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Long-term Effects of Laser Refractive Surgery

This study has been completed.
National Institutes of Health (NIH)
Information provided by:
Mayo Clinic Identifier:
First received: July 7, 2006
Last updated: January 27, 2010
Last verified: January 2010
This study will determine if there are short- and long-term postoperative differences in visual and corneal outcomes between different laser refractive surgical procedures.

Condition Intervention Phase
Myopia Procedure: Laser Refractive Surgery Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Long-term Effects of Laser Refractive Surgery

Further study details as provided by Mayo Clinic:

Primary Outcome Measures:
  • keratocyte density at 5 years
  • nerve density at 5 years

Enrollment: 62
Study Start Date: July 2004
Study Completion Date: January 2009
Primary Completion Date: January 2009 (Final data collection date for primary outcome measure)
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.

Ages Eligible for Study:   18 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Myopia 1-10 diopters No other ocular abnormalities except presbyopia
  Contacts and Locations
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Please refer to this study by its identifier: NCT00350246

United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States, 55905
Sponsors and Collaborators
Mayo Clinic
National Institutes of Health (NIH)
Principal Investigator: William M. Bourne, M.D. Mayo Clinic