MyopiaPhase 4NCT00350246
Long-term Effects of Laser Refractive Surgery
A Phase 4 study testing Laser Refractive Surgery in people with Myopia, run by Mayo Clinic at 1 site in United States.
Trial summary
This study will determine if there are short- and long-term postoperative differences in visual and corneal outcomes between different laser refractive surgical procedures. Read more about this study
- Who is it for?
- Ages 18 to 70 yearsHealthy volunteers can take part
- Conditions the study is for
- Myopia
- What is being tested?
- Laser Refractive Surgery
- Type of treatment
- Surgery or procedure
- How many people
- 62 participants
- Where
- 1 siteUnited States
- Study dates
- Jul 2004to Jan 2009
- Phase
- Phase 4
- 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 18 to 70 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Myopia 1-10 diopters No other ocular abnormalities except presbyopia
Trial locations and contacts
1 site in 1 country.
About this study
This study will determine if there are short- and long-term postoperative differences in visual and corneal outcomes between different laser refractive surgical procedures.
Read the detailed description
We will measure postoperative differences in visual acuity, contrast sensitivity, corneal light scatter, density of keratocytes and subbasal nerves, corneal sensitivity, corneal topography and wavefront between PRK performed with epithelial removal by a laser or by a rotary brush and between LASIK performed by using a microkeratome or by using a femtosecond laser. Measurements will be made at baseline and at intervals over 5 postoperative years in 21 LASIK patients, 20 PRK patients, and 20 unoperated controls.
- Conditions
- Myopia
- Being tested
- Laser Refractive Surgery
- Medical subject headings
- Myopia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Laser Refractive SurgeryProcedure or surgery
What is being measured
The primary outcome is the main question the study is designed to answer.
keratocyte density at 5 years
nerve density at 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jul 2006 (estimated)
- Study startJul 2004
- Primary completionJan 2009
- Study completionJan 2009
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for MyopiaStudies of the same condition, open and under way.
- More trials run by Mayo ClinicThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
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 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 62 participants (actual)
Sponsor and investigators
- Lead sponsor
- Mayo Clinic
- Sponsor type
- University, hospital or other
- Collaborators
- National Institutes of Health (NIH)
- Investigators
- William M. Bourne, M.D., Principal investigator, Mayo Clinic
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00350246
- Sponsor's protocol ID
- 66-04
- Status last verified
- Jan 2010
- First submitted
- 7 Jul 2006
- Last updated
- 28 Jan 2010
- Results posted
- No
Publications
Patel SV, McLaren JW, Kittleson KM, Bourne WM. Subbasal nerve density and corneal sensitivity after laser in situ keratomileusis: femtosecond laser vs mechanical microkeratome. Arch Ophthalmol. 2010 Nov;128(11):1413-9. doi: 10.1001/archophthalmol.2010.253.
PubMed 21060042Calvo R, McLaren JW, Hodge DO, Bourne WM, Patel SV. Corneal aberrations and visual acuity after laser in situ keratomileusis: femtosecond laser versus mechanical microkeratome. Am J Ophthalmol. 2010 May;149(5):785-93. doi: 10.1016/j.ajo.2009.12.023. Epub 2010 Mar 15.
PubMed 20227675
Study at a glance
From the registry record, last updated by the sponsor on 28 Jan 2010. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Long-term Effects of Laser Refractive Surgery
- ClinicalTrials.gov ID
- NCT00350246
- Acronym / sponsor ID
- 66-04
- Conditions
- Myopia
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 62 participants (actual)
- Lead sponsor
- Mayo ClinicUniversity, hospital or other
- Collaborators
- National Institutes of Health (NIH)
- Study start
- Jul 2004
- Primary completion
- Jan 2009 (actual)
- Study completion
- Jan 2009 (actual)
- First posted
- 10 Jul 2006 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will determine if there are short- and long-term postoperative differences in visual and corneal outcomes between different laser refractive surgical procedures.
Detailed description
We will measure postoperative differences in visual acuity, contrast sensitivity, corneal light scatter, density of keratocytes and subbasal nerves, corneal sensitivity, corneal topography and wavefront between PRK performed with epithelial removal by a laser or by a rotary brush and between LASIK performed by using a microkeratome or by using a femtosecond laser. Measurements will be made at baseline and at intervals over 5 postoperative years in 21 LASIK patients, 20 PRK patients, and 20 unoperated controls.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Laser Refractive Surgery | Procedure or surgery | – |
Primary outcome
keratocyte density at 5 years
nerve density at 5 years
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Jan 2010.
- Derived from this study: PubMed 21060042Patel SV, McLaren JW, Kittleson KM, Bourne WM. Subbasal nerve density and corneal sensitivity after laser in situ keratomileusis: femtosecond laser vs mechanical microkeratome. Arch Ophthalmol. 2010 Nov;128(11):1413-9. doi: 10.1001/archophthalmol.2010.253.
- Derived from this study: PubMed 20227675Calvo R, McLaren JW, Hodge DO, Bourne WM, Patel SV. Corneal aberrations and visual acuity after laser in situ keratomileusis: femtosecond laser versus mechanical microkeratome. Am J Ophthalmol. 2010 May;149(5):785-93. doi: 10.1016/j.ajo.2009.12.023. Epub 2010 Mar 15.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
William M. Bourne, M.D. principal investigator
Mayo Clinic
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Laser Refractive Surgery in people with Myopia, run by Mayo Clinic 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?
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 28 Jan 2010. 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.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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?
keratocyte density at 5 years. The study lists 2 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 NCT00350246, which also lists 2 linked publications.
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 28 Jan 2010.