Clinical Evaluation of Modified 2.2mm Microincision Phacoemulsification for Age-related Cataract

This study is a single-center, parallel-group, randomized controlled trial with the following objectives: to compare the incidence of post-operative descemet membrane detachment (DMD) in phacoemulsification surgery between modified and conventional 2.2mm microincision.

Study Overview

• Status: Completed
• Conditions: Cataract
• Intervention / Treatment: Procedure: modified 2.2mm microincision; Procedure: conventional 2.2mm microincision

Detailed Description

2.2mm incision is considered an ideal incision size in phacoemulsification. However, DMD is a common and serious complication in 2.2mm microincision phacoemulsification for hard nucleus age-related cataract. DMD is originated from the incision in the operation. How to construct the appropriate incision shape and size for reducing the occurrence of DMD is an important problem to be solved urgently in phacoemulsification surgery.

The investigators found that enlarging the internal incision could increase the range of motion of surgical instruments and reduce the friction of instruments to incision. Therefore，the incidence of DMD would be reduced. The investigators developed this technique, modified 2.2mm incision, to reduce the incidence of incision-site DMD and not to increase other incision related complications.

In this trial, the investigators aim to compare modified and conventional 2.2mm incision with regard to safety and efficacy in reducing the incidence of DMD.

• Study Type: Interventional
• Enrollment (Actual): 130
• 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: 65 years to 90 years (OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged-related cataract patients between 65 and 90 years ;
• Lens nuclear opalescence grade ≥4.0 on the Lens Opacities Classification System III (LOCS III);
• Scheduled for phacoemulsification combined with intraocular lens implantation.
• The number of corneal endothelial cells > 1500cells/mm2.
• Dilated pupil diameter ≥6mm

Exclusion Criteria:

• A history of ophthalmic trauma or surgery;
• Other ophthalmic diseases such as glaucoma, uveitis, high myopia;
• Ocular factors that would make surgery challenging or dangerous, including but not limited to small pupil, shallow anterior chamber, etc.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: modified 2.2mm micoincision	Procedure: modified 2.2mm microincision; enlarging the internal incision about 0.4mm for conventional 2.2mm coaxial microincision phacoemulsification
ACTIVE_COMPARATOR: conventional 2.2mm microincision	Procedure: conventional 2.2mm microincision; conventional 2.2mm coaxial microincision phacoemulsification

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of DMD at postoperative day 1	Incidence of incision-site descemet membrane detachment observed by anterior segment OCT at postoperative day 1	postoperative day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
maximal incision thickness	maximal incision thickness measured by anterior segment OCT at postoperative day 1, day 7, month 1, month 3	postoperative day 1, day 7, month 1, month 3
surgical induced-astigmatism	surgical induced-astigmatism was calculated at each postoperative visit using the following equation: K2 = [K1 2 + K32 -2 K1 K3 cos (2θ3 -2θ1)]1/2	postoperative day 1, day 7, month 1, month 3
the length of DMD	the length of incision-site descemet membrane detachment measured by anterior segment OCT at postoperative day 1, day 7, month 1, month 3	postoperative day 1, day 7, month 1, month 3
Best corrected visual acuity (BCVA)	Best corrected visual acuity (BCVA) is evaluated with an ETDRS chart at each postoperative visit	postoperative day 1, day 7, month 1, month 3
modulation transfer function (MTF)-cut off	modulation transfer function (MTF)-cut off measured by itrace at each postoperative visit	postoperative day 1, day 7, month 1, month 3
central cornea endothelial cell loss	Central cornea endothelial cell loss was calculated on the basis of preoperative and postoperative endothelial cell density.	postoperative day 1, day 7, month 1, month 3

Collaborators and Investigators

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

Publications and helpful links

General Publications

• Dai Y, Liu Z, Wang W, Han X, Jin L, Chen X, Jin G, Wang L, Zhang E, Qu B, Liu J, Congdon N, He M, Luo L, Liu Y. Incidence of Incision-Related Descemet Membrane Detachment Using Phacoemulsification With Trapezoid vs Conventional 2.2-mm Clear Corneal Incision: A Randomized Clinical Trial. JAMA Ophthalmol. 2021 Nov 1;139(11):1228-1234. doi: 10.1001/jamaophthalmol.2021.4148.

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 22, 2019
• Primary Completion (ACTUAL): October 22, 2019
• Study Completion (ACTUAL): January 22, 2020

Study Registration Dates

• First Submitted: July 6, 2019
• First Submitted That Met QC Criteria: July 8, 2019
• First Posted (ACTUAL): July 10, 2019

Study Record Updates

• Last Update Posted (ACTUAL): September 16, 2020
• Last Update Submitted That Met QC Criteria: September 13, 2020
• Last Verified: September 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Cataract
• Other Study ID Numbers: 2019KYPJ091

Drug and device information, study documents

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