Changes of Angle Kappa After Implantation of Multifocal Intraocular Lenses

Study Overview
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Brief Summary
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The purpose of this study is to evaluate possible changes of angle kappa after multifocal intraocular lens implantation. Presumable influencing factors of postoperative visual axis shift (ie. biometric parameters of the eye) are investigated to determine the degree and direction of angle kappa alterations.

Detailed Description
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The purpose of this study is to evaluate changes of angle kappa after multifocal intraocular lens implantation. During cataract surgery Medicontur Bi-Flex 677MY IOL and Alcon Acrysof Restor SN6AD1 IOL are implanted. Optical biometry is carried out for IOL calculation and to measure axial length and angle kappa. Three months after surgery biometry is repeated, IOL position and angle kappa are measured using Scheimpflug-camera.

Official Title
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Changes of Angle Kappa After Implantation of Multifocal Intraocular Lenses

Conditions
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Presbyopia, Cataract

Intervention / Treatment
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* Procedure: cataract surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with age related cataract and presbyopia Exclusion Criteria: Patients with previous ocular surgery, trauma, active ocular disease, poorly dilated pupils, or known zonular weakness and corneal astigmatism >1.5 diopters were excluded from the study.

Ages Eligible for Study
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Minimum Age: 18 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: Bi-Flex<br>Medicontur Bi-Flex 677MY IOL was implanted into 24 eyes of 12 patients during cataract surgery. Angle kappa, biometric data and IOL decantation were measured. | Procedure: cataract surgery<br>* cataract surgery with phacoemulsification and implantation of multifocal posterior chamber intraocular lens<br>|
| Active Comparator: ReStor<br>and Alcon Acrysof Restor SN6AD1 IOL was implanted into 36 eyes of 18 patients during cataract surgery. Angle kappa, biometric data and IOL decantation were measured. | Procedure: cataract surgery<br>* cataract surgery with phacoemulsification and implantation of multifocal posterior chamber intraocular lens<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Measurement of changes of angle kappa after multifocal intraocular lens implantation. | Changes in magnitude and orientation of angle kappa (deviation between the visual and pupillary axis) are measured before and after cataract surgery with multifoocal intraocular lens implantation. During pre-and postoperative examination optical biometry is carried out using Lenstar LS 900. Optical biometer determines deviation between the visual and pupillary axis that represents angle kappa. Deviation of these axes can be defined by its magnitude and orientation. Location of the pupil centre relative to the visual axis - the reference axis - is determined by x- and y-offsets using trigonometrical analysis. | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determination of influencing effect of biometrical data on postoperative visual axis shift | Biometry data (axial length, keratometry, lens thickness, anterior chamber depth) are measured preoperatively by Lenstar LS 900 optical biometer. Their effect on changes of angle kappa is determined using statistical analysis. | 3 months | 
| Determination of influencing effect of intraocular lens decentration on postoperative visual axis shift | Three months after cataract surgery postoperative intraocular lens (IOL) position is determined using a rotating Scheimpflug-camera (Galilei G4). IOL decentration is obtained from the distance between the IOL centre and visual axis. The effect of possible IOL decentration on changes of angle kappa is determined using statistical analysis. | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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multifocal intraocular lens, angle kappa, presbyopia