Initial Evaluation of Photorefractive Keratectomy in U.S. Army Personnel

Myopia Clinical Trial

Official title:

Initial Evaluation of Photorefractive Keratectomy in U.S. Army Personnel

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00413673
• Other study ID #: WRAMC WU # 2335-99
• Status: Completed
• Phase: N/A
• First received: December 19, 2006
• Last updated: March 31, 2008
• Start date: August 2001
• Est. completion date: March 2008

Study information

• Verified date: November 2007
• Source: Walter Reed Army Medical Center
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Federal Government
• Study type: Interventional

Clinical Trial Summary

The objective of this study is to conduct a prospective clinical trial to evaluate the safety and efficacy fo the VISX Excimer Laser system for the treatment of naturally occurring low to moderate myopia, with or without low levels of astigmatism, in U.S. Army personnel.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 100
• Est. completion date: March 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 21 Years and older

Eligibility

Inclusion Criteria:

• Informed consent.

• Normal, healthy active adults with access to medical care at Walter Reed Health Care System.

• Age 21 years or older.

• Spherical equivalent of the manifest refractive error between -1.0 to -6.0 diopters (D), inclusive, with no more than 3.0D of cylinder. The absolute value of the cylinder (expressed in minus cylinder) will be limited such that the short axis of the elliptical ablation will be no smaller than 4.9mm. The following specifies the maximum cylinder for a given spherical component of the manifest refraction:

Spherical component / Maximum cylinder

• 1.0D / -0.5D

• 2.0D / -1.0D

• 3.0D / -1.5D

• 4.0D / -2.0D

• 5.0D / -2.5D

• 6.0D / -3.0D

• Corrected vision of at least 20/20

• Soft contact lens users must havE removed their lenses at least two weeks prior to baseline measurements.

• Hard contact lens users (PMMA or rigid gas permeable lenses) must have removed their lenses at least four weeks prior to baseline measurements. At least two weekly manifest refractions and keratometry measurements will be required in this interval. The last two measurements must not vary by more than 0.50D in any meridian.

• Patients undergoing orthokeratology must have their lenses removed at least 6 months prior to the baseline examination. At least two monthly manifest refractions and keratometry measurements taken after the third month out of lenses must not vary by more than 0.50D in any meridian.

• Refractive stability must be documented by previous refractions. Spherical and cylindrical portion of the manifest refraction must not have varied by more than 0.50D over the previous 12 months.

• Exhibits strong motivation for keeping the follow-up visits.

• Available for evaluation at Walter Reed during the two-year follow-up period.

• Service members must have their command approval to participate in the study.

• Access to transportation to meet follow-up requirements.

Exclusion Criteria:

• Residual, recurrent or active ocular diseases or corneal abnormalities in either eye such as iritis, uveitis, keratoconjunctivitis sicca, herpetic keratitis, vernal conjunctivitis, lagophthalmos, corneal scarring, glaucoma, previous steroid responder, occludable chamber angles, visually significant cataracts.

• Either one or both eyes suffering from chronic dryness.

• Taking any systemic medications that may affect wound healing such as corticosteroids or antimetabolites.

• Patient corneal neovascularization within one mm of the ablation zone.

• History of any previous eye surgery, including previous refractive surgery.

• Best corrected visual acuity of less than 20/20.

• Progressive myopia or keratoconus.

• Any systemic disease that may affect wound healing, such as connective tissue disorders (rheumatoid arthritis, systemic lupus erythematosus, etc.), diabetes, or severe atopic disease.

• Any physical or mental impairment that would preclude participation in any of the examinations.

• For contact lens users there must be no evidence of contact lens corneal warpage on computerized topography.

• Currently on flight status or projected to be on flight status within ten years.

• Pregnant or breast-feeding an infant. Women of childbearing age must take a urine blood pregnancy test before starting this study

Study Design

Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Myopia

Intervention

Procedure:
• PRK
PRK

Locations

Country	Name	City	State
United States	Walter Reed Army Medical Center, Center For Refractive Surgery	Washington	District of Columbia

Sponsors (1)

Lead Sponsor	Collaborator
Walter Reed Army Medical Center

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	safety and efficacy of PRK		12 months after surgery