Clinical Evaluation of Intraocular Caliper-assisted Capsulotomy for Age-related Cataract

Comparison of Intraocular Caliper-assisted and Verion Navigation System-assisted Capsulotomy in Phacoemulsification Surgery: A Randomized Non-inferiority Trial

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 of patients.

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. However, most surgeons perform CCC by experience or referring to the pupil size, which is highly subjective and the accuracy of capsulorhexis is unsatisfactory. The investigators developed a new modified intraocular caliper with standard calibration on the rinse needle, which can measure and locate the position of capsulorhexis. The surgeon can 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. We found intraocular caliper-assisted capsulotomy can obviously improve the accuracy of capsulorhexis. The purpose of this study is to compare the accuracy and postoperative visual quality of intraocular caliper-assisted capsulotomy with those of digital image projection device VERION navigation system.

• Study Type: Interventional
• Enrollment (Anticipated): 156
• 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;
• 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 Assignment
• 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
Deviation of horizontal and vertical diameter of capsulorhexis from the target diameter (5.3 mm)	Images of the edges of IOL and capsulorhexis are taken at the end of the operation. Image J image analysis software is used to measure the horizontal diameter and vertical diameter of capsulorhexis with the diameter of IOL optical surface (6 mm) as the reference by two independently professional graders at the meantime, and further calculate the deviation of horizontal and vertical diameter of capsulorhexis from the target diameter (5.3 mm) .	During the surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Uncorrected and corrected visual acuity	Visual acuity is 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 is 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
Distance between pupil center and capsulorhexis center	Measured by Image J image analysis software.	During the surgery
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
Deviation of horizontal and vertical diameter of capsulorhexis from the target diameter (5.3 mm)		One month after surgery

Collaborators and Investigators

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

Study record dates

Study Major Dates

• Study Start (Anticipated): July 26, 2021
• Primary Completion (Anticipated): February 28, 2022
• Study Completion (Anticipated): April 30, 2022

Study Registration Dates

• First Submitted: July 15, 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: 2021KYPJ110

Drug and device information, study documents

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