Wavefront-optimized LASIK is a procedure used to maintain or improve the shape of the cornea after primary refractive surgery with photorefractive keratectomy (PRK), laser-assisted subepithelial keratectomy (LASEK), or laser in situ keratomileusis (LASIK). It works by considering the cornea’s curvature and increasing the number of peripheral pulses. Wavefront-optimized LASIK is the most advanced of the LASIK procedures that results in fewer side effects.
Wavefront-optimized LASIK carries several advantages over conventional LASIK in that it minimizes an increase in higher order aberrations. LASIK is unable to address issues to do with higher order aberrations and sometimes is the cause of these higher order aberrations. Higher order aberrations refer to tiny optical defects that cause glare, haloes, and starbursts around light sources. These aberrations, unlike lower order aberrations in myopia, astigmatism, and hyperopia, cannot be corrected by glasses or contacts. Wavefront-optimized LASIK results in fewer complaints about night vision and produces better-quality vision. However, this technology does not address the problem of pre-existing higher order aberrations. The other advantage is that it is quicker and less expensive (avoids additional aberrometer expenses) than wavefront-guided technology.
Examples of approved wavefront-optimized LASIK lasers include the Wavelight EX500, said to be the most precise and quickest, Zeiss MEL-80, and Allegretto Wave Eye-Q.
Patients who undergo wavefront-optimized LASIK must have an ocular irregularity that affects the quality of vision. Individuals with or affected by the following should not undergo wavefront-optimized LASIK:
- Large pupils
- Lens opacity
- Corneal scarring
- Nursing of babies
- Ocular herpes simple
- Suspicious corneal topography
- Significant corneal neovascularization
- Conditions that compromise immune systems like autoimmune diseases
- Certain eye conditions like glaucoma, uncontrolled diabetes, diabetic retinopathy, or cataracts
Before the Procedure
A patient’s medical history will be taken. The patient should have had a stable refractive prescription for at least one year before the procedure. S/he will undergo an ophthalmic clinical exam that includes the following checks:
- Contact tonometry
- Ultrasound corneal pachymetry
- Comprehensive ophthalmic exam
- Cycloplegic and manifest refraction
- Corrected distance visual acuity (CDVA)
- Uncorrected distance visual acuity (UDVA)
The wavefront device measures aberrations in the shape and texture of the cornea. The refraction measurements are then programmed into the wavefront-optimized laser. The patients are also instructed to avoid wearing contact lenses for two weeks before the ophthalmic examination.
After the patient has been prepped, the surgeon will:
- Remove the epithelium using a rotating brush or a dilute solution
- Use an excimer laser to ablate the corneal stroma
- Apply a prophylactic, mitomycin C (MMC) on the stromal bed for about 15-60 seconds
- Apply a corneal shield that has been soaked in MMC for 20 seconds
- Irrigate the surface of the eye using a balanced salt solution
- Place a low oxygen-transmission bandage contact lens which will stay in place until complete re-epithelialization
Risks & Complications
Complications are rare in wavefront-optimized LASIK since it reduces incidences of glare, halo, and starbursts around light sources. However, some of the risks and complications associated with any laser surgery may include:
- Dry eyes
- Corneal haze
- Ocular hypertension
- Under correction or overcorrection
- Leaving the cornea too thin for future LASIK surgeries
- Inducing of significant higher order aberrations amounts
Aftercare & Recovery
The surgeon will prescribe a sterile topical ophthalmic solution four times a day for one week to prevent infection. S/he will also prescribe a topical anti-inflammatory ophthalmic solution to treat the inflammation that may result. It will be taken every two hours on the first three days following the procedure, then four times a day for the rest of the week followed by a six-week taper. For pain, the surgeon will prescribe a non-steroidal anti-inflammatory drug (NSAID) which the patient administers four times per day in the first 48 hours following surgery, and according to need. Preservative-free artificial tears are also prescribed to help with frequent lubrication of the eye.
The high-oxygen transmissible bandage contact lens used during surgery will be removed only when total re-epithelialization has occurred. The typical period when the bandage lens can be removed is between four to seven days.
The patient is evaluated a month after surgery with the ophthalmologist assessing the CDVA, UCVA, and refraction. Subsequent checks for the same follow at three and six months postoperatively. Other checks include visual acuity, contrast testing, and night vision testing.
Research indicates that wavefront-optimized LASIK preserved the cornea's natural shape after treatment in most of the patients. An increase in higher order aberrations was reduced. Consequently, nighttime glare, halo, and starbursts around light sources are reduced in these patients.