A Randomized Study of Intraocular Caliper-assisted Capsulotomy for Age-related Cataract Patients With Corneal Limbus Opacity

A Randomized Controlled Trial Comparing Intraocular Caliper-assisted Capsulotomy Versus Verion Navigation System-assisted Capsulotomy for Age-related Cataract With Corneal Limbus Opacity

The purpose of this study is to compare the accuracy of capsulotomy assisted by intraocular caliper and Verion navigation system in phacoemulsification surgery and postoperative visual quality for age-related cataract patients with corneal limbus opacity.

Study Overview

• Status: Not yet recruiting
• Conditions: Cataract Extraction
• Intervention / Treatment: Procedure: Intraocular caliper-assisted capsulotomy; Procedure: Verion navigation system-assisted capsulotomy

Detailed Description

Continuous curvilinear capsulorhexis (CCC) is an important and technically challenging procedure in cataract surgery. Too large or too small capsulorhexis can increase the incidence of intraoperative and postoperative complications.

In recent years, the image projection device Verion navigation system has been reported that it can improve the repeatability and accuracy of capsulorhexis via projecting a pre-set size ring to guide capsulorhexis. However, we found that for the patients with corneal geriatric ring, pterygium or limbal lesions leading to unclear limbal boundary, the projected capsulorhexis will deviate from the center, resulting in capsulorhexis is off center in clinical practice. Our self-developed intraocular caliper, which is modified on the conventional intraocular irrigation needle, can accurately measure the size of capsulorhexis, and mark the position and boundary of capsulorhexis on the lens anterior capsule to guide capsulorhexis, thus significantly improves the accuracy and centricity of capsulorhexis.

The purpose of this study is to compare the centricity and accuracy of intraocular caliper-assisted capsulorhexis in phacoemulsification for age-related cataract patients with corneal limbus opacity with that of Verion projection navigation system.

• Study Type: Interventional
• Enrollment (Anticipated): 74
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Guangzhou, China, 510060
    • Zhongshan Ophthalmic Center, Sun Yat-sen University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 55 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Adults aged 55 to 80 years with age-related cataract with pterygium, Corneal geriatric ring, and corneal limbus opacity;
• Pupil diameter ≥ 6.5mm after pupil dilation;
• Lens nuclear opacity grading score (LOCS III) lower than 4.0.

Exclusion Criteria:

• Patients had previous intraocular surgery;
• Patients with a diagnosed eye disease that may affect the functions of lens suspensory ligament such as previous ocular trauma, lens subluxation, pseudoexfoliation syndrome, retinal pigment degeneration;
• Patients had other ocular diseases that impair visual function include optic neuropathy, uveitis, and tumor.
• Refused to participate the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: OTHER
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: DOUBLE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Intraocular caliper-assisted capsulotomy group; In intraocular caliper-assisted capsulotomy group, a modified intraocular caliper with standard calibration on the rinse needle was used to measure and locate the position of capsulorhexis with 5.3 mm diameter and the principle of pupillary margin in concentric circles. The surgeon could gently use the blunt needle in the front of the intraocular caliper to further make corresponding markers on the lens anterior capsule, and then carry out capsulotomy according to the marks.	Procedure: Intraocular caliper-assisted capsulotomy; Intraocular caliper is a modified intraocular caliper with standard calibration on the rinse needle.
ACTIVE_COMPARATOR: Verion navigation system-assisted capsulotomy group; In the Verion-assisted capsulotomy group, Verion navigation system was applied to project a 5.3 mm capsulorhexis centered on the corneal vertex. According to the projected capsulorhexis, capsulotomy was performed.	Procedure: Verion navigation system-assisted capsulotomy; Verion Image Guided System (Alcon Laboratories, Inc.) is a digital image guidance system consisting of a diagnostic reference unit and a surgery pilot for intraoperative surgical assistance. The device can be used to align toric intraocular lens during surgery as well as support manual creation of a capsulorhexis with a predefined target diameter.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Distance between pupil center and capsulorhexis center	The primary outcome was the distance between pupil center and capsulorhexis center. Clear images of the edges of IOL and capsulorhexis were taken at the end of the operation, and Image J image analysis software is used to measure the distance between pupil center and capsulorhexis center with the diameter of IOL optical surface (6 mm) as the reference by two independently professional graders at the meantime.	During the surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Horizontal and vertical diameter of capsulorhexis	Measured by Image J image analysis software.	During the surgery
Intraocular lens tilt	Measured by anterior segment OCT (CASIA2).	One month after surgery
Intraocular lens decentration	Measured by anterior segment OCT (CASIA2).	One month after surgery
Intraocular aberrations	Measured by OPD-SCAN III.	One month after surgery
Uncorrected and corrected visual acuity	Evaluated with ETDRS visual acuity chart.	One month after surgery
Ideal ratio of capsulorhexis	Ideal capsulorhexis is defined as a centered and round capsulorhexis , which can cover the edge of IOL optical surface continuously for 360 degrees with a diameter between 5.0 to 5.5 mm.	During the surgery
Grades of capsulorhexis-IOL overlap	The capsulorhexis-IOL overlap of each patient was graded as 360-degree continuous overlap, 270~360-degree overlap, 180~270-degree overlap, 90~180-degree overlap, and < 90-degree overlap.	During the surgery
Deviation of horizontal and vertical diameter of capsulorhexis from the target diameter (5.3 mm)	Measured by Image J image analysis software.	During the surgery
Distance between pupil center and capsulorhexis center		One month after surgery

Collaborators and Investigators

• Sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University

Study record dates

Study Major Dates

• Study Start (ANTICIPATED): August 1, 2021
• Primary Completion (ANTICIPATED): July 31, 2022
• Study Completion (ANTICIPATED): October 31, 2022

Study Registration Dates

• First Submitted: July 16, 2021
• First Submitted That Met QC Criteria: July 20, 2021
• First Posted (ACTUAL): July 26, 2021

Study Record Updates

• Last Update Posted (ACTUAL): July 26, 2021
• Last Update Submitted That Met QC Criteria: July 20, 2021
• Last Verified: July 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Cataract
• Other Study ID Numbers: 2021KYPJ111

Drug and device information, study documents

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