Visual Field Changes in TECNIS ZCB00 Monofocal vs. TECNIS Symfony Extended Depth of Focus Intraocular Lens Implantation

October 1, 2019 updated by: Tony Lin, Western University, Canada

Visual Field Changes in Patients Undergoing TECNIS ZCB00 Monofocal vs. TECNIS Symfony Extended Depth of Focus Intraocular Lens Implantation

Glaucoma is a leading cause of blindness worldwide. Damage to the optic nerve results in vision loss gradually. This vision loss can be detected by using visual field testing, and is a way of monitoring glaucoma progression. As this population ages, cataracts develop, and patients need to undergo cataract surgery to replace the cloudy crystalline lens with an artificial intraocular lens (IOL). The standard of treatment is implantation of a monofocal IOL, but this limits depth of focus and does not allow clear vision at both distance and near without glasses post-operatively. Multifocal and trifocal lenses split light into multiple distinct foci at near, intermediate and far distances without glasses correction. However, these lenses have been shown to reduce contrast sensitivity and impair visual field testing results, and are not recommended in patients with glaucoma. The TECNIS Symfony IOL has recently been approved by Health Canada and offers an extended range of vision with a single elongated focal point to allow patients to see at both distance and near. The lens is advertised to enhance contrast sensitivity, but it is currently unknown whether the TECNIS Symfony IOL impacts visual field testing. We will study the visual field changes in patients undergoing both TECNIS ZCB00 monofocal and TECNIS Symfony extended depth of focus IOL implantation during cataract surgery. The results of this study will impact the advice cataract surgeons give to patients with glaucoma, regarding whether this population of patients would benefit from a standard monofocal IOL implantation or an extended depth of focus TECNIS Symfony IOL implantation.

Study Overview

Detailed Description

Primary open angle glaucoma is a leading cause of blindness worldwide, and is the most common form of glaucoma. This condition involves progressive damage to the optic nerve over time and ultimately vision loss that can be detected using standard automated perimetry visual field testing. As this population ages, patients will eventually develop cataracts and require cataract surgery to replace the cloudy crystalline lens with an artificial intraocular lens. The standard of treatment is implantation of a monofocal intraocular lens (IOL), but this limits depth of focus and does not allow clear vision at both distance and near without spectacle correction post-operatively. To provide a refractive component to cataract surgery, multifocal and trifocal lenses were introduced and split light into multiple distinct foci at near, intermediate and far distances without correction. However, splitting of incoming light has the potential to decrease contrast sensitivity and increase photic phenomena. In addition, multifocal IOLs have been shown to reduce mean deviation on automated perimetry compared to monofocal IOLs and are not recommended in patients where visual field reduction may not be tolerated, such as in patients with glaucoma. The TECNIS Symfony IOL has been recently been approved by Health Canada and offers extended range of vision with a single elongated focal point, corrects for chromatic aberration and results in contrast enhancement. It is unknown whether this new IOL impacts visual field testing in glaucoma patients post cataract surgery.

The objective of this study is to compare visual field outcomes in patients choosing to undergo cataract surgery with either a TECNIS ZCB00 monofocal vs TECNIS Symfony extended depth of focus intraocular lens.

It is hypothesized that patients who undergo implantation of a TECNIS Symfony extended depth of focus intraocular lens will have impaired visual field testing (a decrease in mean deviation on Humphrey 24-2 standard automated perimetry) compared to those undergoing TECNIS ZCB00 monofocal intraocular lens implantation.

This will be a prospective cohort study.

Patients undergoing either TECNIS ZCB00 monofocal or TECNIS Symfony extended depth of focus ZXR intraocular lens insertion during cataract surgery will be recruited.

Patients will not be approached regarding the study until the patient decides which lens will be inserted during surgery. This study has no impact on a patient's choice of intraocular lens. This study will not be assigning a lens as part of the intervention.

There will be no randomization of the groups, given that patients will be choosing which lens will be implanted during surgery pre-operatively, as any other patient undergoing cataract surgery would.

There will be no blinding of study participants or of the investigators.

As per standard pre-operative assessment, patients will have ocular Biometry performed prior to surgery to assess what prism diopter lens to insert intra-operatively.

On the day of this appointment, participants will be asked to perform a 24-2 Humphrey standard automated perimetry visual field test with Swedish Interactive Threshold Algorithm (SITA) standard thresholds.

In addition, at the 1-month post-operative appointment, participants will be asked to again complete a 24-2 Humphrey visual field, in addition to the standard post-operative examination.

Study Type

Observational

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

    • Ontario
      • London, Ontario, Canada, N6A 4V2
        • Ivey Eye Institute
      • London, Ontario, Canada, N6A 4V2
        • St. Joseph's Health Care London

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

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Any adult patients undergoing cataract surgery at the Ivey Eye Clinic in London, Ontario, Canda who chose to receive a TECNIS Symfony intraocular lens implant or TECNIS monofocal ZCB00 intraocular lens implant will be approached to be enrolled in the study AFTER determining their decision to undergo cataract surgery and decision of lens implantation has been made.

Description

Inclusion Criteria:

  • Patients who have chosen to undergo elective cataract surgery in one eye with 20/40 - 20/100 vision (best corrected) in the operated eye on initial pre-op surgical assessment and with greater than or equal to 20/25 vision (best corrected) in the operated eye at 1-month post-operatively.
  • Patients who have chosen to undergo TECNIS ZCB00 monofocal intraocular lens implantation.
  • Patients who have chosen to undergo implantation of a TECNIS Symfony extended depth of focus intraocular lens.
  • Patient must be able to reliably perform visual field testing.
  • No other eye disease other than cataract.
  • Patient must be older than 18 years of age.
  • Patient must be proficient in the English language.

Exclusion Criteria:

  • Patients who are unwilling or unable to undergo visual field testing.
  • Patients with glaucoma.
  • Patients who have history of laser refractive surgery.
  • Patients who experienced an intra-operative complication.

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

  • Observational Models: Cohort
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
TECNIS Monofocal
This group of patients has chosen to undergo implantation of a TECNIS monofocal ZCB00 lens during cataract surgery. This decision was made prior to enrolment in the study. This group of patients will receive standard of care cataract surgery, as any other patient would. The sole intervention we will be undertaking is a 24-2 Humphrey visual field test prior to surgery, and a 24-2 SITA standard Humphrey visual field test after surgery at 1 month post-operatively.
Patients participate in a 24-2 SITA Standard humphrey visual field test. This includes sitting in a dark room at a visual field machine. Stimulus test points of different intensity and size will be presented to the patient, as per SITA standard protocol. The patient will indicate by pressing a button when they see the visual stimulus.
TECNIS Symfony
This group of patients has chosen to undergo implantation of a TECNIS Symfony extended depth of focus lens during cataract surgery. This decision was made prior to enrolment in the study. This group of patients will receive standard of care cataract surgery, as any other patient would. The sole intervention we will be undertaking is a 24-2 SITA standard Humphrey visual field test prior to surgery, and a 24-2 Humphrey visual field test after surgery at 1 month post-operatively.
Patients participate in a 24-2 SITA Standard humphrey visual field test. This includes sitting in a dark room at a visual field machine. Stimulus test points of different intensity and size will be presented to the patient, as per SITA standard protocol. The patient will indicate by pressing a button when they see the visual stimulus.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Deviation
Time Frame: 1 year
An overall value of the total amount of visual field loss
1 year

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pattern Standard Deviation
Time Frame: 1 year
The sum of the absolute value of the difference between the threshold value for each point and the average visual field sensitivity at each point.
1 year

Collaborators and Investigators

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

Collaborators

Investigators

  • Principal Investigator: Tony Lin, MD, Western University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the 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 (Actual)

June 1, 2018

Primary Completion (Actual)

October 1, 2019

Study Completion (Actual)

October 1, 2019

Study Registration Dates

First Submitted

April 12, 2018

First Submitted That Met QC Criteria

April 12, 2018

First Posted (Actual)

April 23, 2018

Study Record Updates

Last Update Posted (Actual)

October 2, 2019

Last Update Submitted That Met QC Criteria

October 1, 2019

Last Verified

October 1, 2019

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 111201

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

No

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

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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