PRK Overview
Photorefractive keratectomy, commonly known as PRK, was the first laser refractive surgery approved by the FDA and has been performed for over 15 years. During PRK, the surgeon reshapes the outer surface of the cornea with an excimer laser, which is an ultraviolet light beam used to precisely remove tissue. By resculpting the corneal tissue, light focuses better into the eye, resulting in clearer vision. Excimer lasers can also be used to correct astigmatism by smoothing the surface of cornea to a more normal shape. PRK differs from LASIK in that no corneal flap is created prior to resculpting the cornea with the excimer laser so the cornea itself is not disturbed. Since PRK does not involve creating a corneal flap, there is quicker recovery with respect to dry eye. Vision improvement is gradual and can take a few days up to 6 months. Surgeons generally recommend PRK for people with thin corneas or moderately dry eyes.
PRK Procedure
Dr. Jani will use an excimer laser to reshape the cornea to your precise correction. Prior to applying the laser treatment, the surface cells (epithelium) of the cornea are gently removed; this may be done with a microsurgical eye instrument in conjunction with a dilute chemical solution. The laser treatment typically lasts 30 seconds or less depending upon the amount of correction desired. A soft contact lens is temporarily placed on the cornea to protect the eye and promote comfort and healing of the epithelium. The surgeon will remove this lens during post-operative care after 4-7 days.
The outer layer of the cornea, or epithelium, is a soft, rapidly regrowing layer that regenerates within a few days with no loss of clarity. The deeper layers of the cornea, as opposed to the outer epithelium, have very limited regenerative capacity.
A computer system tracks the patient’s eye position redirecting laser pulses for precise placement. Most modern lasers will automatically center on the patient’s visual axis and will pause if the eye moves out of range and then resume once patient’s eye is re-centered.
PRK Recovery
Post-operatively, PRK will result in some discomfort. The soft contact lens placed after the procedure along with antibiotic eye drops help healing significantly. Over-the-counter pain relievers and cold compresses may also be helpful to relieve any discomfort. Make up and lotions should be avoided around the eyes until the soft contact lens is removed.
Post-operatively, PRK will result in some discomfort. The soft contact lens placed after the procedure along with antibiotic eye drops help healing significantly. Over-the-counter pain relievers and cold compresses may also be helpful to relieve any discomfort. Make up and lotions should be avoided around the eyes until the soft contact lens is removed.
PRK versus LASIK
Unlike LASIK, PRK does not carry the risk of a corneal flap dislocation, which may occur (especially with trauma) at any time after LASIK.
For many patients, PRK is a safe, viable alternative to LASIK. Long term studies demonstrate that PRK and LASIK are very equivalent procedures in so far as vision is concerned. The primary difference is the speed of visual recovery. Additionally, PRK recovery is more uncomfortable for the first 2-3 days after the procedure.
Candidates for PRK
By undergoing a comprehensive eye exam, our surgeon, Dr. Jani, will be able to determine if you are an ideal candidate for PRK. Some of the attributes to good candidacy for PRK include:
- Adequate corneal thickness
- A stable eye prescription for at least 12 months
- Good physical and ocular health
- Realistic expectations regarding results of laser vision correction
- Understand the risks and benefits of PRK
- Not a good candidate for LASIK
PRK Risks
As with any surgery, there are some risks involved. Some risks associated with PRK that can be temporary or permanent include:
- Dry eyes
- Persistent glare and / or halos
- Under or over-correction
- Recurrence of myopia, hyperopia, or astigmatism
- Corneal haze
- Scarring
- Pain
- Prolonged epithelial healing period
- Reduced best corrected visual acuity
- Reduced acuity in low light
As with all types of refractive surgery, including LASIK, dry eyes is one of the common risks of PRK surgery and can be permanent. PRK may be performed on one eye at a time to assess the results of the procedure and ensure adequate vision during the healing process if the patient desires. Some activities requiring good binocular vision may have to be suspended between surgeries and during healing periods.
Some PRK patients have complained of glare and halos, but many times these symptoms are resolved after a few months as part of the healing process. Under / over correction of the refractive error is possible, especially with more severe myopia, hyperopia, or astigmatism since the predictability of healing becomes less exact.
PRK FAQs
Should I Consider PRK Instead Of LASIK?
Surgeons generally recommend PRK for people with thin corneas or moderately dry eyes.
Other reasons may be concern for trauma to the eye after laser vision correction due to occupational hazards or the desire to have laser vision correction with no corneal flap.
Call us to explore your options towards visual freedom. Consider laser vision correction and schedule a free consultation with Dr. Jani, a fellowship trained laser vision correction and cornea specialist. After all your eyes are too important to trust to just anyone! Please contact Vista Eye for more information about laser vision correction, or to schedule an appointment today.
