sees blurred objects due to the shape of their eye. A person with astigmatism has an eye shaped like a football which elongates images. A person with no astigmatism has an eye that is shaped like a basketball. It is possible, and common, to have an astigmatism and be nearsighted or farsighted. In the past, lasers were not advanced enough to correct astigmatism. However, at Morris Eye Group our Custom Laser allows for us to correct astigmatism. This can be corrected on its own or in conjunction with nearsightedness or farsightedness.
4. Presbyopia: Presbyopia is a condition that affects most individuals around the age of 45. Presbyopia is a condition that occurs when the muscles inside the eye stop moving the lens back and fourth. This causes a patient to need reading glasses. A patient with presbyiopia can need correction for both distance and near vision. At Morris Eye Group we have the ability to help patients looking to achieve good vision for the distance and up close for reading. The only way to accomplish this through laser vision correction is by performing monovision. (Monovision is a technique where the patients dominate eye is corrected for the distance and the non-dominate eye is corrected for reading. The brain learns to use both eyes together so the patient can see far away and up close.  Patients first try this with contact lenses to make sure they like the vision, and then it can be performed through LASIK.)

PRK Is For Those Who:

1. Are at least 18 years of age
2. Have had a stable eye prescription for at least one year
3. Want to reduce or eliminate their dependence on glasses or contact lenses
4. For those with thinner corneas
5. Have occupations that may require this procedure (for example some military occupations)
6. Have been approved through a thorough exam with one of our doctors

Appointments

Complimentary Consultation: At Morris Eye Group we offer different techniques for accomplishing Laser Vision Correction. We offer a complimentary consultation to help determine what procedure(s) would be best for the patient.  At this visit, the patient has a vision exam as well as topographical imaging of the cornea. These measurements help the doctor to understand the patient’s vision and what options are available to accomplish the patient’s visual goals. The doctor examines the patient and goes over all vision correcting options. If the patient is deemed a candidate for PRK, or another procedure, all other appointments are then scheduled.

Pre-Operative Appointment: At Morris Eye Group we do a very through exam with the patient to rule out any possible reasons a patient would not qualify for a procedure.  The information and tests we perform include: health history, automated refraction, full refraction, topography of the eye, pachymetry reading, visual acuity exam, dry eye test, dilated exam, cycloplegic refraction and exam, and discussion with the doctor. The patient is given post operative instructions, eye drops and appointment times.

Procedure Day:  On the procedure day, the patient will need a driver and can expect to be at our office for an hour and a half.  The procedure itself only takes about twenty minutes.  At the patient’s request, and doctor’s approval, an oral sedative may be given to assist with anxiety prior to the procedure. After the patient is been prepped the doctor will remove some of the top layer of tissue on the cornea, the laser treatment will be applied and after the laser a medical contact lens will be placed on the eye to help the eye heal faster. Fifteen minutes following the procedure, the doctor will check the patient’s eyes and the patient will be discharged.  After the procedure, most patients go home and relax or take a nap. Most patients that have PRK can see well within a week of the procedure and can expect to have gradual improvement in vision over the course of a few weeks.

Post-Operative Care: We see the patient three days after the PRK procedure for the first post-operative appointment. If the eye is healed enough, the contact lens is removed at this appointment. The patient can expect to have other post-operative appointments in the following weeks after the procedure is complete.