Comparison of the Visual Performance After Implantation of Multifocal Lens

Study Overview
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Brief Summary
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This is a prospective, consecutive, nonrandomized,comparative study. Comparison of the Visual Performance After Implantation of a Trifocal Intraocular Lens and Two Bifocal Intraocular Lenses

Detailed Description
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Multifocal intraocular lenses were introduced in the 1980s and have the benefit of promoting near and far vision simultaneous. However, these multifocal lenses have the disadvantages, including lower contrast sensitivity(CS) and visual discomfort, such as halos, glares and starburst, et al. Therefore, careful patient selection is crucial to achieve good postoperative results. The purpose of this study was to compare the visual outcomes and subjective visual quality between bifocal intraocular Lens(ReSTOR +2.5/+ 3.0D and Diff-aay) and trifocal intraocular Lens(AT Lisa tri 839MP). This prospective, nonrandomized, consecutive, comparative study included the assessment of 60 patients implanted with multifocal intraocular lens. visual acuity was tested in all cases. Ophthalmological evaluation included the measurement of uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected near visual acuity (UNVA), and uncorrected intermediate visual acuity (UIVA), the analysis of contrast sensitivity (CS), visual defocus curve, spectacle independence, patient satisfaction, residual sphere, spherical equivalent (SE), cylinder and complications.

Official Title
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Comparison of the Visual Performance After Implantation of a Trifocal Intraocular Lens(AT Lisa Tri 839MP) and Two Bifocal Intraocular Lenses(ReSTOR +2.5/+ 3.0D and Diff-aay)

Conditions
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Intraocular Lens

Intervention / Treatment
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* Procedure: trifocal lens
* Procedure: bifocal lens 1
* Procedure: bifocal lens 2
* Procedure: bifocal lens 3


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: cataract Exclusion Criteria: existence of any corneal disease; previous eye surgery; illiteracy; previous refractive surgery; expected postoperative corneal astigmatism more than 1.00D; higer-order aberration more than 0.3; spherical aberration more than 0.3μm; intraoperative or postoperative complications.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 90 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| trifocal lens<br>trifocal lens implantation(AT Lisa tri 839MP) | Procedure: bifocal lens 1<br>* phacoemusification +bifocal lens(Diff-aay) implantation<br>Procedure: bifocal lens 2<br>* phacoemusification +bifocal lens (ReSTOR +3.0D) implantation<br>Procedure: bifocal lens 3<br>* phacoemusification +bifocal lens (ReSTOR +2.5D) implantation<br>|
| bifocal lens 1<br>bifocal lens implantation(Diff-aay) | Procedure: trifocal lens<br>* phacoemusification + trifocal lens(AT Lisa tri 839MP) implantation<br>Procedure: bifocal lens 2<br>* phacoemusification +bifocal lens (ReSTOR +3.0D) implantation<br>Procedure: bifocal lens 3<br>* phacoemusification +bifocal lens (ReSTOR +2.5D) implantation<br>|
| bifocal lens 2<br>bifocal lens implantation(ReSTOR +3.0D) | Procedure: trifocal lens<br>* phacoemusification + trifocal lens(AT Lisa tri 839MP) implantation<br>Procedure: bifocal lens 1<br>* phacoemusification +bifocal lens(Diff-aay) implantation<br>Procedure: bifocal lens 3<br>* phacoemusification +bifocal lens (ReSTOR +2.5D) implantation<br>|
| bifocal lens 3<br>bifocal lens implantation(ReSTOR +2.5D) | Procedure: trifocal lens<br>* phacoemusification + trifocal lens(AT Lisa tri 839MP) implantation<br>Procedure: bifocal lens 1<br>* phacoemusification +bifocal lens(Diff-aay) implantation<br>Procedure: bifocal lens 2<br>* phacoemusification +bifocal lens (ReSTOR +3.0D) implantation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Uncorrected distance visual acuity | Uncorrected distance visual acuity (4m) were measured using the reading table model of the Early Treatment Diabetic Retinopathy Study charts (ETDRS; Vector Vision, Ltd, Greenville, OH, USA). | 3 months after surgery | 
| Uncorrected near visual acuity | Uncorrected near visual acuity (40cm) were measured using the reading table model of the Early Treatment Diabetic Retinopathy Study charts (ETDRS; Vector Vision, Ltd, Greenville, OH, USA). | 3 months after surgery | 
| Uncorrected intermediate visual acuity | Uncorrected intermediate visual acuity (60cm) were measured using the reading table model of the Early Treatment Diabetic Retinopathy Study charts (ETDRS; Vector Vision, Ltd, Greenville, OH, USA). | 3 months after surgery |