Wavefront-guided Versus Wavefront-optimized LASIK for Nearsightedness

This is a research study comparing the outcomes of LASIK surgery for nearsightedness when
using the two different excimer laser technologies. Patients will have both eyes treated with
the Alcon WaveLight Allegretto excimer laser. You will be one of 150 sighted patients at
Stanford to undergo treatment in this clinical research trial. This will be a prospective,
randomized, research study in which up to 300 consecutive eyes scheduled to undergo excimer
laser in situ keratomileusis (LASIK) using one laser technology in the first eye and the
second laser technology in the fellow eye for the correction of myopia (nearsightedness) with
or without astigmatism will be enrolled. The choice of which eye receives the wavefront
guided technology and which eye receives the wavefront-optimized technology will be
randomized prior to enrollment. Randomization will be done according to a randomization
schedule. You will know which eye is being treated with which each technology. The
randomization will determine only whether your right or left eye is treated with the
wavefront guided technology. The other eye will be treated with wavefront-optimized laser
technology. You have a fifty percent chance of having your left eye treated with custom
wavefront guided technology as your right eye. Subjects will undergo bilateral (both eyes at
once) LASIK treatments using the Alcon WaveLight Allegretto excimer laser. All subjects will
be followed for one year after the vision correction procedure. Subjects scheduled to undergo
LASIK for the correction of myopia (nearsightedness) with or without astigmatism will be
screened for eligibility. Eligible subjects will be examined preoperatively to establish a
baseline for ocular condition (the general health and glasses prescription of the eyes).
Postoperatively, subjects 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) 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 retreated eye will be exited from the study as of the retreatment
date.

Any significant new finding developed during the course of the research which may relate to
the subject's willingness to continue participation will be provided to the subject or
subject's representative in a timely manner.

Inclusion Criteria:

- Subjects age 21 and older with healthy eyes.

- Nearsightedness between -7.50 diopters and -7.00 diopters with or without astigmatism
of up to 3.50 diopters.

Exclusion Criteria:

- Subjects under the age of 21.

- Patients with excessively thin corneas.

- Patients with topographic evidence of keratoconus.

- Patients with autoimmune diseases.

- Patients who are pregnant or nursing.

- Patients must have similar levels of nearsightedness in each eye. They can not be more
than 3.0 diopter of difference between eyes.

- Patients must have similar levels of astigmatism in each eye. They can not have more
than 4.0 diopters of difference in nearsightedness or astigmatism between their two
eyes.