Limbal Relaxing Incision Versus Toric Intraocular Lens for Corneal Astigmatism During Cataract Surgery.

November 27, 2014 updated by: Christin Henein

Limbal Relaxing Incisions Versus Toric Intraocular Lens for Keratometric Astigmatism <2.5 Diopters in Patients Undergoing Cataract Surgery and Intraocular Lens Implantation.

This study will compare toric intra-ocular lens (IOL) with limbal relaxing incisions (LRI) in correcting astigmatism in patient undergoing standard cataract surgery.

Astigmatism is unequal curvature of the eye; the eye is oval rather than spherical. Uncorrected astigmatism of greater than approximately 0.75 diopters (D) can cause visual blurring, ghosting of images or halos. Over 20% of patients undergoing cataract surgery have astigmatism which is likely to have been corrected by spectacles.

Cataract surgery involves the replacement of the natural opacifying crystalline lens with a clear artificial plastic intra-ocular lens (IOL). The lens power can be selected to correct the patient's glasses prescription. The most widely used IOLs only correct glasses at one distance i.e. either near or distance. Residual astigmatism after cataract surgery will need glasses for correction which is undesirable for many patients.

Limbal relaxing incisions (LRI) are circumferential partial thickness cuts to the clear window of the eye (cornea) during surgery. These LRIs can correct corneal astigmatism and have no additional risk of complications.

Alternatively, toric IOLs are available which correct astigmatism inside the eye. They have been available for routine use in the last few years; technology has markedly improved and the lenses have become cheaper.

Studies have suggested toric IOLs provide better vision after cataract surgery than the regular IOLs. Toric IOL are widely used in the private practice and increasingly in the National Health Service (NHS). LRIs are cost effective for treating astigmatism however their predictability is believed to be lower than toric IOLs. As there are no randomised controlled trials comparing the outcomes between LRIs and toric IOLs. This research will address this gap in knowledge and accordingly from this research future practice will be able to provide treatment to patients with information about the best outcomes.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Unknown

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Anticipated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
80

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • 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 Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United Kingdom
      • Brighton, United Kingdom, BN2 5BF
        • Recruiting
        • Sussex Eye Hospital
        • Contact:
        • Principal Investigator:
          • Mayank Nanavaty, DO, MRCSEd, FRCOphth
        • Sub-Investigator:
          • Christin Henein, MBBS, MRes, FRCOphth (part 1)
        • Sub-Investigator:
          • Saul Rajak, MBBS, PhD, FRCOphth

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Symptomatic cataract for which the patient desires surgery
  2. Corneal astigmatism of greater than or equal to 0.75 D and lesser than or equal to 2.5D.
  3. No significant ophthalmic co-morbidity which would affect the postoperative visual outcomes.

Exclusion Criteria:

  1. <18 years of age
  2. Significant ophthalmic comorbidity detrimental to final visual outcomes
  3. Not competent to give consent
  4. Concurrent use of ocular medications including lubricants
  5. Unable to attend follow ups at 1, 3, 6 and 12 months.

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

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Toric Intraocular lens
Toric intraocular lens implantation during standard cataract surgery
Device: Toric Intraocular Lens
Experimental: Limbal Relaxing Incisions
Limbal relaxing incisions during standard cataract surgery
Procedure: Limbal Relaxing Incisions

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
Unaided distance LogMAR visual acuity (UDVA)
Time Frame: 1 months
1 months
Unaided distance LogMAR visual acuity (UDVA)
Time Frame: 3 months
3 months
Unaided distance LogMAR visual acuity (UDVA)
Time Frame: 6 months
6 months
Unaided distance LogMAR visual acuity (UDVA)
Time Frame: 12 months
12 months

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Christin Henein

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Rayner Intraocular Lenses Limited

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

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 1, 2014

Primary Completion (Anticipated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2015

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 17, 2014

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 18, 2014

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
February 20, 2014

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
December 2, 2014

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 27, 2014

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2014

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • RCT135670

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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