Rotational Stability of the Acrysof, Tecnis and Envista Intraocular Lenses

Brief Summary:

Age-related cataract is the main cause of impaired vision in the elderly population worldwide. In the UK, more than half of people who are over 65 years old have some cataract development in one or both eyes. The only treatment that can restore functional visual ability is cataract surgery where the opacified crystalline lens is removed by phacoemulsification and an artificial intraocular lens is implanted. It is estimated that around 10 million cataract operations are performed around the world each year. Cataract operations are generally very successful, with a low risk of serious complications.

During the past two decades, cataract surgery underwent tremendous change and modernisation resulting in today's small incision phacoemulsification surgery and a safe technique with a short rehabilitation time for the patient. Traditional spherical monofocal intraocular lenses (IOLs) restore best-corrected vision and may lessen the need for spectacles. These IOLs correct only the spherical portion of the total refractive error and do not correct corneal astigmatism. Astigmatism is a visually disabling refractive error affecting the general population, especially those with cataract. At least 15% to 20% of cataract patients have 1.5 diopters (D) or more of corneal or refractive astigmatism. With increased patient expectations, the trend is not only to remove the cataract but also to address the problem of pre-existing astigmatism at the time of surgery.

Surgical-induced astigmatism can be reduced by smaller incisions, i.e. microincision cataract surgery (MICS), which by definition is surgery performed through incisions smaller than 2.0 mm, reducing the need for suturing. This results in better corneal optical quality, thus improving visual outcomes. There are also other surgical options to correct preexisting astigmatism during cataract surgery like: selectively positioning of the phacoemulsification incision; astigmatic keratotomy with corneal or limbal relaxing incisions; excimer laser refractive procedures such as photorefractive keratectomy, laser in situ keratomileusis, and laser-assisted subepithelial keratectomy; or implanting pseudophakic toric posterior chamber intraocular lenses (IOLs).

Toric IOLs have been shown to result in good visual and refractive outcomes. Combined with MICS, these IOLs can allow effective correction of cylindrical errors intraoperatively, improving visual quality and thus leading to spectacle independence. Plate haptic and loop haptic toric IOLs have been considered for about a decade but have been associated with postoperative rotational instability. Rotation of a toric lens from its intended orientation degrades its corrective power, with approximately 3.3% loss of cylindrical power for every degree off axis. A misorientation of approximately 30° negates the effectiveness of astigmatic correction, and a misorientation of more than 30° may induce additional astigmatism. Although some patients are asymptomatic despite induced astigmatism, others experience symptoms such as blurred or distorted vision, headache, fatigue, eyestrain, squinting, or eye discomfort. Thus, IOL orientation stability is an essential goal in toric IOL design.

RATIONALE

The purpose of this study is to assess and compare the axial IOL rotation and optical quality (refraction, visual acuity, decentration and tilt) and capsular bag reaction after micro-incision surgery with an IOL implantation in cataract patients - Acrysof SN60WF, Tecnis ZCB00 & Envista MX60 IOL

Study Overview

• Status: Completed
• Conditions: Cataract; Astigmatism
• Intervention / Treatment: Other: Implantation of an Alcon Acrysof SN60WF intraocular lens; Other: Implantation of an AMO Tecnis ZCB00 intraocular lens; Other: Implantation of an Envista MX60 intraocular lens

• Study Type: Interventional
• Enrollment (Actual): 199
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Austria
  • Vienna, Austria, 1090
    • Medical University of Vienna Allgemeines Krankenhaus

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 90 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Uni- or bilateral age-related cataract necessitating phacoemulsification extraction and posterior IOL implantation
• Need for spherical IOL correction between 10.00 and 30.00 D
• Pupil dilation of ≥ 6.5 mm
• Age 40 and older

Exclusion Criteria:

• Corneal abnormality
• Pseudoexfoliation
• Preceding ocular surgery or trauma
• Uncontrolled glaucoma
• Proliferative diabetic retinopathy
• Iris neovascularization
• History of uveitis/iritis
• Microphthalmus
• Recurrent intraocular inflammation of unknown etiology
• Blind fellow eye
• Uncontrolled systemic or ocular disease
• Pregnancy and lactation

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Acrysof Rotation; Implantation of the Acrysof SN60WF Intraocular lens to the 0 ±10, 45± 10, 90±10 or 135± axis.	Other: Implantation of an Alcon Acrysof SN60WF intraocular lens; Patients suffering from senile cataract getting replaced their human crystalline cataractous lens
Active Comparator: Tecnis Rotation; Implantation of the Tecnis ZCB00 Intraocular lens to the 0 ±10, 45± 10, 90±10 or 135± axis.	Other: Implantation of an AMO Tecnis ZCB00 intraocular lens; Patients suffering from senile cataract getting replaced their human crystalline cataractous lens
Active Comparator: Envista Rotation; Implantation of the Envista MX60 Intraocular lens to the 0 ±10, 45± 10, 90±10 or 135± axis.	Other: Implantation of an Envista MX60 intraocular lens; Patients suffering from senile cataract getting replaced their human crystalline cataractous lens

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rotational stability from End of Surgery to 6 months	Change in axis position of an intraocular lens Alcon SN60WF, AMO Tecnis ZCB00 or Bausch&Lomb Envista MX60 from end of surgery (baseline axis) to 1 hour, 1 week, 1 month and 4-7 months (end of study visit). The change in axis position will be evaluated with respect to the baseline measurement at the end of surgery. Differences in axis position will be described as rotation in degrees (0 to 360°)	4-7 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Decentration	Decentration of the intraocular lens Alcon SN60WF, AMO Tecnis ZCB00 or Bausch&Lomb Envista MX60 will be measured with a Purkinje Meter. Decentration will be described as "Decentration in milimeter"	4 to 7 months
Tilt	Tilt of the intraocular lens Alcon SN60WF, AMO Tecnis ZCB00 or Bausch&Lomb Envista MX60 will be measured with a Purkionje Meter. Tilt will be described as "Tilt in degrees at a certain axis"	4 to 7 months

Collaborators and Investigators

• Sponsor: Medical University of Vienna

Study record dates

Study Major Dates

• Study Start (Actual): June 9, 2015
• Primary Completion (Actual): August 18, 2017
• Study Completion (Actual): August 18, 2017

Study Registration Dates

• First Submitted: April 8, 2020
• First Submitted That Met QC Criteria: April 10, 2020
• First Posted (Actual): April 14, 2020

Study Record Updates

• Last Update Posted (Actual): April 14, 2020
• Last Update Submitted That Met QC Criteria: April 10, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Refractive Errors; Cataract; Astigmatism
• Other Study ID Numbers: 1746/2014

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No