Comparison of Toric IOL Implantation and Opposite Clear Corneal Incision During Cataract Surgery to Correct Corneal Astigmatism

Study Overview
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Brief Summary
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With increasing demands of patients concerning refractive outcome after cataract surgery, toric intraocular lenses (IOLs) that correct corneal astigmatism have been introduced more widely to cataract surgery. Originally toric IOLs were used mainly for patients with high degrees of astigmatism, especially after corneal surgical procedures such as penetrating keratoplasty. Since a couple of years, toric IOLs are available from numerous manufacturers to correct lower amounts of astigmatism which are much more prevalent with about 30% having a corneal astigmatism of 0.75D or more in the cataract population. This should result in less spectacle dependence of patients due to the astigmatic correction. The alternative method to reduce corneal astigmatism as part of cataract surgery is to make incisions on the steeper axis of the cornea such as limbal relaxing incisions or an additional clear corneal incision opposite (OCCI) to the main cataract opening. These techniques are in use since more than 2 decades and are widely used in clinical routine. As with toric IOLs, precise alignment of the cuts with the axis of astigmatism is essential. The disadvantage of the incisional techniques is the variability of the effect between patients since it depends on factors such as the extent of scaring of the cuts after surgery as well as corneal thickness. The main advantage is the simplicity of the technique and the lower cost. Aim of this study is to compare toric IOL implantation and opposite clear corneal incision during cataract surgery to correct corneal astigmatism.

Official Title
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Comparison of Toric IOL Implantation and Opposite Clear Corneal Incision During Cataract Surgery to Correct Corneal Astigmatism

Conditions
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Cataract, Corneal Astigmatism

Intervention / Treatment
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* Device: toric IOL
* Procedure: IOL combined with opposite clear corneal incision (OCCI)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cataract Age 21 and older Regular corneal astigmatism 1.0 up to 2.5 D written informed consent prior to surgery Exclusion Criteria: Relevant other ophthalmic diseases such as: pseudoexfoliation, glaucoma, traumatic cataract corneal scars, and other co-morbidity that could affect capsule bag stability ( e.g. Marfan syndrome) Irregular corneal astigmatism on corneal topography

Ages Eligible for Study
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Minimum Age: 21 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: toric IOL<br>aspherical, toric acrylic IOL (Lentis L-312T, Oculentis, Germany) | Device: toric IOL<br>* implantation of an aspheric, toric, acrylic IOL during cataract surgery<br>|
| Active Comparator: IOL combined with opposite clear corneal incision (OCCI)<br>aspherical, acrylic IOL with OCCI | Procedure: IOL combined with opposite clear corneal incision (OCCI)<br>* aspherical, acrylic IOL with opposite clear corneal incision during cataract surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative residual astigmatism |  | 9 months post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| uncorrected distance visual acuity (UDVA) |  | 9 months post-operatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cataract surgery, astigmatism, opposite clear corneal incision, toric IOL, IOL rotational stability