Impact of Capsular Tension Ring Implantation on Intraocular Lens Position

Impact of Capsular Tension Ring Implantation on Intraocular Lens Tilt and Decentration in Cataract Patients With High Myopia: a Randomized Controlled Trial

This is a randomized controlled trial to investigate the effect of capsular tension ring (CTR) implantation on intraocular lens (IOL) tilt and decentration in cataract patients with high myopia.

Study Overview

• Status: Recruiting
• Conditions: Cataract; High Myopia
• Intervention / Treatment: Procedure: phacoemulsification combined with IOL and CTR implantation; Procedure: phacoemulsification combined with IOL implantation

Detailed Description

Exact positioning and alignment of the IOL with the visual axis are the prerequisites of high-quality visual performance after cataract surgery. A certain degree of IOL tilt and decentration occur after uneventful cataract surgery, most of which are clinically tolerant. However, the relatively large capsular bag volume, zonular weakness, and vitreous liquefaction in cataract patients with high myopia may increase the IOL position instability, such as tilt, decentration and even dislocation, leading to the deterioration of visual function. Thus, how to improve the long-term stability of IOL position in high myopic cataract patients is an urgent issue to be addressed.

Previous studies have shown that CTR implantation during cataract surgery can increase the IOL stability in patients with normal axial length; however, its impact on IOL position of cataract patients with high myopia remains unclear.

In this randomized clinical trial, patients who meet the inclusion criteria will be divided into three layers according to the axial length:

(1)26mm≤AL<28mm (2)28mm≤AL<30mm (3)AL≥30mm

We are going to recruit 186 patients in total, with 62 patients in each layer. Patients on each layer will be randomly divided into experimental group (CTR implantation) and control group (only IOL implantation). If both eyes of a patient meet the inclusion criteria, only the first operated eye is included in the statistics analysis.

All included patients will be followed up at 1 week, 1 month, 3 months, 6 months, and 1 year postoperatively. Visual acuity, IOL tilt, IOL decentration, posterior capsule attachment with IOL, anterior capsule contraction, posterior capsular opacification, and visual quality will be measured and compared between the experimental group and the control group at different timepoints.

• Study Type: Interventional
• Enrollment (Anticipated): 186
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510060
      • Recruiting
      • Zhongshan Ophthalmic Center, Sun Yat-sen University
      • Contact: Xuhua Tan, PhD; Phone Number: +86-13926019722; Email: doctxh@163.com
      • Contact: Haowen Lin, Master; Phone Number: +86-13275000978; Email: 962773724@qq.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. > 18 years old;
2. axis length≥26mm;
3. Visually significant cataract;
4. The patient is willing and able to complete all necessary follow-ups and examinations.

Exclusion Criteria:

1. Intraoperative or postoperative complications: such as intraoperative posterior capsular rupture, zonular dehiscence, secondary glaucoma, endophthalmitis, etc.;
2. Other ocular comorbidity: such as keratopathy, glaucoma, uveitis, retinopathy, lens dislocation and ocular trauma, etc.;
3. History of intraocular surgery;
4. Severe systemic diseases: such as severe hypertension, diabetes, heart disease, Alzheimer's, Parkinson, etc.;
5. Any condition that the study physician considers to be an impediment to the clinical trial.

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: IOL plus CTR Patients will undergo phacoemulsification combined with IOL and CTR implantation.	Procedure: phacoemulsification combined with IOL and CTR implantation; Device: CTR (276001G； OPHTEC BV, Netherlands) Device: IOL (920H; Rayner Intracular Lenses Limited，Hove，East Sussex，UK) All patients undergo uneventful phacoemulsification by a 3.0 mm temporal transparent corneal incision using Centurion Vision System (Alcon Laboratories, Fort Worth, TX, USA). After the nucleus and cortex are removed, a capsular tension ring is implanted in the capsular bag and then IOL is implanted.
Placebo Comparator: single IOL Patients will undergo phacoemulsification combined with IOL implantation.	Procedure: phacoemulsification combined with IOL implantation; Device: IOL (920H; Rayner Intracular Lenses Limited，Hove，East Sussex，UK) All patients undergo uneventful phacoemulsification by a 3.0 mm temporal transparent corneal incision using Centurion Vision System (Alcon Laboratories, Fort Worth, TX, USA). After the nucleus and cortex are removed, IOL is implanted in the capsular bag.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
IOL dencentration	Measured by anterior segment OCT (CASIA2)	3 months after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
IOL dencentration	Measured by anterior segment OCT (CASIA2)	Baseline (before surgery), 1 week, 1 month, 6 months, 1 year after surgery
IOL tilt	Measured by anterior segment OCT (CASIA2)	Baseline (before surgery), 1 week, 1 month, 3 months, 6 months, 1 year after surgery
Anterior capsule contraction	Compare the area of anterior capsule opening recorded by slit lamp photograph and analyzed by Image J software.	Baseline, 1 week, 1 month, 3 months, 6 months, 1 year after surgery
Posterior capsule attachment with IOL	Measured by anterior segment OCT (CASIA2) and analyzed by Image J software.	1 week, 1 month, 3 months, 6 months, 1 year after surgery
Posterior capsular opacification	Recorded by slit lamp photograph and analyzed by EPCO2000 analysis software.	1 week, 1 month, 3 months, 6 months, 1 year after surgery
BCVA	BCVA is evaluated with ETDRS visual acuity chart.	Baseline (before surgery), 1 week, 1 month, 3 months, 6 months, 1 year after surgery
Optical quality	Measured by OPD-SCAN III.	Baseline (before surgery), 1 week, 1 month, 3 months, 6 months, 1 year after surgery
Visual function	Measured by visual function assessment questionnaires.	3 months, 6 months, 1 year after surgery

Collaborators and Investigators

• Sponsor: Xuhua Tan

Study record dates

Study Major Dates

• Study Start (Actual): December 16, 2021
• Primary Completion (Anticipated): June 1, 2023
• Study Completion (Anticipated): December 1, 2024

Study Registration Dates

• First Submitted: December 2, 2021
• First Submitted That Met QC Criteria: December 16, 2021
• First Posted (Actual): December 17, 2021

Study Record Updates

• Last Update Posted (Actual): April 18, 2023
• Last Update Submitted That Met QC Criteria: April 17, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Refractive Errors; Cataract; Myopia
• Other Study ID Numbers: 2021KYPJ128

Drug and device information, study documents

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