Introduction to LASEK and PRK Surgeries for Correcting Refractive Errors

LASEK and PRK are another commonly used method for the treatment of refractive errors and astigmatism, myopia (nearsightedness), and hyperopia (farsightedness) all over the world; the most important difference between these methods with LASIK is the location of excimer radiation on the cornea. In LASIK, after peeling the surface of the cornea, the laser radiation reaches the new layer and peeling is carried out, while in LASEK surgery, without peeling the cornea and just after removing the corneal epithelium, which is the outermost layer of the cornea layer, the laser radiation reaches the cornea surface. On the other hand, LASEK surgery is introduced as the modified type of PRK surgery; nevertheless, it is less popular than the PRK method. In the PRK (Photorefractive Keratectomy) method, the patient's degree of nearsightedness is reduced using excimer laser radiation. By this method, a very thin layer of the cornea, at a rate of a few tens of microns is removed; and the rate of refractive errors in the eye is reduced by applying changes to the corneal curvature.

This is an outpatient surgery treatment and is performed in the clinic. The patient's eye is first numbed through using local anesthetic drop; then, after the removal of the outer corneal surface (epithelium), the surgeon begins the procedure by excimer laser; and finally, the surgery is stopped after reformation of the cornea. After the end of the surgery, the ophthalmologist usually uses a contact lens to cover the cornea surface until the surface is restored. Then, the patient receives antibiotic drops for a week and corticosteroid for a few months. In NOOR Eye Hospital and its ophthalmic centers, for patients with myopia with the diameter of 4 to 7 diopters, Mitomycin is applied to the surgery site after PRK surgery; according to the performed studies, this leads to improving the outcomes of the surgery and significant reduction in the likelihood of the corneal opacity.

* Note: Given the evaluation of the patient’s clinical conditions and specific examinations, the ophthalmologist recommends the best and most efficient treatment method.

In LASEK Surgery:

1. Eye dryness due to surgery is much less than other methods.

2. Corneal damage in this method is much less than other methods, in particular LASIK surgery.

3. Surgery duration is short and about a few minutes.

4. Corneal nerves are less damaged.

In PRK Surgery:

1. Short duration of surgery compared to LASIK surgery

2. No intraoperative flap complications

3. No need for Microkeratome and related technology

4. No deep corneal inflammation

5. Possibility of surgery in thin corneas

Possible Complications:

Each of the commonly used methods for treating refractive errors has common or rare complications. This is completely natural and will not occur in many cases or will be gradually resolved after occurrence. The treatment team of Noor Eye Hospital and its ophthalmologic centers provides more information to all patients.

Possible Complications of LASEK Surgery:

1. Feeling of a foreign body in the eye, one to four days after the LASEK surgery

2. Possibility of reduced vision under poorly light conditions even up to 12 months after the surgery

3. Dry eyes, and need of using moisturizing drops

4. Hazy or cloudy vision until a few months after the surgery

Complications of PRK Surgery:

1. Sensitivity to light, which may last for several months

2. Feeling of glare or halos around light sources, especially noticeable at night

3. Changes in daytime vision that may last up to 6 months after the surgery

4. The possibility of corneal infection

5. Corneal scarring

6. Probability of corneal haze

1. People with too gradient and thin cornea are good options for LASEK surgery, and LASIK surgery is very difficult for them.

2. People exposed to high-risk jobs or activities, such as boxing athletes

3. People with dry eye syndrome

1. Wash eyelids and lashes before surgery.

2. Do not makeup 48 hours before surgery.

3. Wear light clothing on the day of surgery.

4. Do not use perfume and cosmetics on the day of surgery.

5. Do not use non-contact lenses 48 hours before surgery.

6. Use a sedative if you have anxiety.

Patient's preparation during surgery:

1. LASEK and PRK surgeries are not painful, and your cooperation plays a very important role in achieving the right result. So stay calm and pay attention to your doctor's instructions during surgery.

2. Look at the red or green light during the surgery and avoid moving your eyes and head.

3. The duration of the laser, depending on what type of laser is used, is less than one minute and usually about 10 seconds. So do not move the eyes during the time you hear the laser sound.

4. Do not worry about blinking during surgery because your eyelids are opened by a device. It is better to prevent pain, avoid pushing your eyelids and frowning.

5. To prevent infection before, during and after surgery do not touch your eyes as it causes contamination.

Note: During the early hours of the postoperative period, you may feel severe pain that oral medications and eye drops are prescribed to reduce it. Also, in the first few days after the surgery, you experience tears, burning, feeling foreign body in the eye, blurred vision, and sensitivity to light. At these days, it is necessary to rest at home until corneal epithelium is restored. This is an average of 5 days, but it may be longer. After epithelium wound repair, your vision gradually begins to improve, but your first vision determination will be 4 weeks after the surgery. In some cases, it is necessary to wait 10 to 15 weeks after the surgery to reach the final vision.

 

After the surgery, for ensuring the treatment result, the ophthalmologist will prescribe medications including betamethasone drops, chloramphenicol, Dicloptin or Biofenac, Fluorometholone and artificial tears. Note that the abovementioned prescription is a general one and changes may be made to it, depending on the doctor's diagnosis; nevertheless, it is necessary for the patient to take medication according to the order. Keep in mind that bathing and washing the eyes are allowed after the restoration of epithelium (averagely after 4 days) and removing the therapeutic contact lens (TCL). Meanwhile, wearing sunglasses, especially after PRK, is advised for at least 3 months and even more in the outside environment.

Note: Arbitrary use of ophthalmic drugs can be accompanied by severe and irreversible complications.

Postoperative Essential Cares

1. On the day after surgery, you are visited by the surgeon; during this visit, the doctor presents the medication orders in accordance with the findings of the examination.

2. If you do not feel much pain, you may cautiously start daily activities.

3. Avoid driving.

4. Be sure to refer to your ophthalmologist on the second, third and fourth day, and receive new orders. Note that in case of complete restoration of your corneal epithelium repairs, the ophthalmologist will remove the contact lens from your eye.

5. Washing face and bathing are allowed after removal of the contact lens.

6. Swimming is forbidden for at least 3 weeks.

7. Eye makeup is forbidden until one week after surgery.

8. It is possible to do light exercises at the end of the first week.

Order of Postoperative Examinations

1. Every day until the contact lens is removed.

2. A month after surgery

3. Three months after surgery

4. One year after surgery

5. Performing annual examinations

Is astigmatism treated with LASEK and PRK surgery?

What are patient’s general conditions for PRC and LASEK surgery?

Is this surgery painful?

What is the approximate duration of the surgery?

I use contact lens. Can I have LASEK and PRK surgery?

Does the patient’s eyes contact with water after the surgery affect the outcome of the surgery and the quality of treatment?

 

Is astigmatism treated with LASEK and PRK surgery?

Yes, if you are nearsightedness, farsightedness or astigmatic, you can use this method. Of course, you should be carefully examined by an ophthalmologist before taking any action. Other treatments may be appropriate for you.

What are patient’s general conditions for PRC and LASEK surgery?

• Being at least 18 years of age

• Presence of refractive errors

• No change in the patient's eye score for at least one year or just 0.25 for 18 months

Is this surgery painful?

No, it is painless. Local anesthetic drops are used for numbness and no injection is performed.

What is the approximate duration of the surgery?

It takes about 5 minutes to perform the surgery; however, it takes about two hours for preparation time and postoperative care.

I use contact lens. Can I have LASEK and PRK surgery?

Your ophthalmologist should determine it; nevertheless, if you have continuous and prolonged contact lens use, it is better not to use the soft lens two weeks before the surgery and hard lens one month before the surgery.

Does the patient’s eyes contact with water after the surgery affect the outcome of the surgery and the quality of treatment?

Yes, for the same reason, we recommend not swimming for three weeks after the surgery. Furthermore, using soap and shampoos when bathing as well as cosmetics is forbidden until two weeks after the surgery.