Effect of Preoperative Pupil Size on Quality of Vision After Wavefront-Guided LASIK

Study Overview
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Brief Summary
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The purpose of this study is to evaluate whether the size of the pupil has an effect on quality of vision in patients undergoing LASIK surgery.

Detailed Description
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Purpose: To prospectively evaluate the effect of preoperative pupil size on quality of vision after wavefront-guided LASIK. Methods: Fifty-one patients underwent LASIK for low myopia and completed questionnaires regarding specific visual symptoms before and after surgery. Each eye was evaluated postoperatively at 1-week, 1-, 3-, 6- and 12-months. Pupils were stratified according to size: small (<5.5mm), medium (5.5 to 6.0mm) and large (>6.0mm). Mesopic pupil size and preoperative and postoperative variables were evaluated using analysis of variance (ANOVA). A regression model was also performed to determine the correlation between mean spherical equivalent and cylinder and visual symptoms.

Official Title
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Effect of Preoperative Pupil Size on Quality of Vision After Wavefront-Guided LASIK

Conditions
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Myopia

Intervention / Treatment
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* Procedure: LASIK


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: no more than 6.00 D of spherical myopia no more than 3.00 D of refractive astigmatism a stable refraction (less than 0.50D per year of sphere or cylinder) a corneal diameter of less than 11.0 mm to allow for suction ring fixation discontinuation of soft contact wear at least 7 days prior to preoperative evaluation visual acuity correctable to at least 20/20 age older than 21 years ability to participate in follow-up examinations for 12 months after LASIK surgery Exclusion Criteria: use of rigid gas permeable contact lens severe dry eye symptoms severe blepharitis anterior segment abnormalities (i.e. cataracts, corneal scarring, or neovascularization within 1 mm of intended ablation zone) recurrent corneal erosion severe basement membrane disease progressive or unstable myopia or keratoconus unstable corneal mires on central keratometry corneal thickness in which LASIK procedure would result in less than 250 microns of remaining posterior corneal thickness below the flap postoperatively baseline standard manifest refraction of more than 0.75 D in sphere power or a difference of greater than 0.50 D in cylinder power compared with baseline standard cycloplegic refraction a baseline standard cycloplegic refraction differing more than 0.75 in sphere, 0.50 D in cylinder have a different type of astigmatism (i.e. with-the-rule) when the cylinder is greater than 0.50D compared to baseline standard cycloplegic refraction preoperative assessment of ocular topography and/or aberrations indicates that either eye is not suitable candidate for LASIK vision correction procedure (i.e. forme fruste keratoconus corneal warpage, or pellucid marginal degeneration) previous intraocular or corneal surgery history of herpes zoster or simplex keratitis patients on systemic corticosteroid or immunosuppressive therapy immunocompromised subjects or clinically significant atopic disease connective tissue disease diabetes steroid responder macular pathology pregnant or lactating patients patients with sensitivity to planned study concomitant medications patients participating in another ophthalmic drug or device clinical trial
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: small<br> | Procedure: LASIK<br>* laser-assisted in situ keratomileusis<br>* Other names: laser-assisted in situ keratomileusis;|
| Active Comparator: medium<br> | Procedure: LASIK<br>* laser-assisted in situ keratomileusis<br>* Other names: laser-assisted in situ keratomileusis;|
| Active Comparator: large<br> | Procedure: LASIK<br>* laser-assisted in situ keratomileusis<br>* Other names: laser-assisted in situ keratomileusis;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |