Efficacy of LASIK Versus PRK in Asians With Mild and Moderate Myopia - Full Text View

Purpose

Laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) are currently the 2 main refractive surgeries to correct myopia which are being performed worldwide, with more patients preferring LASIK to PRK because of better comfort and faster rehabilitation. However, in post-LASIK patients, there is a low risk of flap dislodgement. This risk increases with certain occupations which have a higher risk of trauma. Hence, there may be a role for PRK for people which such occupations, e.g. soldiers, parachutists, sportsman.

There are several non-randomised studies which show that PRK is as efficacious, predictable and safe as LASIK for low to moderate myopes. But there have been only a few randomized controlled studies to compare the efficacy and safety of the 2 treatment modalities and all studies comparing LASIK and PRK suffer from a high dropout rate during the follow-up period. We compared the efficacy, predictability, stability and safety of LASIK versus PRK over a one year duration with almost 100% attendance during all follow-up visits.

Condition	Intervention
Myopia	Procedure: Laser in Situ Keratomileusis (LASIK) Procedure: Photorefractive Keratectomy (PRK)

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Single Blind, Uncontrolled, Parallel Assignment, Safety/Efficacy Study

Official Title:	A Prospective, Randomized Trial Evaluating the Operational Efficacy of LASIK vs. PRK for the Correction of Low and Moderate Myopia in the Singapore Armed Forces

Further study details as provided by Singapore National Eye Centre:

Primary Outcome Measures:

Comparing the efficacy, predictability, stability and safety of LASIK versus PRK

Secondary Outcome Measures:

Comparing wavefront aberrometry of LASIK vs PRK
Comparing patient satisfaction of LASIK vs PRK
Comparing effects of LASIK vs PRK in terms of post-surgery performance in the military setting

Study Start Date:	November 2002
Estimated Study Completion Date:	August 2005

Detailed Description:

This study is a prospective, randomized, clinical trial comparing the efficacy, predictability, stability and safety of LASIK versus PRK in a volunteer group of myopic military servicemen recruited from the Singapore Armed Forces. 132 subjects who were eligible for the study were randomized to undergo either LASIK or PRK in both eyes in a 2:1 ratio. 45 subjects (90 eyes) underwent PRK and 87 subjects (174 eyes) underwent LASIK.

An additional 59 subject underwent a non-randomised arm of the study and underwent PRK.

Eligibility

Ages Eligible for Study:	21 Years to 40 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Male and female subjects were eligible for the study if they were 18 years old or older and had given informed consent; had stable myopia ranging from -2.00 to -5.00D of spherical equivalent myopia, but less than 2.00D of refractive astigmatism as determined by manifest refraction for at least 6 months; a best corrected visual acuity of at least 20/20 and a stable keratometry after not wearing soft contact lenses for at least 2 weeks and hard lenses for at least 3 weeks. Study subjects were required to have a minimum cornea thickness of at least 460um as measured by Orbscan pachymetry.

Exclusion Criteria:

Subjects were excluded if they had corneal or anterior segment pathology, or myopic peripheral retinal degeneration or myopic macular degeneration; clinical signs of progressive or unstable myopia or keratoconus or were keratoconus suspects; were one-eyed patients; had undergone previous ocular surgery; had a history of herpes zoster ophthalmicus or herpes simplex keratitis; had a history of steroid-responsive rise in intraocular pressure or had a preoperative intraocular pressure of more than 21 mmHg in either eye; had diabetes mellitus, auto-immune disease, severe dry eye, connective tissue disease or significant atopy; on chronic systemic corticosteroid or immunosuppressive therapy; had a cornea thickness which would have resulted in less than 250 microns of remaining posterior corneal thickness below the flap postoperatively or had a central corneal endothelial cell count of less than 1500 cells/mm2 in either eye

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00348049

Locations


Singapore
	Singapore Eye Research Institute
	Singapore, Singapore, 168751

Sponsors and Collaborators

Singapore National Eye Centre

Singapore Armed Forces

Defence Medical Environmental Research Institute

Investigators


Principal Investigator:	Donald Tan, FAMS	Singapore Eye Research Institute

Principal Investigator:	Benjamin Seet	Singapore Armed Forces

More Information

Study ID Numbers:	R277/21/2002
First Received:	June 30, 2006
Last Updated:	October 23, 2006
ClinicalTrials.gov Identifier:	NCT00348049
Health Authority:	Singapore: Domain Specific Review Boards

Keywords provided by Singapore National Eye Centre:

LASIK

PRK

Myopia

Study placed in the following topic categories:

Eye Diseases

Myopia

Refractive Errors

ClinicalTrials.gov processed this record on October 10, 2008

Sponsors and Collaborators:	Singapore National Eye Centre Singapore Armed Forces Defence Medical Environmental Research Institute
Information provided by:	Singapore National Eye Centre
ClinicalTrials.gov Identifier:	NCT00348049