Comparison of Outcomes Between TransPRK and Off-flap Epi-LASIK

Study Overview
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Brief Summary
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To compare the quantitative and qualitative optical outcomes between single-step transepithelial photorefractive keratectomy (TransPRK) and off-flap epipolis laser in situ keratomileusis (Epi-LASIK) in moderate to high myopia.we included patients with moderate to high myopia who were randomized to have TransPRK in one eye and Epi-LASIK in the other eye. All patients underwent comprehensive ophthalmological examinations, including uncorrected (UDVA) and corrected distance visual acuities (CDVA), manifest refraction, intraocular pressure, anterior and posterior segment examination, corneal topography measured by Scheimpflug scanning-slit topographer (Pentacam, Oculus Optikgerate GmbH), contrast sensitivity (CS) under photopic and mesopic conditions (CSV-1000E, Vector Vision Inc., Greenville, OH, USA) with correction by spectacles, ocular wavefront aberrometry (OPD-Scan II, Nidek Co. Ltd). At each follow-up, CS and aberration measures were repeated 3 times and the average value was analyzed. Optical parameters were repeated 1, 3, 6, and 12 months after surgery.Statistical analysis was performed using SPSS software (version 22.0, SPSS, Chicago, Inc.). Kolmogorov-Smirnov test was used to check the normal distribution of variables. Student t-test or Wilcoxon rank sum test was used based on the normality of data. A P value less than 0.05 was considered statistically significant.

Official Title
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Comparison of Outcomes Between Single-step Transepithelial Photorefractive Keratectomy and Off-flap Epipolis Laser in Situ Keratomileusis

Conditions
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Refractive Surgery

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age over 18 years corrected distance visual acuity (CDVA) in logarithm of minimal angle of resolution (LogMAR) of 0.10 or better refractive error stabilized for at least 1 year discontinued contact lens use for at least 2 weeks Exclusion Criteria: presence of corneal scars keratoconus glaucoma retinal diseases a history of corneal or intraocular surgery

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 38 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| aberrations | ocular high-order aberrations including spherical, coma and trefoil aberrations were measured by OPD-Scan II | 2016.03.01-2018.06.05 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| contrast sensitivity | contrast sensitivity and contrast sensitivity under glare condition measurements were performed by the CSV-1000E which could test four spatial frequencies: 3,6,12 and 18 cycles/degree (cpd) at 2.5m. The contrast sensitivity was measured under photopic (596.7cd/㎡) and scotopic (0.01cd/㎡) conditions and the contrast sensitivity under glare condition was taken under scotopic condition with glare | 2016.03.01-2018.06.05 | 
| haze | Corneal haze grade was recorded according to Fantes's report: 0, no haze; 0.5, trace haze only could be seen by oblique illumination; 1,more visible haze not interfering with the visibility of iris details; 2, mild influence of iris details; 3, moderate influence of iris details; 4, marked haze obscuring the stroma of ablation area. | 2016.03.01-2018.06.05 | 
| postoperative pain | Subjective pain scores were evaluated on the third day according to a predetermined scale ranging from 0 to 5 as follows: 0, no pain or discomfort; 1, photophobia and tears; 2, photophobia and tears with mild pain; 3, photophobia and tears with moderate pain that does not require oral medication; 4, photophobia and tears with severe pain that oral medication can relieve; 5, photophobia and tears with severe pain that oral medication cannot relieve. | 2016.03.01-2018.06.05 |