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MyopiaNCT01140594

Wavefront-guided Photorefractive Keratectomy (PRK) Versus Wavefront-guided Lasik for Myopia

A study testing Photorefractive keratectomy and Laser in-situ keratomileusis in people with Myopia and Astigmatism, run by Stanford University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

A prospective comparison of eyes undergoing wavefront-guided LASIK in one eye and wavefront-guided PRK in their fellow eye for myopia. Read more about this study

Who is it for?
Ages 21 years and olderHealthy volunteers can take part
Conditions the study is for
Myopia, Astigmatism
What is being tested?
Photorefractive keratectomy and Laser in-situ keratomileusis
Type of treatment
Surgery or procedure
Could I receive a placebo?
No, everyone receives an active treatment
How many people
34 participants
Where
1 siteUnited States
Study dates
Aug 2006to Jan 2008
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 21 years and older
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • Subjects age 21 and older with healthy eyes.
  • Nearsightedness between -0.75 diopters and -7.00 diopters with or without astigmatism of up to -3.50 diopters.

Who cannot join

  • Subjects under the age of 21.
  • Patients with thin corneas.
  • Patients with topographic irregularities.
  • Patients with 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 1.0 diopter of difference between eyes.
  • Patients must have similar levels of astigmatism in each eye. They can not have more than 1.0 diopter of difference between eyes.

Trial locations and contacts

1 site in 1 country.

United States1 site
  • Stanford University School of Medicine

    Stanford, California, 94305

Other trials in United States

About this study

Official title: A Prospective Randomized Eye to Eye Comparison of Fellow Eyes Undergoing Lasik With the IntraLase(TM) FS Versus PRK

A prospective comparison of eyes undergoing wavefront-guided LASIK in one eye and wavefront-guided PRK in their fellow eye for myopia.

Read the detailed description

This is a research study comparing the outcomes of LASIK surgery to PRK surgery for nearsightedness when using the two different procedures. You will have one eye treated with LASIK using the Intralase FS laser and your other eye treated with PRK. You will be one of 100 sighted patients at Stanford to undergo treatment in this clinical research trial. This will be a prospective, randomized, research study in which up to 200 consecutive eyes scheduled to undergo excimer laser in situ keratomileusis (LASIK) in one eye and photorefractive keratectomy (PRK) in the fellow eye for the correction of myopia (nearsightedness) with or without astigmatism will be enrolled. The choice of which eye receives LASIK and which eye receives PRK 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 procedure. The randomization will determine only whether your right or left eye is treated with the LASIK procedure. The other eye will be treated with PRK. You have a fifty percent chance of having your left eye treated with LASIK as your right eye. Subjects will undergo either bilateral (both eyes at once) wavefront (a more precise custom laser system) guided LASIK and PRK treatments using the VISX Star S4 excimer laser. All subjects will be followed for one year after the vision correction procedure. Subjects scheduled to undergo LASIK and PRK 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 six months of this study. If you elect to undergo a retreatment of your LASIK or PRK surgery prior to the 6-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.

Conditions
Myopia, Astigmatism
Being tested
Photorefractive keratectomy, Laser in-situ keratomileusis
Medical subject headings
Myopia, Astigmatism

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Photorefractive keratectomyProcedure or surgery

    Also called PRK, CustomVue, Wavefront-guided

    One eye undergoes wavefront-guided PRK with the Visx S4 CustomVue excimer laser.

  • Laser in-situ keratomileusisProcedure or surgery

    Also called LASIK, CustomVue, Visx, Intralase FS60

    One eye undergoes wavefront-guided LASIK using the Visx S4 excimer laser.

Study groups in NCT01140594
Study groupRoleWhat they receive
Wavefront-guided PRKActive comparatorWavefront-guided PRK
Receives: Procedure: Photorefractive keratectomy; Procedure: Laser in-situ keratomileusis
Wavefront-guided LASIKActive comparatorWavefront-guided LASIK
Receives: Procedure: Photorefractive keratectomy; Procedure: Laser in-situ keratomileusis

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Improvement in uncorrected visual acuity

    Measured: Baseline to one year

  2. Changes in best spectacle corrected visual acuity

    Measured: Baseline to one year

  3. Changes in 25 and 5% low contrast acuity

    Measured: baseline to one year

Secondary outcomes (3)
  1. Changes in quality of vision

    Measured: baseline to one year

  2. Comparison of dry eye signs and symptoms between LASIK and PRK

    Measured: baseline to one year

  3. Changes in higher order aberrations

    Measured: Baseline to one year

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted9 Jun 2010 (estimated)
  2. Study startAug 2006
  3. Primary completionJan 2008
  4. Study completionJan 2008

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Other
Allocation
Randomised
Intervention model
Parallel groups
Masking
None (open label)
Enrolment
34 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT01140594
Sponsor's protocol ID
SU-05192010-6082
Other IDs
SQL 97234
Status last verified
Apr 2022
First submitted
2 Jun 2010
Last updated
11 Apr 2022
Results posted
No
Data monitoring committee
No

Publications

  • Manche EE, Haw WW. Wavefront-guided laser in situ keratomileusis (Lasik) versus wavefront-guided photorefractive keratectomy (Prk): a prospective randomized eye-to-eye comparison (an American Ophthalmological Society thesis). Trans Am Ophthalmol Soc. 2011 Dec;109:201-20.

    PubMed 22253488

Questions about this trial

What is this clinical trial studying?

A study testing Photorefractive keratectomy and Laser in-situ keratomileusis in people with Myopia and Astigmatism, run by Stanford University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 11 Apr 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Improvement in uncorrected visual acuity (time frame: Baseline to one year). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT01140594, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Apr 2022.

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