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

Study Type

Interventional

Enrollment (Anticipated)

80

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 Contact

Study Locations

      • 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

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
Intervention / Treatment
Experimental: Toric Intraocular lens
Toric intraocular lens implantation during standard cataract surgery
Experimental: Limbal Relaxing Incisions
Limbal relaxing incisions during standard cataract surgery

What is the study measuring?

Primary Outcome Measures

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.

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

June 1, 2014

Primary Completion (Anticipated)

December 1, 2015

Study Registration Dates

First Submitted

February 17, 2014

First Submitted That Met QC Criteria

February 18, 2014

First Posted (Estimate)

February 20, 2014

Study Record Updates

Last Update Posted (Estimate)

December 2, 2014

Last Update Submitted That Met QC Criteria

November 27, 2014

Last Verified

November 1, 2014

More Information

Terms related to this study

Other Study ID 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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