Implantation of Capsular Tension Ring in Primary Angle Closure Patients With Zonular Laxity or Dialysis

Primary angle closure glaucoma (PACG) is the main type of glaucoma in China, which includes acute and chronic PACG. According to the International Society of Geographical and Epidemiological Ophthalmology (ISGEO), this spectrum of disease is divided into acute angle closure crisis (AACC), primary angle closure suspect (PACS), primary angle closure (PAC) and PACG. Previous researchers have reported that with the wider use of lens extraction and intraocular lens (IOL) implantation combined with anti-glaucoma surgery in the treatment of PAC and PACG, the prevalence of zonular laxity or dialysis in primary angle closure disease (PACD) was found to be relatively high. In one of the studies performed by the investigators, the proportion of zonular laxity or dialysis was 46.2%, significantly higher than that in the age-related cataract patients (control group), which was 6.0%. In PACD patients with zonular laxity or dialysis, whether or not should the investigators implant capsular tension ring (CTR), the efficacy and safety of CTR implantation, and if there is any difference in the prevalence of complications during and after surgery between patients with and without CTR implantation remain unclear. The purpose of this study was to investigate the efficacy and safety of CTR implantation in PACD patients with zonular laxity and zonular dialysis ≤ 4 clocks.

Study Overview

• Status: Not yet recruiting
• Conditions: Glaucoma; Angle-Closure
• Intervention / Treatment: Procedure: Capsular tension ring implantation; Procedure: No capsular tension ring implantation

Detailed Description

Patients with PACD who are scheduled to have phacoemulsification and IOL implantation combined with goniosynechialysis are recruited. All recruited patients attended comprehensive eye examinations and interviews. Past history of ocular and systemic diseases, family and personal history, history of ocular trauma and surgery were interviewed. And the patients underwent ophthalmic examinations including visual acuity tests (presenting visual acuity [PVA] and best-corrected visual acuity [BCVA]), subjective refraction, intraocular pressure (IOP) measurements, slit-lamp examination, fundus photography, gonioscopy, ocular biometry using IOL Master 700, ultrasound biomicroscopy, anterior segment optical coherence tomography (ASOCT) imaging. All patients provide informed consent for inclusion in the study.

All surgery procedures were performed by the same surgeons (CYQ) using the same standard operation procedure. All patients use the same type of foldable IOL calculated using SRK/T formula. During the surgery, patients with wrinkling of the anterior capsule (multiple sinusoidal folds were formed) during continuous curvilineal capsulorhexis (CCC) at the needle or forceps tip but without infolding of peripheral capsule or visualisation of the capsular equator during the cortical or nuclear removal, or, wrinkling of the anterior capsule during CCC with infolding of peripheral capsule and visualisation of the capsular equator ≤ 4 clocks of range during the cortical or nuclear removal, were finally included in the study and randomly assigned (using a random-number table generated by SAS) with equal probability to either CTR group (with CTR implantation during the surgery) and control group (without CTR implantation during the surgery). All patients included in the CTR group use the same type of CTR. The investigators recorded the complications during the surgery including vitreous prolapse, hyphema, vitreous hemorrhage, damage of iris and lens capsule, et al.

Postoperatively, all patients received similar routine medication comprising topical prednisolone acetate (six times a day for 1 week and tapered down by 1 time every week), topical levofloxacin hydrochloride (four times a day for 1 month), and Tobramycin and Dexamethasone Eye Ointment (1 time every night for 1 month).

Postoperative examinations were performed at 1 day, 1 week, 1 months, 3 months, 6 months and 12 months. During the follow-up visits, a complete ophthalmic examination was performed including PVA, BCVA, subjective refraction, non-contact IOP measurement, slit-lamp examination, slit-lamp photography after pupil dilation, ASOCT, gonioscopy, and fundus imaging.

• Study Type: Interventional
• Enrollment (Anticipated): 156
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Chunyan Qiao, M.D.; Phone Number: 86-17610678637; Email: chunyan_qiao@163.com

Study Locations

• China
  • Beijing, China, 100730
    • Beijing Tongren Hospital
    • Contact: Chunyan Qiao, M.D.; Phone Number: 86017610678637; Email: chunyan_qiao@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 79 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age: 45-79 years old
• Continuous cases diagnosed with AACC, PACS, PAC and PACG in glaucoma department of Beijing Tongren Hospital from October 1st, 2022 to December 31th, 2024 and undergo phacoemulsification lens extraction and intraocular lens implantation combined with goniosynechialysis
• Wrinkling of the anterior capsule during manual continuous circular capsulorhexis (CCC) but without infolding of peripheral capsule or visualization of the capsular equator, or, wrinkling of the anterior capsule during manual capsulorhexis and combined with visualization of capsular equator and infolding of peripheral capsule ≤ 4 clocks (lens subluxation)
• The eye of each subject that meet the inclusion criteria is included and if both eyes meet the inclusion criteria, the first eye that undergo the surgery is included

Exclusion Criteria:

• Past history of intraocular surgeries including trabeculectomy, peripheral iridotomy, glaucoma valve implantation, vitrectomy, and so on
• Past history of laser peripheral iridotomy or iridoplasty
• Past history of ocular trauma or signs referring to ocular trauma
• Ocular diseases that may cause zonulopathy, including choroidal detachment, retinal detachment, ciliary body detachment, intraocular tumor and so on
• Lens related secondary glaucoma, including spherophakia, Marfan syndrome, homocystinuria and son on
• Other secondary angle closure glaucoma, including neovascular glaucoma, iritis related secondary glaucoma and so on
• Visualization of capsular equator and infolding of peripheral capsule > 4 clocks during the surgery
• Anterior or posterior capsule rupture during the surgery which makes it impossible for CTR implantation

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
Experimental: With capsular tension ring implantation; We performed phacoemulsification lens extraction and intraocular lens implantation with capsular tension ring implantation combined with goniosynechialysis.	Procedure: Capsular tension ring implantation; Capsular tension ring implantation during phacoemulsification lens extraction and intraocular lens implantation combined with goniosynechialysis in included angle closure patients.
Other: Without capsular tension ring implantation; We performed phacoemulsification lens extraction and intraocular lens implantation without capsular tension ring implantation combined with goniosynechialysis.	Procedure: No capsular tension ring implantation; No capsular tension ring implantation during phacoemulsification lens extraction and intraocular lens implantation combined with goniosynechialysis in included angle closure patients.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spherical equivalent	Sphere +1/2 cylinder obtained from subjective refraction	baseline
Spherical equivalent	Sphere +1/2 cylinder obtained from subjective refraction	1 month after the surgery
Spherical equivalent	Sphere +1/2 cylinder obtained from subjective refraction	3 months after the surgery
Spherical equivalent	Sphere +1/2 cylinder obtained from subjective refraction	6 months after the surgery
Spherical equivalent	Sphere +1/2 cylinder obtained from subjective refraction	12 months after the surgery
Area of anterior capsulorhexis	Area of anterior capsulorhexis measured using slit-lamp photography	1 week after the surgery
Area of anterior capsulorhexis	Area of anterior capsulorhexis measured using slit-lamp photography	1 month after the surgery
Area of anterior capsulorhexis	Area of anterior capsulorhexis measured using slit-lamp photography	3 months after the surgery
Area of anterior capsulorhexis	Area of anterior capsulorhexis measured using slit-lamp photography	6 months after the surgery
Area of anterior capsulorhexis	Area of anterior capsulorhexis measured using slit-lamp photography	12 months after the surgery
Assessment of posterior capsular opacification	Assessment of posterior capsular opacification using slit-lamp photography	1 week after the surgery
Assessment of posterior capsular opacification	Assessment of posterior capsular opacification using slit-lamp photography	1 month after the surgery
Assessment of posterior capsular opacification	Assessment of posterior capsular opacification using slit-lamp photography	3 months after the surgery
Assessment of posterior capsular opacification	Assessment of posterior capsular opacification using slit-lamp photography	6 months after the surgery
Assessment of posterior capsular opacification	Assessment of posterior capsular opacification using slit-lamp photography	12 months after the surgery
The extent of iris-trabecular contact	The extent of iris-trabecular contact assessed by gonioscopy	baseline
The extent of iris-trabecular contact	The extent of iris-trabecular contact assessed by gonioscopy	1 month after the surgery
The extent of iris-trabecular contact	The extent of iris-trabecular contact assessed by gonioscopy	3 months after the surgery
The extent of iris-trabecular contact	The extent of iris-trabecular contact assessed by gonioscopy	6 months after the surgery
The extent of iris-trabecular contact	The extent of iris-trabecular contact assessed by gonioscopy	12 months after the surgery
The extent of peripheral anterior synechia	The extent of peripheral anterior synechia assessed by gonioscopy	baseline
The extent of peripheral anterior synechia	The extent of peripheral anterior synechia assessed by gonioscopy	1 month after the surgery
The extent of peripheral anterior synechia	The extent of peripheral anterior synechia assessed by gonioscopy	3 months after the surgery
The extent of peripheral anterior synechia	The extent of peripheral anterior synechia assessed by gonioscopy	6 months after the surgery
The extent of peripheral anterior synechia	The extent of peripheral anterior synechia assessed by gonioscopy	12 months after the surgery
Corneal thickness	Corneal thickness obtained by IOL Master 700	baseline
Central anterior chamber depth	Central anterior chamber depth obtained by IOL Master 700	baseline
Lens thickness	Lens thickness obtained by IOL Master 700	baseline
Axial Length	Axial Length obtained by IOL Master 700	baseline
Refractive prediction error	Refractive prediction error obtained by IOL Master 700	baseline
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	baseline
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	1 week after the surgery
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	1 month after the surgery
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	3 months after the surgery
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	6 months after the surgery
Anterior chamber depth	Anterior chamber depth obtained by anterior segment optical coherence tomography	12 months after the surgery
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	baseline
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	1 week after the surgery
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	1 month after the surgery
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	3 months after the surgery
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	6 months after the surgery
Angle opening distance	Angle opening distance obtained by anterior segment optical coherence tomography	12 months after the surgery
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	baseline
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	1 week after the surgery
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	1 month after the surgery
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	3 months after the surgery
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	6 months after the surgery
Trabecular-iris space area	Trabecular-iris space area obtained by anterior segment optical coherence tomography	12 months after the surgery
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	baseline
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	1 week after the surgery
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	1 month after the surgery
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	3 months after the surgery
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	6 months after the surgery
Trabecular-iris angle	Trabecular-iris angle obtained by anterior segment optical coherence tomography	12 months after the surgery
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	baseline
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	1 week after the surgery
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	1 month after the surgery
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	3 months after the surgery
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	6 months after the surgery
Anterior chamber width	Anterior chamber width obtained by anterior segment optical coherence tomography	12 months after the surgery
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	baseline
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	1 week after the surgery
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	1 month after the surgery
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	3 months after the surgery
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	6 months after the surgery
Iris thickness	Iris thickness obtained by anterior segment optical coherence tomography	12 months after the surgery
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	baseline
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	1 week after the surgery
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	1 month after the surgery
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	3 months after the surgery
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	6 months after the surgery
Iris cross-sectional area	Iris cross-sectional area obtained by anterior segment optical coherence tomography	12 months after the surgery
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	baseline
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	1 week after the surgery
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	1 month after the surgery
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	3 months after the surgery
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	6 months after the surgery
Iris curvature	Iris curvature obtained by anterior segment optical coherence tomography	12 months after the surgery
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	baseline
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	1 week after the surgery
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	1 month after the surgery
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	3 months after the surgery
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	6 months after the surgery
Lens thickness	Lens thickness obtained by anterior segment optical coherence tomography	12 months after the surgery
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	baseline
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	1 week after the surgery
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	1 month after the surgery
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	3 months after the surgery
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	6 months after the surgery
Lens vault	Lens vault obtained by anterior segment optical coherence tomography	12 months after the surgery
The distance between intraocular lens and the posterior capsular	The distance between intraocular lens and the posterior capsular obtained by CASIA2 anterior segment optical coherence tomography	1 week after the surgery
The distance between intraocular lens and the posterior capsular	The distance between intraocular lens and the posterior capsular obtained by CASIA2 anterior segment optical coherence tomography	1 month after the surgery
The distance between intraocular lens and the posterior capsular	The distance between intraocular lens and the posterior capsular obtained by CASIA2 anterior segment optical coherence tomography	3 months after the surgery
The distance between intraocular lens and the posterior capsular	The distance between intraocular lens and the posterior capsular obtained by CASIA2 anterior segment optical coherence tomography	6 months after the surgery
The distance between intraocular lens and the posterior capsular	The distance between intraocular lens and the posterior capsular obtained by CASIA2 anterior segment optical coherence tomography	12 months after the surgery
Intraocular lens inclination angle	Intraocular lens inclination angle obtained by CASIA2 anterior segment optical coherence tomography	1 week after the surgery
Intraocular lens inclination angle	Intraocular lens inclination angle obtained by CASIA2 anterior segment optical coherence tomography	1 month after the surgery
Intraocular lens inclination angle	Intraocular lens inclination angle obtained by CASIA2 anterior segment optical coherence tomography	3 months after the surgery
Intraocular lens inclination angle	Intraocular lens inclination angle obtained by CASIA2 anterior segment optical coherence tomography	6 months after the surgery
Intraocular lens inclination angle	Intraocular lens inclination angle obtained by CASIA2 anterior segment optical coherence tomography	12 months after the surgery
Effective intraocular lens position	Effective intraocular lens position obtained by CASIA2 anterior segment optical coherence tomography	1 week after the surgery
Effective intraocular lens position	Effective intraocular lens position obtained by CASIA2 anterior segment optical coherence tomography	1 month after the surgery
Effective intraocular lens position	Effective intraocular lens position obtained by CASIA2 anterior segment optical coherence tomography	3 months after the surgery
Effective intraocular lens position	Effective intraocular lens position obtained by CASIA2 anterior segment optical coherence tomography	6 months after the surgery
Effective intraocular lens position	Effective intraocular lens position obtained by CASIA2 anterior segment optical coherence tomography	12 months after the surgery
The distance between ciliary body and the equator of lens at 3 o'clock position	The distance between ciliary body and the equator of lens at 3 o'clock position obtained by ultrasound biomicroscopy	baseline
The distance between ciliary body and the equator of lens at 6 o'clock position	The distance between ciliary body and the equator of lens at 6 o'clock position obtained by ultrasound biomicroscopy	baseline
The distance between ciliary body and the equator of lens at 9 o'clock position	The distance between ciliary body and the equator of lens at 9 o'clock position obtained by ultrasound biomicroscopy	baseline
The distance between ciliary body and the equator of lens at 12 o'clock position	The distance between ciliary body and the equator of lens at 12 o'clock position obtained by ultrasound biomicroscopy	baseline
Incidence of complications	Incidence of complications including posterior capsular opacification (PCO), IOL tilt, capsule contraction syndrome, et al.	1 month after the surgery
Incidence of complications	Incidence of complications including PCO, IOL tilt, capsule contraction syndrome, et al.	3 months after the surgery
Incidence of complications	Incidence of complications including PCO, IOL tilt, capsule contraction syndrome, et al.	6 months after the surgery
Incidence of complications	Incidence of complications including PCO, IOL tilt, capsule contraction syndrome, et al.	12 months after the surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presenting visual acuity	Presenting visual acuity with or without glasses	baseline
Presenting visual acuity	Presenting visual acuity with or without glasses	1 day after the surgery
Presenting visual acuity	Presenting visual acuity with or without glasses	1 week after the surgery
Presenting visual acuity	Presenting visual acuity with or without glasses	1 month after the surgery
Presenting visual acuity	Presenting visual acuity with or without glasses	3 months after the surgery
Presenting visual acuity	Presenting visual acuity with or without glasses	6 months after the surgery
Presenting visual acuity	Presenting visual acuity with or without glasses	12 months after the surgery
Best corrected visual acuity	Visual acuity with refractive correction	baseline
Best corrected visual acuity	Visual acuity with refractive correction	1 month after the surgery
Best corrected visual acuity	Visual acuity with refractive correction	3 months after the surgery
Best corrected visual acuity	Visual acuity with refractive correction	6 months after the surgery
Best corrected visual acuity	Visual acuity with refractive correction	12 months after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	baseline
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	1 day after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	1 week after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	1 month after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	3 months after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	6 months after the surgery
Intraocular pressure	Intraocular pressure obtained by non-contact tonometer	12 months after the surgery
Number of anti-glaucoma medications	Number of anti-glaucoma medications	1 week after the surgery
Number of anti-glaucoma medications	Number of anti-glaucoma medications	1 month after the surgery
Number of anti-glaucoma medications	Number of anti-glaucoma medications	3 months after the surgery
Number of anti-glaucoma medications	Number of anti-glaucoma medications	6 months after the surgery
Number of anti-glaucoma medications	Number of anti-glaucoma medications	12 months after the surgery
Vertical cup-to-disc ratio	Vertical cup-to-disc ratio evaluated by fundus photography	baseline
Vertical cup-to-disc ratio	Vertical cup-to-disc ratio evaluated by fundus photography	1 month after the surgery
Vertical cup-to-disc ratio	Vertical cup-to-disc ratio evaluated by fundus photography	6 months after the surgery
Vertical cup-to-disc ratio	Vertical cup-to-disc ratio evaluated by fundus photography	12 months after the surgery

Collaborators and Investigators

• Sponsor: Beijing Tongren Hospital

Study record dates

Study Major Dates

• Study Start (Anticipated): March 1, 2023
• Primary Completion (Anticipated): October 1, 2025
• Study Completion (Anticipated): October 1, 2025

Study Registration Dates

• First Submitted: September 3, 2022
• First Submitted That Met QC Criteria: September 14, 2022
• First Posted (Actual): September 15, 2022

Study Record Updates

• Last Update Posted (Estimate): March 7, 2023
• Last Update Submitted That Met QC Criteria: March 6, 2023
• Last Verified: March 1, 2023

More Information

Terms related to this study

• Keywords: safety; efficacy; lens subluxation; capsular tension ring; angle closure; zonular laxity; zonular dialysis
• Additional Relevant MeSH Terms: Eye Diseases; Ocular Hypertension; Glaucoma
• Other Study ID Numbers: BeijingTH-CTR

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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