Two Different Cataract Surgical Procedures to Prevent Posterior Capsule Opacification

Study Overview
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Brief Summary
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In this study, the investigators introduce a new capsule-reserved cataract surgical procedure in which anterior lens capsule is reserved and attached onto posterior lens capsule in the purpose of preventing posterior capsule opacification (PCO). A prospective randomized controlled study is reported to compare the new capsule-reserved surgical procedure with conventional one on the effectiveness to prevent posterior capsule opacification in age-related cataract patients.

Detailed Description
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A prospective, randomized controlled study of 240 eligible patients will been enrolled. Two eyes of each patient were assigned randomly to two groups respectively: Group I; anterior lens capsule is conventionally not reserved after continuous curvilinear capsulorhexis, while in Group II, anterior lens capsule is innovatively reserved and attached onto posterior lens capsule. This novel adjusted surgical procedure, featured by using the reserved anterior lens capsule to protect the peri-capsule microenvironment and prevent PCO, is conceptual different from the traditional cataract surgical procedure. Clinical examinations including posterior capsule opacification grading score, central posterior capsule thickness, central posterior capsule density, best corrected visual acuity, contrast sensitivity were carried out preoperatively and at each postoperative visit.

Official Title
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Effectiveness of Two Different Surgical Procedures to Prevent Posterior Capsule Opacification in Age-related Cataract Patients

Conditions
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Cataract, Posterior Capsule Opacification

Intervention / Treatment
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* Procedure: Anterior lens capsule was reserved


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 50 years or above Both eyes were diagnosed with age-related cataract Both eyes were planed to undergo the Phacoemulsification and IOL implantation surgery with 1 month Biocular BCVA improvement post surgery was feasible judged by the ophthalmologists. Exclusion Criteria: Other ocular diseases ACD<3CT Combined cataract surgery (trabeculoplasty, keratoplasty) Lens pseudoexfoliation syndrome combined with glaucoma or zonular abnormalities Previous intraocular surgery or trauma (laser not included) Uveitis Recent ocular infection Proliferative diabetic retinopathy Diabetes mellitus Congenital ocular abnormalities (aniridia, congenital cataract) Atrophy of iris Participants with previous clinical trials 30 days before surgery Using prostanoid eye drops Uncontrolled systematic diseases

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Capsule-reserved surgical procedure<br>In this group, the anterior lens capsule was reserved after continuous curvilinear capsulorhexis. The reserved anterior capsule was pressed flattened by the optical surface of the IOL and attached onto the posterior lens capsule. Phacoemulsification was performed with the same device and handpieces, using the same phaco chop technique as in the conventional procedure group. | Procedure: Anterior lens capsule was reserved<br>* The anterior lens capsule was reserved after continuous curvilinear capsulorhexis. The reserved anterior capsule was pressed flattened by the optical surface of the IOL and attached onto the posterior lens capsule.<br>|
| No Intervention: Conventional surgical procedure<br>In this group, the anterior lens capsule was not reserved or attached onto the posterior lens capsule. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline in posterior capsule opacification grading score | Posterior capsule opacification（PCO）was recorded by standardized slit lamp retroillumination images and analyzed using the EPCO2000 program. The severity of PCO was clinically graded from 0 (none) to 4 (severe) | post-operative day 1, post-operative week 1, post-operative month 1, post-operative month 3, | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline in central posterior capsule thickness | Central posterior capsule thickness was recorded and calculated by Pentacam HR system | post-operative day 1, post-operative week 1, post-operative month 1, post-operative month 3, post-operative month 6, post-operative year 1 | 
| Change from Baseline in central posterior capsule density | Central posterior capsule density was recorded and calculated by Pentacam HR system. | post-operative day 1, post-operative week 1, post-operative month 1, post-operative month 3, post-operative month 6, post-operative year 1 |