Lens Extraction Combined With Goniosynechialysis Versus Trabeculectomy

Study Overview
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Brief Summary
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To compare the effectiveness of lens extraction combined with goniosynechialysis and trabeculectomy in treating advanced angle-closure glaucoma.

Detailed Description
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Advanced angle closure glaucoma (AACG) can result in severe visual function defect or even blindness with or without acute attacks. Different from open angle glaucoma (OAG), the main principle of treatment for AACG is not only to lower intraocular pressure (IOP) but also to protect the anterior chamber angle from closing. Previously, the most common and classical treatment for AACG was trabeculectomy. However, both doctors and patients are not satisfied with this surgery because of its limited success rate due to fibrosis of the filtration pathway. Besides, trabeculectomy has various complications, such as shallow anterior chamber, choroidal effusion, suprachoroidal hemorrhage, malignant glaucoma, and bleb leakage associated endophthalmitis. In addition, patients who underwent trabeculectomy will have decreased visual acuity in a couple of years due to accelerated development of cataract. Since a thickened and anterior-positioned lens could play a crucial role in the pathogenesis of AACG, cataract surgery has also been used. Accumulative evidence shows lens extraction alone is an efficient way in treating the early stage of ACG but has limited success rate in AACG. Lens extraction combined with goniosynechialysis (LEG) has been proved to be better than lens extraction alone in re-opening the anterior chamber angle for ACG patients with extensive peripheral anterior synechia and possibly have better effect than trabeculectomy as well from our preliminary data, which has not been proved yet. Thus, this investigation is designed to compare the effect of LEG and trabeculectomy in AACG patients prospectively in 3 years of follow-up. The investigators hypothesize that LEG could have better IOP control and better visual function than trabeculectomy in long term for AACG patients.

Official Title
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Effectiveness of Lens Extraction Combined With Goniosynechialysis Versus Trabeculectomy in Treating Advanced Angle-closure Glaucoma: a Randomized Controlled Trial

Conditions
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Glaucoma, Angle-Closure

Intervention / Treatment
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* Procedure: Lens extraction combined with goniosynechialysis
* Procedure: Trabeculectomy surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 40 years old to 80 years old more than 180-degree synechial closure of anterior chamber angle on gonioscopy IOP higher than 21mmHg under the use of more than two anti-glaucoma eye drops mean deviation of visual field worse than -12dB on Humphrey 24-2 phakic eyes Exclusion Criteria: Snellen visual acuity worse than 0.02 history of ocular trauma uveitis previous ocular surgeries significant conjunctival scar visible neovascular on iris or anterior chamber angle other severe eye diseases that would affect visual function significantly, such as age-related macular degeneration and pathogenic myopia.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 80 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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Lens extraction combined with goniosynechialysis group<br>One hundred and fifty-eight patients with advanced angle-closure glaucoma underwent phacoemulsification combined with goniosynechialysis. | Procedure: Lens extraction combined with goniosynechialysis<br>* The patients enrolled underwent phacoemulsification combined with goniosynechialysis surgery.<br>|
| Active Comparator: Trabeculectomy Group<br>One hundred and fifty-eight patients with advanced angle-closure glaucoma underwent trabeculectomy. | Procedure: Trabeculectomy surgery<br>* The patients enrolled underwent trabeculectomy surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure (IOP) change at one month | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at one month. | one month | 
| IOP change at three months | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at three months. | three months | 
| IOP change at six months | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at six months. | six months | 
| IOP change at one year | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at one year. | one year | 
| IOP change at two years | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at two years. | two years | 
| IOP change at three years | Change from baseline IOP after phacoemulsification combined with goniosynechialysis or trabeculectomy at three years. | three years | 
| Best corrected visual acuity at one month | Best corrected visual acuity of participants after surgery at one month | one month | 
| Best corrected visual acuity at three months | Best corrected visual acuity of participants after surgery at three months | three months | 
| Best corrected visual acuity at six months | Best corrected visual acuity of participants after surgery at six months | six months | 
| Best corrected visual acuity at one year | Best corrected visual acuity of participants after surgery at one year | one year | 
| Best corrected visual acuity at two years | Best corrected visual acuity of participants after surgery at two years | two years | 
| Best corrected visual acuity at three years | Best corrected visual acuity of participants after surgery at three years | three years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean deviation | The mean deviation value of Humphery visual filed tests before and after surgery. | one month, three months, six months, one year, two years, three years | 
| The thickness of retinal nerve fiber layer (RNFL) | The RNFL thickness measured by optical coherence topography (OCT) | one month, three months, six months, one year, two years, three years | 
| The thickness of ganglion cell complex (GCC) | The GCC thickness measured by OCT | one month, three months, six months, one year, two years, three years | 
| Number of eye drops | The number of eye drops after surgery. | one month, three months, six months, one year, two years, three years | 
| Adverse event | Adverse events of each group, such as cornea edma, ocular hypotension, hemorrhage | one month, three months, six months, one year, two years, three years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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phacoemulsification, goniosynechialysis, trabeculectomy