Hydrophobic Acrylic Toric IOL Designed to Reduce the Effects of Preoperative Corneal Astigmatism

Study Overview
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Brief Summary
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The investigational enVista IOL, Model MX60Tis equipped with toric optics and axis marks on the posterior surface to minimize the possibility of surgically induced astigmatism.

Detailed Description
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The investigational enVista Toric IOL, Model MX60T, and the currently approved Model MX60, are identical with the exception of the addition of toric optics and axis marks on the posterior optic surface for the correction of astigmatism on the Model MX60T. Both lenses have an aspheric biconvex optic with a modified C haptic monoblock, single-piece design. The design and material of both the MX60 and MX60T allow them to be folded and inserted through small incisions to minimize the possibility of surgically induced astigmatism (SIA).

Official Title
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To Evaluate the Safety and Effectiveness of the EnVista® One-Piece Hydrophobic Acrylic Toric IOL Designed to Reduce the Effects of Preoperative Corneal Astigmatism on Postoperative Refraction Following Cataract Surgery

Conditions
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Astigmatism

Intervention / Treatment
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* Device: enVista® One-Piece Hydrophobic Acrylic Toric IOL
* Device: enVista control lens


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subjects must have a clinically significant cataract in the study eye that is considered amenable to treatment with standard phacoemulsification cataract extraction. Subjects must require a lens power from 16.0 D to 27.0 D in the study eye. Subjects must be willing to discontinue contact lens wear for the duration of the study and, demonstrate stability prior to biometry and surgery in the study eye. Subjects must have a best corrected distance visual acuity (BCDVA) projected to be better than 20/30 after toric IOL implantation in the study eye. Subjects must have predicted postoperative corneal astigmatism between 0.90D and 2.40D in the study eye, as determined by the Toric Calculator. Subjects must have a minimum preoperative corneal astigmatism of 0.90 D in the study eye. Subjects must have a dilated preoperative pupil size greater than or equal to 5.0 mm in the study eye. Exclusion Criteria: Subjects who have had previous intraocular or corneal surgery in the study eye. Subjects with any clinically significant ocular pathology which would be expected to reduce potential BCDVA to 20/30 or worse in the study eye during the course of the study. Subjects with any anterior segment pathology in the study eye likely to increase the risk of complications from phacoemulsification cataract surgery. Subjects with associated ocular conditions which could affect the stability of the IOL in the study eye. Subjects with a traumatic cataract in the study eye. Subjects with uncontrolled glaucoma in the study eye. Subjects with clinically significant irregular corneal astigmatism in the study eye, as determined by the medical judgment of the Investigator. Subjects with clinically significant corneal pathology potentially affecting topography of either eye. Subjects with any ocular condition that could prevent the possibility of a visual outcome better than 20/30 in the study eye. Subjects with a difference of greater than 0.50D of corneal astigmatism as measured with the IOL Master and the topographer in the study eye using vector analysis. Subjects with an anterior chamber depth <2mm in the study eye. Subjects with potential BCDVA of 20/200 or worse in the fellow eye.

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
Interventional Model Description: A Prospective, Multicenter Clinical Trial to Evaluate the Safety and Effectiveness
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: enVista® One-Piece Hydrophobic Acrylic Toric IOL<br>Toric cylinder power of either 1.25 diopters (D), 2.00 D, or 2.75 D | Device: enVista® One-Piece Hydrophobic Acrylic Toric IOL<br>* Test lens having a toric cylinder power of either 1.25 diopters (D), 2.00 D, or 2.75 D<br>|
| Experimental: enVista control lens<br>Spherical control lens | Device: enVista control lens<br>* Spherical Control lens<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Dioptric Change in Cylinder | Dioptric change in cylinder from the preoperative keratometric cylinder magnitude to postoperative manifest refraction cylinder magnitude (referenced to the corneal plane). | Baseline, Final Visit (scheduled within window: days 120-180) | 
| Percentage of Participants With Intraocular Lens (IOL) Rotation of Less Than or Equal to Five Degrees | Intraocular Lens (IOL) rotation of less than or equal to five degrees between Forms 3 (scheduled within window: days 30-60) and final visit (scheduled within window: days 120-180). | Form 3 Visit (window: days 30-60), Final Visit (window: days 120-180) | 
| Mean Best-corrected Distance Visual Acuity (BCDVA) at Final Visit | Best-corrected distance visual acuity (BCDVA) at Final Visit, expressed as logarithm of the minimum angle of resolution (logMAR). Corrected means spectacle corrected. Visual acuity (VA) was reported as letters read correctly, and the letters read were converted to logarithm of the minimum angle of resolution (logMAR) acuity. The participant read rows of letters on a standard LogMAR chart until the participant misses 3 letters on a row with 5 letters. The total number of correct letters were recorded. A decrease in the number of correct letters indicates a decrease in visual acuity. | Final Visit (scheduled within window: days 120-180) | 
| Percentage of Participants With Reduction in Cylinder Within 0.50 Diopter (D) and Within 1.00 D of Intended. |  | Final Visit (scheduled within window: days 120-180) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Uncorrected Distance Visual Acuity (UCDVA) at Final Visit | Uncorrected distance visual acuity (UCDVA), expressed as logarithm of the minimum angle of resolution (logMAR). Uncorrected means not spectacle-corrected. Visual acuity (VA) was reported as letters read correctly, and the letters read were converted to logarithm of the minimum angle of resolution (logMAR) acuity. The participant read rows of letters on a standard LogMAR chart until the participant misses 3 letters on a row with 5 letters. The total number of correct letters were recorded. A decrease in the number of correct letters indicates a decrease in visual acuity. | Final Visit (scheduled within window: days 120-180) |