Femto LASIK: Everything You Need to Know

Femtosecond LASIK, often called simply Femto LASIK, is a newer type of LASIK in which a blade is not used to cut the flap in the cornea. Instead, only lasers are used during the procedure.

How Femtosecond LASIK Works

The femtosecond (FS) laser is similar to Nd:YAG. It operates by creating photoionization of the cornea’s transparent tissue, or the epithelium. 

The FS laser and Nd:YAG laser work similarly, but the FS laser produces a pulse duration in the femtosecond range versus the ND:YAG laser, which produces a pulse duration in the nanosecond range. 

Because the pulse duration of the FS laser is significantly shorter than that of the Nd:YAG laser, the collateral damage is significantly less. This makes the FS laser safe for corneal procedures. The FS laser is also noted for its precision and dependability.

Looking for the Best LASIK Near You?

Find a LASIK Surgeon

Femtosecond Lasers: A Bladeless Technology

A femtosecond laser is a bladeless technology. In LASIK applications that use blades, the surgeon uses a microkeratome or oscillating blade that allows them to cut a hinged flap in the cornea.

By contrast, femtosecond lasers use a high-energy laser instead of a blade to create a corneal flap. 

Outside of that difference, both types of LASIK procedures — blade and bladeless — produce the same results.

When a Blade Is Used: Traditional LASIK 

Usually, a blade or microkeratome is used under the following circumstances:

• When a procedure is used for correcting a prior LASIK surgery
• When less suctioning is involved
• When the patient is diagnosed with glaucoma

Femtosecond or Bladeless Uses

When a patient undergoes LASIK without the blade, there are various benefits:

• There is a noticeably reduced risk of thickness variations or flap complications.
• After-surgery vision is usually better than when a blade is used.
• The surgery represents a safe and efficient approach for patients with serious refractive errors or thinner corneas.
• There is a reduction in postoperative side effects.
• The bladeless technology is gentle on the cornea.

Blade vs. Bladeless: Benefits & Drawbacks

Basically, if you have minor vision corrections, traditional LASIK offers a fast and convenient way to improve your eyesight. However, if you have more severe vision problems, the femtosecond laser may be a better choice, especially if you have a thin cornea.

One of the notable advantages of the bladeless femtosecond laser is control. Again, using this method substantially lowers the risk of flap complications, namely flap buttonholes, which are created when the surgeon makes an abnormal lamellar cut during a creation of the corneal flap. This can cause an irregularity in the corneal surface and loss of corrective visual acuity.

A blade may also lead to the creation of a partial flap or free cap, which happens when the hinge of a corneal flap detaches. If you have sensitive eyes or a unique refractive issue, the use of an FS or bladeless LASIK offers more precision.

According to research, eye dryness is less likely with Femto LASIK than with traditional LASIK. In one study, the use of an FS laser resulted in 9 percent of patients reporting dry eye following LASIK, whereas 46 percent of patients reported it with bladed LASIK.  

FS Laser Procedures

Currently, four types of femtosecond lasers are used for LASIK procedures, including Intralase, VisuMax, Femtec, and Ziemer. All produce precise corneal flaps and pose fewer risks for flap complications when compared to traditional LASIK with a microkeratome blade. 

Who Is Eligible for FS Laser LASIK Surgery?

People who benefit from the use of FS lasers are those undergoing cataract surgery, people who have more severe refractive errors, and individuals with thin corneas. Patients should be at least 18 years old, have good eye health, and have had a stabilized lens prescription for at least a year.

Can You Pay for FS LASIK Surgery With Insurance?

Any type of LASIK surgery is considered an elective procedure. So, insurance does not cover the cost. However, you can get discounts from insurance companies (around 15%), or opt for financing through a LASIK provider. You may also take advantage of HSA and FSA accounts for payment.

The out-of-pocket cost, per the national average, is $2,600 for each eye.

Paying for FS LASIK Using an HSA or FSA

A health savings account (HSA) uses untaxed dollars through a high-deductible health plan. Unused dollars roll over to the next tax year. You can also use a flexible savings account (FSA), opened through your employer. This account is funded with pretax dollars from your earnings. The plan usually follows a “use it or lose it” rule at year’s end.

What Happens During a Femto LASIK Procedure?

As noted, the bladeless technology uses a highly energized laser, rather than a blade, to make a corneal flap and reshape the cornea to improve the eyesight.

The FS laser is primarily used to correct refractive errors for people with thin corneas, though it is also used for corneal transplants. It is also sometimes recommended for cataract procedures.

Risks & Side Effects

As with any surgery, there are potential risks with Femto LASIK, similar to the risks associated with traditional LASIK.

When using the femtosecond laser for LASIK, it may take the surgeon longer to create the epithelial flap. However, advancements in technology are now addressing this problem.

Some patients develop transient light sensitivity syndrome, known as TLSS, which is treated with steroids and occurs weeks after undergoing an FS laser LASIK procedure. Micro-irregularities may also occur that lead to “rainbow glare,” or colored bands of light streaming from white sources of light. 

In some instances, gas bubbles may accumulate, which make it difficult for the surgeon to proceed with the process.

Diffuse lamellar keratitis may develop within the corneal flap. As the condition progresses, scarring on the cornea can occur. Patients with the condition display symptoms, such as foreign body sensation, pain, photophobia (eye sensitivity in bright light), and blurred vision.

Corneal ectasia is a rare complication that presents itself as the bulging and thinning of the cornea.

Despite these potential risks, Femto LASIK is largely viewed as a low-risk surgery with very high success rates.

Normal Reactions to the Surgery

After Femto LASIK surgery, you may experience the following during recovery:

• Sensitivity to light
• Watery eyes
• Mild pain
• Itching
• Burning
• Glare or halos around lights
• Bloodshot eyes

These symptoms are normal and usually disappear within a week’s time.

What to Expect During the Surgery

During the procedure, you will go through the following process:

• You’ll be placed in an adjustable reclining chair.
• Numbing eye drops are placed in the eyes.
• An eye speculum is used to keep you from blinking during the surgery.
• A suction ring is positioned on the pupil, so suction can be applied.
• A glass lens holds the eye’s globe steady and flattens the cornea.
• The surgeon applies the femtosecond laser, creating a surface flap.
• An excimer laser, using UV light, is applied for reshaping the cornea.
• The flap is replaced.
• Sutures are not needed for recovery.
• The surgery lasts about 30 minutes per eye.

Recovery

You’ll need to have someone drive you home after the procedure. Your eye doctor will give you instructions on the recovery process. 

It’s important to rest for a couple days and stay away from long sessions at the computer. You’ll also need to refrain from exercise or strenuous activities for a couple days.

Femto vs. PRK vs. SMILE

Femtosecond LASIK, PRK, and SMILE all offer ways to correct vision.

Femtosecond LASIK

Femtosecond LASIK creates a flap using a femtosecond laser. It is a bladeless technology, thereby reducing the depth of the cornea. 

The bladeless technology is proven to increase the precision of flap creation when compared to the use of the first-generation microkeratome blade.

PRK Refractive Surgery

Photorefractive keratectomy, or PRK surgery, removes surface cells on the epithelium (surface) of the cornea first before the surgeon uses a cool excimer laser to correct the vision and reshape the cornea.

PRK’s outcomes are identical to LASIK, with most people achieving 20/20 vision without the need for eyeglasses or contact lenses. The surgery is recommended for patients with irregularly shaped or thin corneas and those who suffer from chronic dry eye.

Instead of using an FS laser to create a flap, the surgeon usually applies an alcohol-based liquid for softening the cornea before using a brush to remove epithelial surface cells. The cornea is reshaped with a cool excimer laser.

The drawback of the surgery is that you’ll experience blurred vision during the healing process. Therefore, it’s best to have the surgery about two to four weeks apart for each eye. 

SMILE 

SMILE is an acronym that stands for small incision lenticule extraction. The surgeon uses a femtosecond laser to treat myopia (nearsightedness) and astigmatism or an abnormally shaped cornea.

The surgeon uses the laser to cut a disc-shaped piece of tissue within the cornea and make a slide cut to remove the disc. Lenticule refers to a disc. The removal of the lenticule is what alters the refraction.

In the U.S., optical surgeons use SMILE to treat -1 D to – 8D myopic patients who have no more than -0.50 D astigmatism and a refraction spherical equivalent of -8.25 D, stabilized for at least a year.

Is Femto LASIK Right for You?

The femtosecond laser represents a second-generation LASIK technology that makes surgical refractive error correction more precise. The use of the bladeless system for creating a flap makes it possible for people with thin or irregularly shaped corneas or severe refractive errors to experience better vision and fewer complications and risks.

Talk to your doctor about whether Femto LASIK may be right for you. Since it can result in a faster healing time and fewer potential complications, your eye surgeon may recommend Femto LASIK as the preferred choice for your situation.

References

1. Corneal Epithelium. Life Map Discovery.

2. Lasers (Surgery). (December 2022). American Academy of Ophthalmology.

3. Femtosecond Lasers and Laser Assisted in Situ Keratomileusis (LASIK). (November 2022). American Academy of Ophthalmology.

4. LASIK Flap Buttonhole Management. (January 2023). American Academy of Ophthalmology.

5. Femtosecond Laser in Laser in Situ Keratomileusis. (June 2010). Journal of Cataract & Refractive Surgery.

6. Chapter 14: Femtosecond-Laser-Assisted Cataract Surgery (FLACS). (August 2019). High Resolution Imaging in Microscopy and Ophthalmology: New Frontiers in Biomedical Optics.

7. Femtosecond-Laser Assisted Surgery of the Eye: Overview and Impact of the Low-Energy Concept. (February 2021). Micromachines.

8. How FLAK Is Changing Keratoplasty. (December 2011). Review of Ophthalmology.

9. Capsulorhexis Technique. (January 2022). American Academy of Ophthalmology.

10. Delayed-Onset Transient Light Sensitivity Syndrome after Corneal Collagen Cross-Linking: A Case Series. (Autumn 2019). Medical Hypothesis, Discovery & Innovation Ophthalmology Journal.

11. Diffuse Lamellar Keratitis. (November 2022). American Academy of Ophthalmologists.

12. What Is Small Incision Lenticule Extraction? (May 2022). American Academy of Ophthalmologists.

13. What’s Behind That SMILE. (February 2018). Review of Ophthalmology.