Comparison of Minimal Invasive Lens Surgery and Traditional Cataract Surgery

Study Overview
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Brief Summary
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Previously, we have developed a minimal invasive lens surgery in the purpose of reduce post-operative complications of congenital cataract. This prospective, randomized controlled study aims at comparing the prognosis of the minimal invasive lens surgery and the traditional cataract surgery for treating congenital cataracts.

Detailed Description
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Patients with congenital cataract that requires surgical intervention are enrolled. Then the patients are assigned to two groups: Group I: the participants receive a minimal invasive lens surgery, while in Group II, the participants receive a traditional cataract surgery. A secondary intraocular lens implantation is performed when the patient is two years old for both Group I and Group II. Investigators then compare the visual acuity, incidence of high intraocular pressure, incidence of visual axis opacification, uveitis and iris/pupil abnormality between two groups, to evaluate and compare the prognosis of minimal invasive lens surgery and traditional cataract surgery for treating congenital cataracts.

Official Title
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Comparison of Minimal Invasive Lens Surgery and Traditional Cataract Surgery for Treating Congenital Cataracts

Conditions
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Congenital Cataract

Intervention / Treatment
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* Procedure: minimal invasive lens surgery
* Procedure: traditional cataract surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 1 month and 24 months Uncomplicated congenital cataract (≥ 3 mm central dense opacity) in one or both eyes with an intact non-fibrotic capsular bag Informed consent signed by a parent or legal guardian Exclusion Criteria: confirmed or suspected hereditary cataract, including and not restricted to family history of congenital cataract Intraocular pressure >21 mmHg Preterm birth (<28 weeks) Presence of other ocular diseases (keratitis, keratoleukoma, aniridia, glaucoma) or systemic disease (congenital heart disease, ischemic encephalopathy) History of ocular diseases (any congenital eye diseases, such as, congenital cataract, congenital glaucoma, congenital aniridia) in the family History of ocular trauma Microcornea Persistent hyperplastic primary vitreous Rubella Lowe syndrome

Ages Eligible for Study
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Minimum Age: 1 Month
Maximum Age: 24 Months

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: traditional cataract surgery<br>Central anterior continuous capsulorhexis (5-6 mm)+ irrigation/aspiration + posterior capsulorhexis + anterior vitrectomy（ACCC+ I/A + PCCC + Anti-vit) | Procedure: traditional cataract surgery<br>* ACCC+ I/A + PCCC + Anti-vit: anterior continuous capsulorhexis + irrigation/aspiration + posterior capsulorhexis + anterior vitrectomy<br>|
| Experimental: minimal invasive lens surgery<br>Peripheral capsulorhexis opening (1.0-1.5 mm)+irrigation/aspiration | Procedure: minimal invasive lens surgery<br>* We decreased the size of the capsulorhexis opening to 1.0-1.5 mm in diameter. Then we moved the location of the capsulorhexis to the peripheral area of the lens instead of the central area. A 0.9 mm phacoemulsification probe was used to remove the lens contents and/or cortical opacities.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best correctied visual acuity | Determined with the Teller's acuity card, the Lea symbol visual acuity chart or the ETDRS chart according the patient's age. | recorded at each follow-up to five years of age. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| High intra-ocular pressure | Determined with Tono-Pen tonometer at each follow-up | after lens removal to five years of age. | 
| Visual axis opacification | Determined with slit-lamp photography at each follow-up | after lens removal to five years of age. | 
| Bi-ocular visual function | Determined with synoptophore | performed when the patient is four years old and five years old. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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congenital cataract, minimal invasive surgery, secondary intraocular lens implantation