A Prospective, Randomized Comparison of topography-guided LASIK surgery to wavefront-guided LASIK surgery

PURPOSE OF RESEARCH

You are invited to participate in a research study comparing the outcomes of wavefront­guided LASIK (laser in-situ keratomileusis) and topography-guided LASIK for nearsightedness. 

LASIK is a two-step procedure consisting of initial creation of a corneal flap ( a thin slice of the cornea) and subsequent corneal ablation (removal of tissue) with an excimer laser (a non-thermal laser). The cornea is the clear front portion_ of the eye. The femtosecond laser is used to create the corneal flap during the first step of the LASIK procedure. 

Wavefront aberrometry (a non-contact laser measuring device) is an automated device that measures the refractive status of the eye. This data is then transferred to the laser system and calculates a unique treatment to reduce or eliminate your nearsightedness with and without astigmatism (a non-spherical shape). 

Topography imaging (a non-contact measuring device) is an automated device that measures the shape of the cornea (the front cleared curved surface of the eye.) This data is then transferred to the laser system and calculates a unique treatment to reduce or eliminate your nearsightedness with and without astigmatism (a non-spherical shape). 

You will have one eye treated with topography-guided LASIK and your other eye treated with the wavefront-guided LASIK. 

You will be one of up to 50 near-sighted patients at Stanford to undergo treatment in this clinical research trial. 

This will be a prospective, randomized, research study in which up to 50 consecutive patients scheduled to undergo topography-guided LASIK in the first eye and wavefront­guided LASIK in the other eye for the correction of myopia (nearsightedness) will be emolled. 

The choice of which eye receives SMILE surgery and which eye receives the wavefront­guided LASIK will be randomized prior to enrollment. 

Randomization will be done according to a randomization schedule. You will know which eye is being treated with topography-guided LASIK and which eye will be treated with wavefront-guided LASIK. The randomization will determine only whether your right or left eye is treated with topography-guided LASIK. The other eye will be treated with wavefront-guided LASIK surgery. You have a fifty percent chance of having your left eye treated with topography-guided LASIK as your right eye. Participants will undergo bilateral (both eyes at once) surgery. 

All participants will be followed for one year after the vision correction procedure. 

Participants scheduled to undergo LASIK for the correction of myopia (nearsightedness) will be screened for eligibility. Eligible participants will be examined preoperatively to establish a baseline for ocular condition (the general health and glasses prescription of the eyes). Postoperatively, participants will undergo an ophthalmic evaluation ( complete eye examination) at regular intervals as specified in this protocol. Re­treatments (a second operation on the same eye for residual nearsightedness, farsightedness and/or astigmatism) will not be allowed during the first twelve months of this study. If you elect to undergo a retreatment of your LASIK surgery prior to the 12-month post-operative visit, the data after the retreatment procedure will be excluded from the study analysis. 

The primary aim of the research is to compare outcomes between the two procedures. All of the procedures performed during the study are considered standard of care for LASIK surgeries. 

If you should choose to participate, your eye will be given a thorough examination at each visit. This examination will include the standard elements of a general eye exam including testing of the eye's vision, contrast acuity testing, examination with the slit lamp and the ophthalmoscope to look at the various parts of the eye and a test of the inner eye's pressure. 

You will have at least one additional examination at 6 months for the study that you would not normally have if you had laser vision correction outside of the study. 

Your participation in this study is entirely voluntary. 

PROCEDURES

An excimer laser is a special type of laser system used to perform LASIK vision correction procedure. The excimer laser uses ultraviolet light to remove tissue from the cornea.

LASIK is a two-step procedure consisting of initial creation of a corneal flap and subsequent corneal ablation with an excimer laser. The cornea is the clear front portion of the eye. The femtosecond laser is used to create the corneal flap during the first step of the LASIK procedure.

The primary objective of this study is to compare topography-guided LASIK surgery to wavefront-guided LASIK surgery.

We will be using both subjective and objective outcome measures in our analysis.

This comparison will be made between both eyes of the same patient following LASIK surge1y. One eye will receive topography-guided LASIK surge1y and their fellow eye treated with wavefront-guided LASIK surgery. Both wavefront-guided LASIK and topography-guided LASIK surge1y have been found to be safe, predictable and effective when used for laser vision correction procedures. Both wavefront-guided LASIK surge1y and topography-guided LASIK surge1y used in this study have been approved for laser vision correction by the United States Food and Drug Administration. Standard refractive outcomes such as uncorrected visual acuity (vision without glasses or contact lenses) and best corrected visual acuity (vision with glasses or contact lenses), and intended vs. achieved postoperative refractions (the accuracy of the LASIK procedures) will be evaluated; in addition, higher order optical aberrations (micro-irregularities in the eye that can have subtle effects on the quality of vision) will be measured. 

INCLUSION AND EXCLUSION CRITERIA

Inclusion criteria: 

• Age 22 to 59 
• Nearsightedness between -1. 00 and -10. 00 diopters 
• Subjects with less than or equal to 3.00 diopters of astigmatism. 

Exclusion criteria: 

• Subjects with a history of previous ocular surgery 
• Subjects with excessively thin cornea 
• Subjects with topographic evidence of keratoconus 
• Subjects with ectatic eye disorders 
• Subjects with autoimmune diseases 
• Subjects who are pregnant or nursing 
• Subjects must have similar levels of nearsightedness in each eye. They can not be more than 1.5 diopters of difference between eyes 
• Subjects must have similar levels of astigmatism in each eye. They can not have more than 0.75 diopters of difference between eyes. 

FINANCIAL CONSIDERATIONS

Payment:

You will not be paid to participate in this research study. 

Costs: 

The customary fee for SMILE and LASIK surgery is $2,950.00 per eye. The procedure fee is being reduced by $1,475.00 to $1,475.00 per eye for participants participating in the research study. 

You will be responsible for a payment of $1,475.00 per eye. This covers the cost of the procedure and any re-operation for a period of two years. The $1,475.00 fee is rarely covered by your insurance. 

CONTACT INFORMATION

Appointment Contact:

Please contact Ms. Linda Schwa1tz at 650 498-7020 to obtain additional information about the study or to schedule an appointment for an evaluation.