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

Cataract Extraction Clinical Trial

Official title:

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

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT04977102
• Other study ID #: 2021KYPJ111
• Status: Not yet recruiting
• Phase: N/A
• Start date: August 1, 2021
• Est. completion date: October 31, 2022

Study information

• Verified date: July 2021
• Source: Zhongshan Ophthalmic Center, Sun Yat-sen University
• Contact: Xiaoyun Chen, PhD
• Phone: +86 13632343642
• Email: chenxiaoyun[@]gzzoc.com
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

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.

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.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 74
• Est. completion date: October 31, 2022
• Est. primary completion date: July 31, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 55 Years to 80 Years

Eligibility

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.

Related Conditions & MeSH terms

• Cataract
• Cataract Extraction

Intervention

Procedure:
• Intraocular caliper-assisted capsulotomy
Intraocular caliper is a modified intraocular caliper with standard calibration on the rinse needle.
• 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.

Locations

Country	Name	City	State
China	Zhongshan Ophthalmic Center, Sun Yat-sen University	Guangzhou

Sponsors (1)

Lead Sponsor	Collaborator
Zhongshan Ophthalmic Center, Sun Yat-sen University

Country where clinical trial is conducted

China, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	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	Uncorrected and corrected visual acuity	Evaluated with ETDRS visual acuity chart.	One month after surgery
Secondary	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
Secondary	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
Secondary	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
Secondary	Horizontal and vertical diameter of capsulorhexis	Measured by Image J image analysis software.	During the surgery
Secondary	Intraocular lens tilt	Measured by anterior segment OCT (CASIA2).	One month after surgery
Secondary	Intraocular lens decentration	Measured by anterior segment OCT (CASIA2).	One month after surgery
Secondary	Intraocular aberrations	Measured by OPD-SCAN III.	One month after surgery
Secondary	Distance between pupil center and capsulorhexis center		One month after surgery