Femtosecond Laser-assisted Arcuate Incisions Versus Manual Arcuate Incisions Outcomes

Study Overview
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Brief Summary
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This study is designed to compare the effectiveness of LenSx laser arcuate relaxing incisions vs. manual (blade) arcuate relaxing incisions in patients with low, but significant, levels of astigmatism.

Detailed Description
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This study is a comparative, prospective, randomized contralateral eye study of visual outcomes after LenSx laser arcuate relaxing incisions utilizing the Woodcock nomogram at 90% thickness vs. manual (blade) fixed keratome diamond knife at 600 microns for arcuate relaxing incisions utilizing the Donnenfeld nomogram. Subjects will be assessed pre-operatively and at 1 day, 1 month and 3 months post-operatively. Clinical evaluations will include measurement of visual acuity, manifest refraction and corneal astigmatism measurement with the Lenstar and slit lamp exam.

Official Title
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Femtosecond Laser-assisted Arcuate Incisions Versus Manual Arcuate Incisions Outcomes

Conditions
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Cataract

Intervention / Treatment
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* Device: femtosecond laser system arcuate corneal incision
* Other: Manual LRI


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Subjects are eligible for the study if they meet the following criteria: Note: Ocular criteria must be met in both eyes. are willing and able to understand and sign an informed consent; are willing and able to attend all study visits; are more than 40 years of age, of either gender and any race; are presenting for cataract surgery or refractive lens exchange with a desire to reduce astigmatism and will be implanted with a non-toric lens have good ocular health, with no pathology that compromises visual acuity (outside of residual refractive error and cataract) have 0.50 D to 1.75 D of regular corneal astigmatism have potential acuity of 20/25 or better Are scheduled to have a non-toric monofocal intraocular lens (IOL) (SN60WF) lens implanted in both eyes Exclusion Criteria If any of the following exclusion criteria are applicable to the subject or either eye, the subject should not be enrolled in the study. Irregular astigmatism (e.g. keratoconus) Corneal pathology (e.g. scar, dystrophy, pterygium, moderate-to-severe dry eye) Monocular status (e.g. amblyopia) Previous radial keratotomy, corneal refractive surgery or other corneal surgery (e.g. corneal transplant, lamellar keratoplasty) Previous anterior or posterior chamber surgery (e.g., vitrectomy, laser iridotomy) Diabetic retinopathy Macular pathology (e.g. age-related macular degeneration, epiretinal membrane) History of retinal detachment Subjects who have an acute or chronic disease or illness that would confound the results of this investigation (e.g., immunocompromised, connective tissue disease, clinically significant atopic disease, diabetes, and any other such disease or illness), that are known to affect post-operative visual acuity. Pregnancy has a known effect on the stability of refractions and visual acuity. As such, subjects who become pregnant during the study will not be discontinued but their data may be excluded from analyses of effectiveness.

Ages Eligible for Study
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Minimum Age: 40 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
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Contralateral eye study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Femtosecond limbal relaxing incision (LRI)<br>Eyes will be treated with arcuate incisions from a femtosecond laser system. | Device: femtosecond laser system arcuate corneal incision<br>* Corneal arcuate incision made either with a blade (manual) or femtosecond laser system.<br>* Other names: LRI;|
| Active Comparator: Manual LRI<br>Eyes will be treated with arcuate incisions completed manually with a blade. | Other: Manual LRI<br>* Manual LRI<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Residual Refractive Astigmatism | Residual refractive astigmatism measured in diopters | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Eyes With Residual Refractive Astigmatism < 0.50 Diopters (D) | The number of eyes with residual refractive astigmatism < 0.50 diopters (D) | 3 months | 
| Uncorrected Monocular Distance Visual Acuity | Uncorrected monocular distance visual acuity in logMAR | 3 months | 
| Spherical Equivalent Refraction | Spherical equivalent refraction in diopters | 3 months | 
| Corneal Astigmatism | Anterior corneal astigmatism | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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astigmatism, limbal relaxing incisions