Topography-guided LASIK Surgery

Study Overview
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Brief Summary
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The investigators are analyzing outcomes of topography-guided LASIK surgery in participants with myopia and myopic astigmatism

Detailed Description
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The investigators are analyzing outcomes of topography-guided LASIK surgery in participants with myopia and myopic astigmatism. The investigators will be monitoring changes in anterior segment optical coherence tomography epithelial thickness maps. The investigators will compare preoperative maps to postoperative maps at one, three, six and twelve months. In addition, the investigators will measure changes in epithelial maps from postoperative month through twelve months to help understand what is happening to the corneal epithelium to try to explain why UDVA and CDVA improves over time

Official Title
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A Prospective Evaluation of Topography-guided LASIK Surgery

Conditions
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Myopia

Intervention / Treatment
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* Procedure: Topography-guided LASIK


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects age 18 and older with healthy eyes. Nearsightedness between -0.50 diopters and -8.00 diopters. Subjects with up to 3.00 diopters of astigmatism. Subjects with a spherical equivalent of up to -9.00 diopters. Exclusion Criteria: Subjects under the age of 18. Subjects with excessively thin corneas. Subjects with topographic evidence of keratoconus. Subjects with ectatic eye disorders. Subjects with autoimmune diseases. Subjects who are pregnant or nursing. Subjects with more than 3.00 diopters of astigmatism

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 59 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Interventional Model Description: Topography guided
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Topography guided LASI<br> | Procedure: Topography-guided LASIK<br>* LASIK surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Epithelial thickness maps | Changes in anterior segment optical coherence tomography epithelial thickness maps. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in corrected visual acuity | Corrected distance visual acuity (CDVA) | 12 months | 
| Uncorrected distance visual acuity | Uncorrected distance visual acuity (UDVA) | 12 months | 
| Quality of Vision | Patient reported outcomes questionnaire | 12 months | 
| Predictability | Percentage of eyes within +/-0.25, 0.50 and 1.00 diopter of the intended correction | 12 months | 
| Contrast visual acuity | 5 and 25% ETDRS contrast acuity | 12 months | 
| Residual astigmatism levels after surgery | Vector analysis of astigmatic outcomes | 12 months | 
| Change in refraction over time | Change in spherical equivalent over time | 12 months |