The Effectiveness of YAG Iridotomy in Preventing Peripheral Anterior Synechia After CLASS in Primary Open Angle Glaucoma

Study Overview
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Brief Summary
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To investigate the effectiveness of YAG laser iridotomy in preventing peripheral anterior synechia after CO2 Laser-Assisted Sclerectomy Surgery and the long-term effect of reducing intraocular pressure

Detailed Description
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Group A: YAG laser iridotomy was performed one week before operation, followed by CO2 Laser-Assisted Sclerectomy Surgery; Group B: only CO2 Laser-Assisted Sclerectomy Surgery; The patients were followed up for 1 year to observe and compare the difference of the incidence of peripheral anterior synechia and the effect of long-term intraocular pressure control between the two groups.

Official Title
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Effectiveness of YAG Laser Iridotomy in Preventing Peripheral Anterior Synechia After CO2 Laser-Assisted Sclerectomy Surgery in Primary Open Angle Glaucoma

Conditions
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Glaucoma, Open-angle

Intervention / Treatment
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* Device: YAG iridotomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary open angle glaucoma patients in Ophthalmic Center; Topical use of hypotensive drugs in the treatment of poor or intolerable intraocular pressure control; The patients were 18 to 50 years old, regardless of gender; Class operation was performed; Patients are able and willing to comply with the research guidance and may complete all visits required by the research; Informed consent has been signed. Exclusion Criteria: Allergic to any perioperative medication in this study; History of ocular trauma; Any previous intraocular surgery; Gonioscopy showed a narrow angle (Schaffer III or below); Secondary glaucoma was diagnosed; Optic atrophy caused by other reasons; Severe complications such as rupture of posterior capsule and choroidal hemorrhage occurred during operation; Patients with severe ocular complications after operation The patient's history indicated that he had severe dysfunction of heart, lung, liver and kidney; Women in pregnancy, lactation or planned pregnancy; The researchers believe that the patient's condition may put the patient at significant risk, may confuse the results of the study, or may significantly interfere with the patient's participation in the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: YAG iridotomy+CLASS<br>YAG iridotomy was performed one week before operation, and then CO2 Laser-Assisted Sclerectomy Surgery was performed | Device: YAG iridotomy<br>* YAG iridotomy was performed one week before operation, and then CO2 Laser-Assisted Sclerectomy Surgery was performed<br>|
| No Intervention: CLASS<br>CO2 Laser-Assisted Sclerectomy Surgery only | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraocular pressure | Intraocular pressure | 1 year | 
| Peripheral anterior synechia | Incidence of peripheral anterior synechia | 1 year |