Prophylactic Peripheral Iridectomy Prevents Aphakic Angle-closure Glaucoma

Study Overview
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Brief Summary
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This is a retrospective, nonrandomized comparative trial with historical control to investigate the safety and efficacy of a novel progressive grasping peripheral iridectomy (PGPI) surgical method in preventing aphakic angle-closure glaucoma (AACG) following congenital cataract surgery.

Detailed Description
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Aphakic angle-closure glaucoma (AACG) following congenital cataract surgery is a common and serious complication which can be prevented by prophylactic peripheral iridectomy (PPI). However, it is difficult to perform routine PPI via scleral tunnel incision especially when the pupil is dilated. Here, the investigators designed a novel progressive grasping peripheral iridectomy (PGPI) surgical method which can ensure the accurate iridectomy position and minimize the complication. The aim of this study is to assess the safety and efficacy of the PGPI in preventing AACG following congenital cataract surgery. This is a retrospective, nonrandomized comparative trial with historical control. The congenital cataract patients performed with cataract extraction combined with PPI (PPI group) and the patients performed with cataract extraction alone and leaving the iris intact (historical control group) were enrolled and a retrospective medical chart review was conducted. The IOP, anterior chamber depth, corneal clarity, patency of peripheral iridectomy opening, and the rate of AACG, iris posterior synechia (IPS) and visual axis opacity (VAO) were compared between two groups.

Official Title
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A Novel Prophylactic Peripheral Iridectomy Prevents Aphakic Angle-closure Glaucoma After Congenital Cataract Surgery

Conditions
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Congenital Cataract, Aphakic Glaucoma

Intervention / Treatment
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* Procedure: PPI group
* Procedure: cataract extraction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients less than 2 years old; patients performed with congenital cataract surgery with or without PPI; patients with routine follow-up at ZOC. Exclusion Criteria: patients with IOP ≥21 mm Hg or with congenital glaucoma or with a family history of glaucoma; patients with keratopathy, retinopathy, ocular trauma, radiation therapy or intraocular surgery; patients associated with other congenital ocular anomalies, such as anterior segment dysgenesis, microcornea/microphthalmia, persistent fetal vasculature, lens dislocation and iridocoloboma; patients with systemic diseases, such as Down's syndrome, Lowe syndrome, Stickler syndrome, maternal rubella syndrome or trisomy 13.

Ages Eligible for Study
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Minimum Age: 2 Months
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: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Retrospective,consecutive,nonrandomized comparative trial with historical control
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: PPI group<br>cataract extraction surgery with prophylactic peripheral iridectomy | Procedure: PPI group<br>* The patients underwent cataract extraction, posterior capsulotomy, anterior vitrectomy combined with prophylactic peripheral iridectomy.<br>|
| Active Comparator: historical control group<br>cataract extraction surgery | Procedure: cataract extraction<br>* The patients underwent cataract extraction, posterior capsulotomy combined with anterior vitrectomy and leave the iris intact.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The rate of aphakic angle-closure glaucoma | Pupillary block with subsequent closure of the filtration angle is the cause of early aphakic angle-closure glaucoma (AACG), which usually happens in the early postoperative period, generally within the first 6 months. AACG presents with elevated IOP (repeatedly >25 mmHg), corneal edema, iris bombe, shallow anterior chamber, peripheral anterior synechia and angle closure. | 18-49 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The rate of iris posterior synechia | Postoperative uveal inflammation can result in iris posterior synechia (IPS), referring to the synechia between iris and capsule around pupil. IPS is graded according to the range of the synechia. Grade 0: no synechia; Grade I: <1 quadrant; Grade II: ≤2 quadrants and >1 quadrant ; Grade III: ≤3 quadrants and >2 quadrants; Grade IV: >3 quadrants. | 18-49 months | 
| The rate of visual axis opacity | visual axis opacification (VAO) refers to developing reopacification of the visual axis in the form of lens proliferation into the visual axis or pupillary membrane. | 18-49 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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congenital cataract, prophylactic peripheral iridectomy, aphakic angle-closure glaucoma, aphakic open-angle glaucoma, visual axis opacity, iris posterior synechia