Vision and Balance Changes After Bilateral Implantation of Toric IOLs

Vision and Balance Changes After Bilateral Implantation of Toric Versus Non-Toric Intraocular Lenses in Cataract Patients With Astigmatism

Cataracts are the major cause of blindness in the world. Cataract surgery, being the most performed surgery in the world today, provide correction by extracting the natural lens from its capsular bag and replaced by an artificial intraocular lens (IOL) implantation. In the UK, almost all patients undergoing cataract surgery by the NHS are given monofocal intraocular lenses (IOLs) which do not correct corneal astigmatic error. It is estimated that around 20% of the population has over 1.50DC of corneal astigmatism. Uncorrected astigmatism not only increase spectacle dependency and reduce quality of life post surgically, but it also adversely affects the overall economic costs. Specialised toric IOLs offer the opportunity to correct pre-existing corneal astigmatism. Previous work has shown a link between reduced vision and balance or mobility. Full correction of refractive error may have greater impact on lifestyle than previously thought.

Study Overview

• Status: Recruiting
• Conditions: Cataract Bilateral; Astigmatism Bilateral
• Intervention / Treatment: Device: Toric intraocular lens Zeiss AT TORBI

Detailed Description

This is a single centre, parallel randomized controlled trial study comparing the dynamic stability and visual outcomes of cataract patient with astigmatism implanted with mono-focal Toric versus non-Toric IOLs.

140 cataracts patients with astigmatism awaiting cataract correction surgery at the Royal Eye infirmary of the University Hospitals of Plymouth NHS Trust will be recruited in this study over a two year period. The participants will be randomly assigned to be implanted with either Toric IOLs or standard non-Toric IOLs. Three additional study visits will be arranged for them. One visit before the cataract surgery, second visit at three to six months after the first eye cataract surgery and third visit at three to six months after the second eye cataract surgery. The primary assessment outcome is dynamic balance measured by movement sensors (accelerometer) during walk and turn, crossing over obstacle and stair walking. The secondary outcomes include eye tracking during movement activities, visual functions, risk of fall questionnaires and vision-specific quality of life questionnaire.

This project is funded by Carl Zeiss Meditec AG, led by the University of Plymouth and sponsored by University Hospitals Plymouth NHS Trust . The project also involves collaboration with the University of Glasgow and the Plymouth Marjon University.

• Study Type: Interventional
• Enrollment (Estimated): 140
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Sherrie T Choy, MSc; Phone Number: 07903692005; Email: sherrie.choy@plymouth.ac.uk

Study Locations

• United Kingdom
  • Plymouth, United Kingdom
    • Recruiting
    • Royal Eye Infirmary
    • Contact: Nabil Habib; Email: nabil.habib@nhs.net

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• bilateral significant corneal astigmatism >1.0D
• on waiting list for bilateral cataract surgery in NHS

Exclusion Criteria:

• pre-existing eye pathology which may be aggravated by intraocular implant
• previous intraocular/ corneal surgery
• History of uveitis, glaucoma, proliferative diabetic retinopathy or IDDM, pseudoexfoliation, macular degeneration that may affect potential best corrected visual acuity of 20/40 or better
• Micropthalmia
• corneal decompensation or endothelial insufficiency
• pars planitis
• high myopia
• participants using a systematic medication that is known to cause ocular side effects
• participated in a concurrent clinical trial or have participated in an opthalmology clinical trial within the last 30 days
• unable or not willing to cooperate for the follow up period
• pregnant women
• unable to give informed consent
• unable to walk with or without walking aids independently for at least 20m
• unable to walk up/down stairs independently using aids or handrail

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Toric Intraocular lens; Toric intraocular lens- AT TORBI® 709M, to be implanted bilaterally in the cataract surgery to correct astigmatism at the same time.	Device: Toric intraocular lens Zeiss AT TORBI; Intraocular lenses are medical devices that are implanted in patients during cataract surgery. At Plymouth University NHS trust the standard lens is a monofocal non-Toric lens unless the patient has astigmatism greater than 4.00D. This study involves implantation of a toric lens in the intervention group where astigmatism is greater than 1.00D. The lens is called the toric IOLS- Zeiss AT TORBI, will be implanted bilaterally instead of standard monofocal IOLs- Zeiss CT ASPHINA, used in routine cataract surgery within NHS.; Other Names: Monofocal non-toric intraocular lens Zeiss CT ASPHINA 409/509M
Active Comparator: Monofocal intraocular lens; Standard monofocals IOLs- Zeiss CT ASPHINA 409/509M, to be implanted bilaterally in the standard NHS cataract surgery without correcting the astigmatism.	Device: Toric intraocular lens Zeiss AT TORBI; Intraocular lenses are medical devices that are implanted in patients during cataract surgery. At Plymouth University NHS trust the standard lens is a monofocal non-Toric lens unless the patient has astigmatism greater than 4.00D. This study involves implantation of a toric lens in the intervention group where astigmatism is greater than 1.00D. The lens is called the toric IOLS- Zeiss AT TORBI, will be implanted bilaterally instead of standard monofocal IOLs- Zeiss CT ASPHINA, used in routine cataract surgery within NHS.; Other Names: Monofocal non-toric intraocular lens Zeiss CT ASPHINA 409/509M

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Jerk from the centre of mass Visit 1	Assessed during functional activities using accelerometers	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Jerk from the centre of mass Visit 2	Assessed during functional activities using accelerometers	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Jerk from the centre of mass Visit 3	Assessed during functional activities using accelerometers	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Unaided vision Visit 1	Unaided vision measured on a LogMAR acuity chart	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Unaided visionVisit 2	Unaided vision measured on a LogMAR acuity chart	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Unaided vision Visit 3	Unaided vision measured on a LogMAR acuity chart	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Visual acuity Visit 1	Aided vision measured on a LogMAR acuity chart	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Visual acuity Visit 2	Aided vision measured on a LogMAR acuity chart	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Visual acuity Visit 3	Aided vision measured on a LogMAR acuity chart	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Mean spherical refraction Visit 1	Mean spherical refraction assessed through subjective refraction	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Mean spherical refraction Visit 2	Mean spherical refraction assessed through subjective refraction	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Mean spherical refraction Visit 3	Mean spherical refraction assessed through subjective refraction	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Astigmatic power J0 Visit 1	J0 assessed through subjective refraction and expressed in vector form	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Astigmatic power J0 Visit 2	J0 assessed through subjective refraction and expressed in vector form	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Astigmatic power J0 Visit 3	J0 assessed through subjective refraction and expressed in vector form	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Astigmatic power J45 Visit 1	J45 assessed through subjective refraction and expressed in vector form	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Astigmatic power J45 Visit 2	J45 assessed through subjective refraction and expressed in vector form	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Astigmatic power J45 Visit 3	J45 assessed through subjective refraction and expressed in vector form	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Contrast sensitivity Visit 1	Contrast sensitivity measured in log units	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Contrast sensitivity Visit 2	Contrast sensitivity measured in log units	First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Contrast sensitivity Visit 3	Contrast sensitivity measured in log units	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Rotation of IOL at visit 1	Rotation of IOL relative to operation	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Rotation of IOL at visit 2	Rotation of IOL relative to operation	First assessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery
Rotation of IOL at visit 3	Rotation of IOL relative to Operation	Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Tilt of IOL at Visit 1	Tilt of IOL assessed using image analysis	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Tilt of IOL at Visit 2	Tilt of IOL assessed using image analysis	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Tilt of IOL at Visit 3	Tilt of IOL assessed using image analysis	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Centration of IOL at Visit 1	Centration of IOL assessed using image analysis	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Centration of IOL at Visit 2	Centration of IOL assessed using image analysis	assessment at study visit 2 around 3-6 months after the first eye cataract IOL replacement surgery
Centration of IOL at Visit 3	Centration of IOL assessed using image analysis	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Fear of falling	Fear of falling measured using revised fear of falling questionnaire (FFR)	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Fear of falling	Fear of falling measured using revised fear of falling questionnaire (FFR)	assessment at study visit 2 around 3-6 months after the first eye cataract IOL replacement surgery
Fear of falling	Fear of falling measured using revised fear of falling questionnaire (FFR)	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Risk of fall	Risk of fall in daily activities measured by Short Fall Efficacy Scale Questionnaire (Short FFS-I)	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Risk of fall	Risk of fall in daily activities measured by Short Fall Efficacy Scale Questionnaire (Short FFS-I)	assessment at study visit 2 around 3-6 months after the first eye cataract IOL replacement surgery
Risk of fall	Risk of fall in daily activities measured by Short Fall Efficacy Scale Questionnaire (Short FFS-I)	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery
Cataract related quality of life	Using Catract patient reported outcome measure CAT-PROM5 questionnaire	Baseline assessment will be carried out at study visit 1 before the cataract surgery
Cataract related quality of life	Using Catract patient reported outcome measure CAT-PROM5 questionnaire	assessment at study visit 2 around 3-6 months after the first eye cataract IOL replacement surgery
Cataract related quality of life	Using Catract patient reported outcome measure CAT-PROM5 questionnaire	assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Collaborators and Investigators

• Sponsor: University of Plymouth
• Collaborators: Carl Zeiss Meditec AG; University Hospital Plymouth NHS Trust; Glasgow Caledonian University; University of St Mark and St John Plymouth
• Investigators: Principal Investigator: Nabil Habib, MB ChB(Hons), Royal Eye Infirmay, University Hosptials Plymouth NHS Trust; Study Chair: Phillip Buckhurst, PhD, University of Plymouth; Study Director: Catriona MacLennan, PhD, Glasgow Caledonian Unviersity; Study Director: Gary L.K. Shum, PhD, Plymouth Marjon University; Study Director: Hetal Buckhurst, PhD, University of Plymouth

Study record dates

Study Major Dates

• Study Start (Actual): January 12, 2024
• Primary Completion (Estimated): December 30, 2024
• Study Completion (Estimated): July 31, 2025

Study Registration Dates

• First Submitted: March 4, 2021
• First Submitted That Met QC Criteria: November 16, 2022
• First Posted (Actual): November 29, 2022

Study Record Updates

• Last Update Posted (Actual): March 28, 2024
• Last Update Submitted That Met QC Criteria: March 27, 2024
• Last Verified: March 1, 2024

More Information

Terms related to this study

• Keywords: quality of life; balance; fear of falling; visual function; toric intraocular lens; dynamic stability; post-cataract surgery
• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Refractive Errors; Cataract; Astigmatism
• Other Study ID Numbers: 286913

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: no plan to share IPD

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No