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Clinical Trials/NCT01097525
NCT01097525CompletedNot Applicable

Optical Quality, Threshold Target Identification, and Military Target Task Performance After Advanced Keratorefractive Surgery

Fort Belvoir Community Hospital2 sites in 1 country224 target enrollmentStarted: April 1, 2010Last updated:
Conditions
Interventions

Trial Snapshot

Phase
Not Applicable
Status
Completed
Enrollment
224
Locations
2
Primary Endpoint
objective image quality

Study Overview

Brief Summary

To determine the effect of two types of wavefront modalities (WFG vs. WFO) and two types of refractive surgery (PRK vs. LASIK) on visual and military task performance after laser refractive surgery.

Study Design

Study Type
Interventional
Allocation
Randomized
Intervention Model
Parallel
Primary Purpose
Treatment
Masking
None

Eligibility Criteria

Ages
21 Years to 55 Years (Adult)
Sex
All
Accepts Healthy Volunteers
Yes

Inclusion Criteria

  • •Normal, healthy active adults with access to medical care at Walter Reed Health Care System.
  • •Male or female at least 21 years old at the time of the pre-operative examination, and have signed an informed consent. The lower age limit of 21 years is intended to ensure documentation of refractive stability.
  • •Myopic spherical manifest refractive error from -1.00D up to -10.00D inclusive, with no more than 4.00D of manifest cylinder refractive error.
  • •Inclusion based on pre-op Central Corneal Thickness (CCT) will be assessed according to Residual Stromal Bed Thickness
  • •BSCVA of at least 20/20 in the study eye.
  • •Soft contact lens users must have removed their lenses at least two weeks prior to baseline and follow-up measurements.
  • •Hard contact lens users (PMMA or rigid gas permeable lenses) must have removed their lenses at least four weeks prior to baseline and follow-up measurements.
  • •Refractive stability must be documented by previous refractions. Spherical and cylindrical portion of the manifest refraction must not have varied by more than 0.50 diopters over the previous 12 months.
  • •Exhibits strong motivation for keeping the follow-up visits.
  • •Available for evaluation at Walter Reed during the 1 year follow-up period
  • •If selected, willing and available to undergo testing at Ft. Belvoir during the study period.
  • •All service members must have a signed command authorization to receive government sponsored refractive surgery. The signed command authorization will be included in the original application.
  • •Access to transportation to meet follow-up requirements.

Exclusion Criteria

  • •Residual, recurrent or active ocular diseases or congenital corneal abnormalities in either eye such as iritis, uveitis, keratoconjunctivitis sicca, herpetic keratitis, vernal conjunctivitis, lagophthalmos, corneal scarring, anterior basement membrane disease, recurrent erosions, glaucoma, previous steroid responder, occludable chamber angles, visually significant cataracts.
  • •History of any previous eye surgery or trauma, including previous refractive surgery.
  • •Dry eye as reflected by Schirmer's test, subjective complaints or symptoms of dry eye, findings during slit lamp exam that would be consistent with dry eye (e.g. superficial punctuate keratitis).
  • •Corneal thickness insufficient to allow the residual remaining stromal bed to be no less than 300 microns in each eye. The residual stromal bed thickness will be determined by subtracting both the LASIK flap thickness and depth of the ablation from the total central corneal thickness measured by pachymetry.
  • •Female subjects who are pregnant, breast-feeding or intend to become pregnant during the study. This is standard of care exclusion for refractive surgery at the Walter Reed Refractive Surgery Center because of the medications that are routinely given as part of the procedures. Standard of care analgesia consists of medications (e.g. narcotics) labeled as Pregnancy Category "C" by the FDA. Teratogenic effects are not known, however, physical dependence in the neonate may occur if the mother is given narcotics. Female subjects will be given a urine pregnancy test prior to participating in the study to rule out pregnancy.
  • •Concurrent topical or systemic medications that may impair healing, including corticosteroids, antimetabolites, isotretinoin (Accutane), amiodarone hydrochloride (Cordarone) and/or sumatripin (Imitrex).
  • •Significant corneal neovascularization.
  • •Progressive myopia or keratoconus.
  • •Medical condition(s), which, in the judgment of the investigator, may impair healing, including but not limited to: collagen vascular disease, autoimmune disease, immunodeficiency diseases, and ocular herpes zoster or simplex.
  • •Patients with known sensitivity or inappropriate responsiveness to any of the medications used in the post-operative course.
  • •Any physical or mental impairment which would preclude participation in any of the examinations.
  • •Inability to meet the mandated follow-up visit schedule for any reason such as duty hours, impending deployments, or PCS.

Arms & Interventions

Wavefront guided (WFG) PRK

Active Comparator

Intervention: WFG PRK (Procedure)

WFG LASIK

Active Comparator

Intervention: WFG LASIK (Procedure)

Wavefront optimized (WFO) PRK

Active Comparator

Intervention: WFO PRK (Procedure)

WFO LASIK

Active Comparator

Intervention: WFO LASIK (Procedure)

Outcomes

Primary Outcomes

objective image quality

Time Frame: 12 months postoperatively

as measured by wavefront aberrometry

visual outcomes

Time Frame: 12 months postoperatively

Visual outcomes will be measured in terms of: * number of eyes achieving uncorrected visual acuity (UDVA) 20/20 or better. * number of eyes maintaining one Snellen line of corrected distance visual acuity (CDVA). * number of eyes within 0.50 diopter of manifest spherical equivalent.

military task performance

Time Frame: 6 months postoperatively

as measured by threshold target identification and night firing range

visual performance

Time Frame: 12 months postoperatively

as measured by contrast sensitivity

Secondary Outcomes

No secondary outcomes reported

Investigators

Sponsor Class
Fed
Responsible Party
Principal Investigator
Principal Investigator

LTC Bruce Rivers

Director, Warfighter Refractive Eye Surgery Program and Research Center at FT Belvoir

Fort Belvoir Community Hospital

Study Sites (2)

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