Refractive Change Induced by 2.8-mm Corneal Incision

Study Overview
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Brief Summary
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The investigators' purpose is to study the induced refractive change caused by different 2.8-mm corneal incision locations in phacoemulsification, because the investigators hypothesize that the effect may be different for nasal, temporal, and superior location, although they are considered astigmatism neutral. Patients will be randomized to nasal or temporal incision, or assigned to superior incision, depending on preexisting astigmatism. Visual acuity, refraction, keratometry, Pentacam analysis, intraocular pressure, biomicroscopy, and funduscopy, will be carried out before and after phacoemulsification. Outcome measures will be induced corneal refractive change (Fourier power vector analysis), ISV change, and visual acuity, at 6 months.

Official Title
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Study of Refractive Change Induced by 2.8-mm Corneal Incisions for Cataract Surgery

Conditions
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Cataract, Refractive Surgery, Astigmatism

Intervention / Treatment
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* Procedure: Nasal 2.8-mm corneal incision
* Procedure: Temporal 2.8-mm corneal incision
* Procedure: Superior 2.8-mm incision


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Visual impairment for daily tasks caused by cataract Age older than 50 years Steep axis of corneal astigmatism at 90° ± 20° or 180° ± 20° Ability to cooperate in the protocol procedures Exclusion Criteria: Age below 50 Inability to cooperate with measurements

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 80 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: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: I<br>Nasal 2.8-mm corneal incision | Procedure: Nasal 2.8-mm corneal incision<br>* Phacoemulsification through a nasal 2.8-mm incision<br>* Other names: Phacoemulsification nasal incision;|
| Active Comparator: II<br>Temporal 2.8-mm corneal incision | Procedure: Temporal 2.8-mm corneal incision<br>* Phacoemulsification through a 2.8-mm temporal incision<br>* Other names: Phacoemulsification temporal incision;|
| Active Comparator: III<br>Superior 2.8-mm corneal incision | Procedure: Superior 2.8-mm incision<br>* Phacoemulsification through a superior 2.8-mm corneal incision<br>* Other names: Phacoemulsification superior incision;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Induced corneal refractive change |  | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ISV change |  | 6 months | 
| Visual acuity |  | 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Corneal incision, Cataract surgery, Phacoemulsification, Surgically induced astigmatism, Corneal Topography