Comparison of Posterior Continuous Curvilinear Capsulorhexis With or Without Anterior Vitrectomy

Study Overview
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Brief Summary
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Selecting the appropriate surgical approach for congenital cataracts presents challenging for ophthalmologists. This prospective, randomized controlled study aims to compare the prognosis of posterior continuous curvilinear capsulorhexis (PCCC) with or without anterior vitrectomy (A-Vit) in treating congenital cataracts.

Detailed Description
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Due to the particularity of children's eye structure, selecting the appropriate surgical approach for congenital cataracts presents challenging for ophthalmologists. The major concerned postoperative problem is the after-cataract formation. As a result, PCCC with A-Vit is usually performed to prevent the formation of secondary cataracts. However. Debate over the indication and surgical procedure still persists since A-Vit and excessive manipulations may interfere with the development of the eye and increase the risk of postoperative inflammation, unstable intraocular pressure, macular edema, retinal detachment and so on. Thus, it is necessary to evaluate the safety and effectiveness of PCCC without A-Vit in congenital cataract surgery. In this randomized clinical trial, children with equal degree of congenital cataract in both eyes are enrolled. Patients receive cataract surgery on both eyes on the same day. For each patient, one eye is randomly assigned to undergo PCCC+A-Vit procedure, while the fellow eye is undergoing PCCC procedure without A-Vit. PCCC+A-Vit procedure includes anterior continuous curvilinear capsulorhexis (ACCC), irrigation/aspiration (I/A), PCCC, and A-Vit. Primary intraocular lens implantation (IOL) is performed in children older than age of two. Investigators then compare the incidence of visual axis opacity, uveitis, iris/pupil abnormality and intraocular pressure between two groups.

Official Title
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Comparison of Posterior Continuous Curvilinear Capsulorhexis With or Without Anterior Vitrectomy in Congenital Cataract Surgery

Conditions
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Congenital Cataract

Intervention / Treatment
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* Procedure: PCCC procedure without A-vit
* Procedure: PCCC+A-Vit procedure


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Children with bilateral congenital cataracts without other ocular abnormalities Gestational age at birth >37 weeks No more than 18 years old Pupils could dilate normally pre-operation Have signed a consent form Can be followed Exclusion Criteria: Intraocular pressure >21 mmHg History of ocular trauma and intraocular surgery

Ages Eligible for Study
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Minimum Age: 1 Month
Maximum Age: 18 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: PCCC procedure without A-vit<br>Procedure/Surgery: PCCC procedure without A-vit ACCC + I / A + PCCC or ACCC + I / A +PCCC + IOL | Procedure: PCCC procedure without A-vit<br>* In this randomized clinical trial, patients receive cataract surgery on both eyes on the same day. For each patient, one eye is randomly assigned to undergo PCCC+A-Vit procedure, while the fellow eye is undergoing PCCC procedure without A-Vit.<br>|
| Active Comparator: PCCC+A-Vit procedure<br>Procedure/Surgery: PCCC+A-Vit procedure ACCC + I / A + PCCC + A-vit or ACCC + I / A +PCCC + IOL + A-vit | Procedure: PCCC+A-Vit procedure<br>* PCCC+A-Vit procedure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with visual axis opacification | Number of participants with visual axis opacification evaluated based on the retro-illumination. | 5 years | 
| Number of participants with uveitis and iris/pupil abnormality | Number of participants with uveitis and iris/pupil abnormality evaluated based on the slip lamp examination. | 5 years | 
| IOP | Intraocular pressure measured by the Tono-pen or non-contact tonometer | 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BCVA change | Change from baseline in the best corrected visual acuity (BCVA) measured by the Teller's acuity card, the Lea symbol visual acuity chart or the ETDRS chart according the patient's age. | 5 years | 
| AL change | Change from baseline in axial length measured by AL-Scan, IOLMaster or A-scan | 5 years | 
| CCT change | Change from baseline in the central corneal thickness (CCT) measured by pentacam. | 5 years | 
| CFT change | Change from baseline in the central foveal thickness (CFT) measured by Optical Coherence Tomography (OCT) | 5 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Congenital cataract surgery, anterior vitrectomy, postoperative complications