Direct Comparison of TG and WFO LASIK

Study Overview
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Brief Summary
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To compare the efficacy to different profiles, direct head-to-head studies had been conducted. In one previous review study revealed that TG LASIK provided patient with better uncorrected visual acuity (UCVA) than WFO LASIK and WFG LASIK. In recent previous contralateral eye studies also showed that TG LASIK induced less postoperative higher-order aberration than WFO LASIK. However, these studies included only low-to-moderate myopia patients, for patients with high myopia (spherical equivalent > 6D), the effect of TG LASIK comparing with WFO LASIK had not been reported before. The aim of our study is to analyze and compare the visual performance of TG LASIK and WFO LASIK in high myopia and low-to-moderate myopia patients, , particularly UCVA, corrected distance visual acuity (CDVA), contrast sensitivity (CS), and wavefront aberration.

Official Title
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Contralateral Comparison of Togoguided LASIK and Wavefront-optimized LASIK

Conditions
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Keratomileusis, Laser In Situ, Contrast Sensitivity

Intervention / Treatment
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* Device: Topoguided LASIK
* Device: Wavefront optimized LASIK


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age between 20 and 50 years old CDVA of both eyes could reach 0.1 logarithm of the minimum angle of resolution (logMAR) stable refractive errors of myopia and astigmatism Exclusion Criteria: cataract corneal opacities or irregularities dry eye (Schirmer's test I ≤ 5mm) amblyopia coexisting ocular pathologies glaucoma non-dilating pupil history of intraocular surgery, laser therapy, or retinopathy optic nerve or macular diseases estimated postoperative cornea residual stromal thickness less than 250 μm pregnancy or under lactation uncontrolled diabetic mellitus or systemic immune disease refusal or unable to maintain follow-up

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 50 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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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Topoguided LASIK<br>Topoguided ablation profile on dominant eye | Device: Topoguided LASIK<br>* Topoguided ablation profile on dominant eye<br>|
| Active Comparator: Wavefront optimized LASIK<br>Wavefront optimized ablation profile on non-dominant eye | Device: Wavefront optimized LASIK<br>* Wavefront optimized ablation profile on non-dominant eye<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity | uncorrected visual acuity and corrected distance visual acuity | 3 months after surgery | 
| Corneal wavefront analysis | horizontal coma aberration (Z 3,1), spherical aberration (Z 4,0), and trefoil aberration | 3-months postoperative visit | 
| Contrast sensitivity | 4 spatial frequencies: 3, 6, 12, and 18 cycles per degree (cpd). | 3-months postoperative visit | 
| Quality of vision questionnaire | A 11-item questionnaire, item scores range from 0 to 10 and higher item scores in questionnaire indicated more difficulty in achieving specific visual tasks | 3-months postoperative visit |