Study on Ex-PRESS Implantation Combined With Phacoemulsification in Primary Angle-closure Glaucoma

Study Overview
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Brief Summary
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Primary angle-closure glaucoma (PACG) is common, phacotrabeculectomy is associated with a significant risk of complications.The Ex-PRESS shunt was introduced as a modification to trabeculectomy, with the theoretical advantages of reduced complications.Our purpose is to perform a prospective study to evaluate the clinical outcomes and safety of the Ex-PRESS shunt with cataract surgery for PACG patients coexisting cataract.

Detailed Description
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The Ex-PRESS is a miniature stainless steel glaucoma device, developed as an alternative to trabeculectomy mainly for patients with primary open-angle glaucoma.It has been proved to be as effective as trabeculectomy in a series of researches. However the early postoperative complication of Ex-PRESS implantation is less frequent compared with trabeculectomy. Ex-PRESS was designed initially for open angle glaucoma, gradually some scholars used it in refractory postpenetrating keratoplasty glaucoma and in vitrectomized glaucoma,which showed that Ex-PRESS shunt implantation was an effective procedure too. We analyzed the clinical efficacy and safety of combined phacoemulsification and Ex-PRESS implantation for PACG patients with cataract. Data was recorded before surgery and postoperatively at 1 week and 1, 3, 6, 12,18,24,30,36 months，which included intraocular pressure (IOP), best corrected visual acuity (BCVA), number of medications, complications, corneal endothelial cell density and anterior segment optical coherence tomography(AS-OCT). Efficacy was assessed by IOP values and success rates. Complete success was determined by IOP between 5 and 21mmHg without medications.

Official Title
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Prospective Study on Ex-PRESS Implantation Combined With Phacoemulsification in Primary Angle-closure Glaucoma

Conditions
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Glaucoma, Angle-Closure

Intervention / Treatment
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* Procedure: Ex-PRESS and phacoemulsification


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The presence of PACG, angle peripheral anterior synechia (PAS) more than 180 degrees. An indication for glaucoma filtering surgery based on uncontrolled IOP or progressive vision field defect despite antiglaucoma medications. Mean vision field defect greater than 15dB. The presence of a clinically significant decrease of visual acuity as a result of cataract, usually BCVA less than 0.6. Exclusion Criteria: Patients unable to give informed consent. Ocular infection or inflammation in the study eye in the 3 months prior to enrollment. Intraocular surgery in the study eye in the 3 months prior to enrollment.

Ages Eligible for Study
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Minimum 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
Intervention Model: Single Group Assignment
Interventional Model Description: Prospective, interventional and monocentric study based in a university hospital setting
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Ex-PRESS and phacoemulsification<br>A treatment session of PACG coexisting cataract treated with phacoemulsification combined with P50 Ex-PRESS miniature glaucoma device (Alcon Laboratories, Fort Worth, Texas, USA). | Procedure: Ex-PRESS and phacoemulsification<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure (IOP) | In millimeters of mercury (mmHg), measured with the Goldmann applanation tonometer | 36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure (IOP) | In millimeters of mercury (mmHg), measured with the Goldmann applanation tonometer | 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months. | 
| Number of intraocular pressure lowering medications | Number of drops and oral medications used by the patient compared to baseline | 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months. | 
| Best corrected visual acuity (BCVA) | Number of lines reduction or improvement from baseline on Snellen acuity chart | 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months. | 
| Corneal endothelial cell density | Use non-contact specular microscope to count the endothelial cell density (cells/mm2) | 3 months | 
| Anterior chamber distance(ACD) | The distance from inner corneal surface to lens measured by AS-OCT | 3 months | 
| Angle opening distance(AOD500) | Angle opening distance 500um from the scleral spur measured by AS-OCT | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ex-PRESS, glaucoma, filtration surgery, phacoemulsification