Posterior Capsule Opacification and Frequency of Nd:YAG Treatment and of Two Microincision IOLs: Tecnis ZCB00 and Acrysof SA60AT

December 4, 2012 updated by: Rupert Menapace, Medical University of Vienna

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 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. The most common risk is developing a condition called posterior capsule opacification (PCO), which causes impaired vision to return.

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. The most frequent long-term complication of cataract surgery remains to be posterior capsule opacification (PCO). In the past few years, refinements in surgical technique and modifications in IOL design and material have led to a decrease in the incidence of PCO.

It has been shown that a sharp posterior optic edge inhibits migration of lens epithelial cells (LEC) behind the IOL optic and therefore have a lower incidence of posterior capsule opacification (PCO). Most IOL designs have open-loop haptics that are connected to the optic towards the end of the production process, also called multipiece designs.

For several reasons such as better ease of use with injector systems and higher efficiency in the production process, companies have developed IOLs with open-loop haptics out of one block of material, also called single-piece designs. In the case of such single-piece IOLs, the haptics tend to be much thicker than with multipiece IOLs. A potential drawback of the thick haptics maybe an incomplete closure of the capsule at the optic rim with a reduced bending effect of the posterior capsule around the posterior optic edge. Additionally, the posterior sharp edge is often discontinuous in the region of the haptic-optic junctions. These locations may serve as a scaffold for LECs to migrate behind the IOL optic resulting in PCO. Nowadays a multitude of different single piece IOLS are available, many of them similar but of course with some differences in regard to the chemical composition of the acrylic material and the IOL design.

The purpose of this study is to compare the intensity of posterior capsule opacification (PCO) between two different 1-piece foldable hydrophobic acrylic intraocular lenses (IOLs) with different design of the sharp posterior edge within a follow up period of three years.

Study Overview

Status

Completed

Study Type

Interventional

Enrollment (Actual)

54

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Vienna, Austria, 1090
        • Medical University Vienna

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

40 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Bilateral age-related cataract
  • Good overall physical constitution

Exclusion Criteria:

  • History of ocular disease or intraocular surgery
  • Laser treatment
  • Diabetes requiring medical control
  • Glaucoma
  • Severe retinal pathology that would make a postoperative visual acuity of 20/40 (decimal equivalent = 0.5) or better unlikely

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Other: Tecnis ZCB00
eyes with implantation of Tecnis ZCB00
Other: Acrysof SA60AT
eyes with implantation of Acrysof SA60AT

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Posterior capsule opacification (PCO)
Time Frame: 3 years
PCO = migration of lens epithelial cells behind the IOL optic after cataract surgery
3 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
frequency of neodymium:yttrium-aluminium-garnet (Nd:YAG) capsulotomy
Time Frame: 3 years
Treatment of PCO in neodymium:yttrium-aluminium-garnet (Nd:YAG) capsulotomy. The frequency of this treatment will be asseseed in absolute and relative (percentage) values
3 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

April 1, 2008

Primary Completion (Actual)

June 1, 2011

Study Completion (Actual)

October 1, 2012

Study Registration Dates

First Submitted

December 4, 2012

First Submitted That Met QC Criteria

December 4, 2012

First Posted (Estimate)

December 6, 2012

Study Record Updates

Last Update Posted (Estimate)

December 6, 2012

Last Update Submitted That Met QC Criteria

December 4, 2012

Last Verified

December 1, 2012

More Information

Terms related to this study

Other Study ID Numbers

  • EK128/2008

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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