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Vision and Balance Changes After Bilateral Implantation of Toric IOLs

Not Applicable
Recruiting
Conditions
Cataract Bilateral
Astigmatism Bilateral
Interventions
Device: Toric intraocular lens Zeiss AT TORBI
Registration Number
NCT05629078
Lead Sponsor
University of Plymouth
Brief Summary

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.

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.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
140
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 & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Toric Intraocular lensToric intraocular lens Zeiss AT TORBIToric intraocular lens- AT TORBI® 709M, to be implanted bilaterally in the cataract surgery to correct astigmatism at the same time.
Monofocal intraocular lensToric intraocular lens Zeiss AT TORBIStandard monofocals IOLs- Zeiss CT ASPHINA 409/509M, to be implanted bilaterally in the standard NHS cataract surgery without correcting the astigmatism.
Primary Outcome Measures
NameTimeMethod
Jerk from the centre of mass Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Assessed during functional activities using accelerometers

Jerk from the centre of mass Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Assessed during functional activities using accelerometers

Jerk from the centre of mass Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Assessed during functional activities using accelerometers

Secondary Outcome Measures
NameTimeMethod
Unaided visionVisit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Unaided vision measured on a LogMAR acuity chart

Rotation of IOL at visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Rotation of IOL relative to operation

Unaided vision Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Unaided vision measured on a LogMAR acuity chart

Unaided vision Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Unaided vision measured on a LogMAR acuity chart

Visual acuity Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Aided vision measured on a LogMAR acuity chart

Visual acuity Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Aided vision measured on a LogMAR acuity chart

Astigmatic power J0 Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

J0 assessed through subjective refraction and expressed in vector form

Astigmatic power J0 Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

J0 assessed through subjective refraction and expressed in vector form

Astigmatic power J45 Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

J45 assessed through subjective refraction and expressed in vector form

Astigmatic power J45 Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

J45 assessed through subjective refraction and expressed in vector form

Rotation of IOL at visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Rotation of IOL relative to Operation

Centration of IOL at Visit 2assessment at study visit 2 around 3-6 months after the first eye cataract IOL replacement surgery

Centration of IOL assessed using image analysis

Centration of IOL at Visit 3assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Centration of IOL assessed using image analysis

Visual acuity Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Aided vision measured on a LogMAR acuity chart

Mean spherical refraction Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Mean spherical refraction assessed through subjective refraction

Mean spherical refraction Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Mean spherical refraction assessed through subjective refraction

Mean spherical refraction Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Mean spherical refraction assessed through subjective refraction

Astigmatic power J0 Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

J0 assessed through subjective refraction and expressed in vector form

Contrast sensitivity Visit 2First reassessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Contrast sensitivity measured in log units

Centration of IOL at Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Centration of IOL assessed using image analysis

Cataract related quality of lifeassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Using Catract patient reported outcome measure CAT-PROM5 questionnaire

Astigmatic power J45 Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

J45 assessed through subjective refraction and expressed in vector form

Contrast sensitivity Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Contrast sensitivity measured in log units

Contrast sensitivity Visit 3Final reassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Contrast sensitivity measured in log units

Rotation of IOL at visit 2First assessment will be carried out at study visit 2 around 3-6 months after the first cataract IOL replacement surgery

Rotation of IOL relative to operation

Tilt of IOL at Visit 1Baseline assessment will be carried out at study visit 1 before the cataract surgery

Tilt of IOL assessed using image analysis

Tilt of IOL at Visit 2assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Tilt of IOL assessed using image analysis

Tilt of IOL at Visit 3assessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Tilt of IOL assessed using image analysis

Fear of fallingassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Fear of falling measured using revised fear of falling questionnaire (FFR)

Risk of fallassessment at study visit 3 around 3-6 months after the second eye cataract IOL replacement surgery

Risk of fall in daily activities measured by Short Fall Efficacy Scale Questionnaire (Short FFS-I)

Trial Locations

Locations (1)

Royal Eye Infirmary

🇬🇧

Plymouth, United Kingdom

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