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Photo Refractive Keratectomy (PRK)
- What is PRK?
- Am I a suitable candidate?
- How to prepare for PRK?
- How is PRK performed?
- Risk and Complication
- How to take care of my eyes after PRK?
- Follow Up Examination
- FAQ
Back PRK (Photo Refractive Keratectomy) is a refractive surgery to correct low to moderate myopia and astigmatism. For corrections of less than -8.0 dioptres, PRK is highly accurate and the effect is permanent. PRK involves a procedure in which the surface of the cornea is reshaped using an excimer laser. As the corneal curvature is changed, the light rays will focus on the retina to form a sharp image. With the modern technology advancement, PRK is rarely performed except in special cases.
The advantages of LASIK over PRK are minimal postoperative pain, a faster recovery and the larger range of refractive errors that can be treated effectively.
Top In general, suitable candidates:
- Are at least 18 years old
- Are in good general health
- Have no health issues affecting your eyes
- Have no active eye conditions which may affect healing
- Have a stable glasses or contact lens prescription for the last year
Top - Attend one of the public seminars organized by Guy Hugh Chan Refractive Surgery Centre to obtain basic information about refractive surgeries. Admissions are free. Reservation can be made by contacting 2835 8899 or online at www.hksh.com.
- Make an appointment with our Centre for a complete eye examination and evaluation. Book the date of operation if you are suitable for PRK.
- Based on doctor's recommendation, you may receive a scanning examination with Wavefront technology.
- Wear eyeglasses and stop wearing contact lenses before PRK:
- Soft lenses for 3 to 7 days
- Hard or gas permeable lenses for 2 to 4 weeks (Another option: Change to soft lenses for 3 weeks, then stop wearing soft lenses for 1 week)
Top - Anaesthesize the eyes with eye drops.
- Place a speculum to hold the lids apart.
- Use an excimer laser to apply laser with cool ultraviolet light pulses to sculpt the surface of the cornea.
- Place a bandage contact lens on the eye for protection and healing.
- Apply antibiotic and anti-inflammatory eye drops.
Top - Foggy vision in the morning and decreased cornea clarity (corneal haze) which usually improve after a few weeks.
- Dry eyes and photophobia. They will usually subside in a few weeks or up to a few months time.
- Indoor and night vision blur. Halo or glare around light source may be permanent but usually subside after a few months.
- Near vision blur. Reading glasses may be required for patients in presbyopic age.
- Increased light sensitivity, variation of vision or double vision.
- Over-correction, under-correction or induced astigmatism is possible, and which may require further surgery or glasses.
- Irregular healing of the cornea may lead to irregular astigmatism and thus, decrease in best corrected vision.
- Corneal infection or inflammation may occur and lead to astigmatism and overcorrection, and these refractive errors may need further surgery or corrective lenses.
- If incidences occur and cause termination of the procedure, you may need to return on a later day to complete the planned procedure.
- Cornea degeneration is very rare but may lead to corneal transplant. If rejection occurs, it may lead to blindness.
- Other extremely rare complications that may lead to permanent loss of vision, loss of eye, or even loss of life
Top After the Procedure
- Refrain from driving or operating machinery. Take caution with stairs to avoid accidents.
- Close your eyes and rest for 6 hours after going home. Lie on your back while sleeping.
- If a bandage contact lens was placed over your operative eye, do not take it off by yourself.
- Do not press on the operated eye or rub the eyes.
- If there is discomfort in your eyes, you can take the pain-killers provided according to the instructions.
- Do not remove the eye shields until the next day and wipe off excessive tearing outside the eye shields.
- Keep the eye shields on for protection for 1 week when you are sleeping to avoid accidental trauma.
Post-Operative Instructions
- After the treatment, please take medication or instill eye drops as instructed by your doctor.
- No facial, eye make-up, especially mascara, or swimming for 1 month.
- You can put sunglasses on when you are outdoors for 1 month to prevent foreign bodies and irritation of ultraviolet light.
Top - Return for eye examination on the next day, Day 3 or 4, 1 week, 1 month, 3 months and 6 months after surgery or at times your doctor deems necessary.
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