Updated on  February 20, 2024
8 min read

The Significance of the LASIK Flap in Laser Eye Surgery

9 sources cited
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Key Takeaways

  • LASIK (laser in-situ keratomileusis) surgery involves the creation of a flap (LASIK flap) and corneal reshaping using an excimer laser.
  • A LASIK flap is a piece of cornea cut on the surface layers of the cornea. It’s folded back to expose the underlying tissues and allows for laser treatment.
  • The LASIK flap is created using a device known as a microkeratome blade or a less-invasive device, the IntraLase® laser.
  • After LASIK surgery, the flap requires proper care to avoid complications such as dislodging, infections, folding, drying, inflammation, or epithelial ingrowth.
  • Doctors recommend people avoid water contact, intense activity, rubbing eyes, wearing makeup, or skipping medication during the healing period.
  • Doctors also recommend follow-up visits to ensure close monitoring of the healing process.

LASIK Surgery Overview

Laser in-situ keratomileusis, or LASIK eye surgery, is a refractive vision correction treatment for:

LASIK surgery involves creating a corneal flap. Surgeons do this by using a sharp blade device known as a microkeratome and an excimer laser to reshape the cornea. 

The cornea is the clear front part that focuses light on the retina, which enables you to see. Reshaping the cornea enhances its focus on the retina and results in improved visual acuity.

LASIK outcome studies have proven the procedure is a safe alternative to prescription glasses and contact lenses.1

LASIK outcome studies also indicate that 96 percent of LASIK patients achieve satisfactory outcomes after full recovery.2

Over the years, LASIK surgery has seen improvements to promote safe outcomes. 

Notable traditional LASIK improvements include epithelial LASIK (Epi-LASIK) and IntraLase LASIK (iLASIK).

What is the LASIK Flap? How is it Made?

The LASIK flap is a piece of cornea cut with high precision and folded back to allow for laser treatment. The process involves a blade device known as a microkeratome.3

Recent developments have introduced laser-guided flap creation as an alternative. This reduces the complications of handheld microtomes, such as: 

  • Irregular cuts
  • Incomplete or partial flaps
  • Buttonholes
  • Epithelial damage

IntraLase LASIK or iLASIK is the most recent advancement that doesn’t use a handheld blade for flap creation. 

Instead, iLASIK uses a femtosecond laser to create the flap. This makes it easy, accurate, and results in fewer flap complications.

LASIK Flap Procedure

Creating the LASIK flap is a quick outpatient procedure. The entire LASIK surgery takes about 30 minutes or less. 

During traditional LASIK surgery, you sit in a reclining chair. After examination, your doctor will use a microkeratome to cut a piece of your cornea, which leaves a hinge to hold it in place.  

Your surgeon will then fold the flap back to expose the inner corneal tissue for excimer laser treatment.

If you’re under iLASIK surgery, your surgeon will use a laser device known as an IntraLase® laser to create the flap. 

The IntraLase® laser produces rapid pulses of laser light, creating a layer of bubbles under the cornea. The bubbles allow your surgeon to lift the thin corneal flap. Then they fold it back to allow for wavefront-guided vision correction.

Both treatments involve an excimer laser, which is an ultraviolet (UV) laser that reshapes the cornea.

Post-Treatment Care

After laser treatment, your doctor will reposition the flap and smooth it out to get rid of bubbles.

Luckily, no bandages are required. Instead, your doctor will prescribe pain medications and lubricating eye drops to ease any discomfort after surgery.

LASIK Flap Recovery & Aftercare

After LASIK surgery, you’ll need to take good care of your eyes to avoid irritating, dislodging, or infecting the treated area. Your doctor will give you post-op care guidelines.

For most people, the flap will be nearly healed within 24 hours. Normal activities can resume after about a week of healing. However, it may take up to 3 months for the flap to recover fully.

Visit your eye doctor frequently for close monitoring during this time.

LASIK Flap Complications 

LASIK flap related complications include:

Epithelial Ingrowth

This is the development of epithelial tissue underneath the corneal flap. It can cause eye pain, sensitivity to light, or blurry vision. 

Your surgeon can correct epithelial ingrowth by lifting the flap and removing the ingrown tissue.

Corneal Ectasia

Corneal ectasia is a condition characterized by thinning of the cornea. 

The major risk factor for this condition is keratoconus, an eye disease characterized by outward bulging of the eye. 

People with this condition are poor candidates for laser refractive surgery.

Diffuse Lamellar Keratitis (DLK)

DLK is inflammation that occurs below the healing flap. Mild cases of DLK resolve with time. Severe DLK cases may require treatment with steroid eye drops. 

This condition is more common after IntraLase LASIK (iLASIK) surgery than with traditional bladed LASIK.

Irregular Astigmatism

Irregular astigmatism occurs when a person develops an uneven corneal surface. Although rare, it’s often associated with refractive eye surgery like LASIK.

Irregular astigmatism may result from a too-thin LASIK flap, uneven flap, or a faulty excimer laser. This complication requires immediate medical attention to correct. 

Flap Folds (Striae)

Thin and poorly repositioned flaps are common after LASIK. In most cases, they don’t cause severe issues. 

If the folds are large enough or lie on your visual axis, they can affect your vision. Your doctor can correct this problem by lifting, stretching, and repositioning it again if detected early.

Flap-folds that develop later may require more intense treatments like suturing, ironing, or phototherapeutic keratectomy (PTK).6

Flap Dislocation

Most cases of flap dislocation occur from: 

  • Eye rubbing or squeezing
  • Poor flap repositioning
  • Epithelial abrasions
  • Excessive dry eyes
  • Physical trauma

Your doctor will warn you about rubbing your eyes and provide lubricants to address dry eyes if they occur.


The risk of bacterial, fungal, and viral infections is high in open wounds. 

Although rare, exposure to dirty water, touching your eyes with dirty hands, and spending time in contaminated areas may lead to a corneal flap infection.

One notable eye infection after LASIK surgery is bacterial keratitis.7 This infection may result in pain, sensitivity to light, eye discharge, and decreased vision.

7 Tips for Preventing LASIK Flap Complications

Your surgeon will reduce your risk of complications by using sterilized equipment. 

They will also use professionalism and precision to ensure the best outcome. After the surgery, you’ll have the full responsibility of preventing complications.

Here are seven tips to help you through your post-LASIK recovery journey:

1. Follow Up with Your Doctor

Your doctor will monitor the healing process during follow-up visits. Even when you feel well, a routine checkup can help detect minor complications.

Plan your first follow-up visit within 24 to 48 hours after surgery.

Your surgeon will advise you on the proper follow-up schedule after LASIK. But those who experience complications are advised to make more follow-up visits.

2. Protect Your Eyes

Protective eye gear such as sunglasses can be helpful when healing after LASIK.

Wearing sunglasses not only protects your eyes from excess light but also dust and debris, which can harm the healing flap.

3. Avoid Intense Activity

Activities like contact sports and heavy lifting can harm the healing flap. Doctors recommend staying away from these activities for about a month as you heal.

Even if you can see clearly, avoid straining your eyes until your flap recovers fully.

When you resume strenuous activities, seek your doctor’s advice and protect your eyes to prevent accidental injuries.

4. Don’t Rub Your Eyes

Your eyes may feel itchy after LASIK surgery. But it’s important not to touch them. 

Rubbing your eyes may dislodge the healing corner flap. It can also introduce harmful bacteria to the wound.

Doctors recommend using artificial tears and lubricants to ease any discomfort. You can also wear eye goggles at night to prevent yourself from rubbing them while you sleep.

5. Avoid Makeup

Makeup such as mascara, eyeliners, and artificial eyelashes encourage bacteria growth, thus increasing the risk of flap infections.

Talk to your doctor about potential risks before wearing makeup after LASIK.

6. Avoid Getting Water Into Your Eyes

Water may be contaminated with bacteria and other infectious germs.8

As your corneal flap heals, any contact with contaminated water will result in infection.

Close your eyes in the shower and avoid swimming in rivers, lakes, oceans, or pools until your corneal flap heals.

7. Take Medications as Prescribed

After the surgery, you’ll use eye medication(s) to treat inflammation and prevent flap infections. 

To help with dryness, your doctor will likely prescribe painkillers, artificial tears, and other lubricating eye drops. Use these medications as prescribed.

If you need to take the medication(s) multiple times a day or every hour, do not skip a dose. Failure to follow directions might result in damage or a prolonged recovery time.

What to Do if Your LASIK Flap Moves or Dislodges

If your LASIK flap moves or dislodges, it’s considered a medical emergency. It can cause pain, watery eyes, and blurry vision.

Flap dislocation is rare and only occurs in 1 to 2% of LASIK patients.

In most cases, a flap dislodge results from mechanical trauma. This is likely to occur within 48 hours after surgery.9 

It’s a good idea to visit your surgeon to correct the complication if it occurs. Your surgeon will reposition and smooth the flap back into place.

Regular checkups allow your doctor to detect any healing flap issues early and treat them quickly.

Updated on  February 20, 2024
9 sources cited
Updated on  February 20, 2024
  1. Ide T. et al.,”Outcome of a 10-year follow-up of laser in situ laser keratomileusis for myopia and myopic astigmatism,” Taiwan Journal of Ophthalmology, Dec. 14
  2.  Bamashmus M. et al.,“Functional Outcome and Patient Satisfaction after Laser In Situ Keratomileusis for Correction of Myopia and Myopic Astigmatism,” National Center for Biotechnology Information (NCBI), Mar. 2015.
  3. Ortueta D. et al., “Microkeratome,” Science Direct, 2008
  4. Linna TU, Pérez-Santonja JJ. et al., “Recovery of corneal nerve morphology following laser in situ keratomileusis,” National Center for Biotechnology Information (NCBI)
  5. Salomão M et al,. “Dry eye associated with laser in situ keratomileusis: Mechanical microkeratome versus femtosecond laser,” National Center for Biotechnology Information (NCBI), Oct. 2009
  6. Reddy V. “Flap Striae After LASIK” American Academy of Ophthalmology, 31 Jul. 2020
  7. Basics of Bacterial Keratitis,” Centers for Disease Control and Prevention, 07 Apr. 2014.
  8. Bacteria and E. Coli in Water,” United States Geological Survey (USGS), 05 Jun. 2018
  9. Alvarez M.,  Montesel A., and Bataille L.,“Late traumatic flap dislocation seven years after femtosecond laser-assisted in situ keratomileusis,” International Journal of Opthamology. 18 May. 2019.
The information provided on VisionCenter.org should not be used in place of actual information provided by a doctor or a specialist.