What is Photorefractive keratectomy (PRK)?
Photorefractive keratectomy (PRK) is a well-established laser eye surgery that corrects refractive vision errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. The procedure reshapes the cornea, the clear front surface of the eye, allowing light to be properly focused on the retina, thereby enhancing visual clarity.
Benefits of PRK
- Corrects Various Vision Issues: PRK effectively treats nearsightedness, farsightedness, and astigmatism.
- Suitable for Thin Corneas: Unlike LASIK, which requires a certain corneal thickness, PRK can be an option for patients with thinner corneas.
- Long-term Results: Most patients achieve significant and lasting vision improvement.
Procedure
Preoperative Assessment
Before undergoing PRK, patients must have a comprehensive eye examination. This assessment includes:
- Visual Acuity Test: Determines the clarity of vision.
- Corneal Mapping: Maps the surface of the cornea to identify its shape and thickness.
- Pupil Size Measurement: Assesses the size of the pupil in various lighting conditions.
- Medical History Review: Evaluates any prior eye conditions, surgeries, or medications that could affect the procedure.
The Surgery
PRK is typically performed as an outpatient procedure and involves the following steps:
Preparation: The patient is positioned comfortably, and a local anesthetic is applied to numb the eye.
Removal of the Epithelium: The outer layer of the cornea, known as the epithelium, is gently removed. This can be done using a laser or a special instrument.
Laser Reshaping: A precision laser is employed to reshape the corneal tissue beneath the epithelium. The laser precisely removes microscopic amounts of tissue based on the individual’s specific refractive error.
Repositioning the Epithelium: After the cornea has been reshaped, the epithelial layer is either repositioned or allowed to heal naturally.
Protective Bandage: A soft contact lens may be placed over the eye to promote healing and provide comfort.
Duration
The entire procedure usually takes about 15 to 30 minutes per eye.
Recovery
Immediate Aftercare
After PRK, patients may experience some discomfort, such as a gritty sensation or mild pain. This is typically managed with appropriate aftercare. Patients are advised to:
- Rest: Take time off work or normal activities for at least a few days.
- Avoid Rubbing the Eyes: This helps prevent complications during the healing process.
- Wear Protective Eyewear: Sunglasses can shield the eyes from bright lights and UV rays.
Visual Recovery
Visual recovery after PRK differs from that of other refractive surgeries like LASIK. It may take several days to weeks for vision to stabilize fully. Initially, patients may experience fluctuations in vision quality, which will gradually improve as the cornea heals.
- Follow-up Visits: Regular follow-up appointments are essential to monitor healing and address any concerns.
Photorefractive keratectomy is a reliable and effective procedure for individuals seeking to correct refractive vision errors. By reshaping the cornea, PRK enhances the ability to focus light correctly, resulting in improved visual clarity. Proper patient selection, comprehensive preoperative assessment, and adherence to aftercare instructions are essential for optimal outcomes. As with any surgical procedure, potential candidates should consult with an experienced eye care professional to discuss risks, benefits, and expectations.