Evaluation of Filtering Bleb After Glaucoma Surgery by AS-OCTA

Study Overview
=================
Brief Summary
-----------------
When antihypertensive drugs or laser therapy can not reach the target intraocular pressure, trabeculectomy (TRAB) is still the standard surgical method for glaucoma. The scarring of the operative area is a common reason for the failure of trabeculectomy. After trabeculectomy, maintaining the shape and function of the filtering bleb is an important aspect to maintain the surgical effect. The increase in the number of blood vessels on the filtering bleb and the morphological curvature are often the manifestations of decompensation of the filtering bleb. Angiogenesis in the filtering bleb region plays an important role in surgical incision healing and is related to the accompanying scar formation. Therefore, the evaluation of vascular distribution of filtering blebs is an important index and early parameter to evaluate the success or failure of surgery. With the improvement of detection methods, it is possible to use AS-OCTA to evaluate the function and prognosis of filtering bleb after trabeculectomy. Antimitotic drugs such as 5-fluorouracil (5-FU) or mitomycin C (MMC) have always been the most commonly used clinical drugs, but the side effects caused by their use are not satisfactory. It is still the research direction of glaucoma to find new targets for regulating wound healing and more safe and effective drugs.

Detailed Description
-----------------
Glaucoma is a group of optic nerve diseases characterized by progressive and irreversible degeneration of retinal ganglion cells and their axons. Retinal ganglion cells, RGCs is a kind of central nervous system neuron whose cell bodies are located in the retina and axons make up the optic nerve. When antihypertensive drugs or laser therapy can not reach the target intraocular pressure, trabeculectomy (TRAB) is still the standard surgical method for glaucoma. The scarring of the operative area is a common reason for the failure of trabeculectomy. After trabeculectomy, maintaining the shape and function of the filtering bleb is an important aspect to maintain the surgical effect. The increase in the number of blood vessels on the filtering bleb and the morphological curvature are often the manifestations of decompensation of the filtering bleb. Angiogenesis in the filtering bleb region plays an important role in surgical incision healing and is related to the accompanying scar formation. Therefore, the evaluation of vascular distribution of filtering blebs is an important index and early parameter to evaluate the success or failure of surgery. With the improvement of detection methods, it is possible to use AS-OCTA to evaluate the function and prognosis of filtering bleb after trabeculectomy. Antimitotic drugs such as 5-fluorouracil (5-FU) or mitomycin C (MMC) have always been the most commonly used clinical drugs, but the side effects caused by their use are not satisfactory. It is still the research direction of glaucoma to find new targets for regulating wound healing and more safe and effective drugs.

Official Title
-----------------
Study on the Value and Mechanism of AS-OCTA in the Evaluation of Filtering Bleb Function and Outcome After Glaucoma Surgery

Conditions
-----------------
Trabeculectomy

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Those who are over 18 years old and can complete all the tests and examinations. Patients who want to undergo trabeculectomy in accordance with the diagnosis of glaucoma. Intraocular pressure can not be controlled by intraocular pressure lowering drugs and laser therapy (intraocular pressure can not be controlled ≤ 21mmHg). Exclusion Criteria: Those with a history of ocular trauma, trabeculectomy within 6 months, eye surgery or eye laser within 3 years. The conjunctival state of the proposed surgical area can not support high-quality imaging (signal intensity < 6). Postoperative conjunctival hemorrhage or serious complications, including hyphema, malignant glaucoma, endophthalmitis and so on. The condition of the whole body does not support surgery, such as heart disease, mental illness, malignant tumor, etc. After trabeculectomy, glaucoma drug treatment or reoperation was performed. Pregnant, lactating and pregnant women. Those who refuse to sign the informed consent form or voluntarily withdraw from the study due to discomfort or other reasons.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------
What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in the results of baseline AS-OCTA at different points in time | AS-OCTA | AS-OCTA was performed before operation, 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vision | Changes of visual acuity at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| Slit lamp microscope | Changes of baseline slit lamp microscope at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| Anterior segment photography | Photographic changes of anterior segment at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| Intraocular pressure | Changes of intraocular pressure at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| Anterior chamber gonioscope | Changes of anterior chamber gonioscope at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| UBM | UBM changes at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| fundus color photography | Changes of fundus color photography at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| A ultrasound | Changes of A-ultrasound at baseline and at different times | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| B ultrasound | Changes of B-ultrasound at baseline and at different times | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 
| visual field | Changes of visual field at baseline and at different time points | The examination was performed before operation and 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks and 24 weeks after operation. | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Glaucoma, AS-OCTA, TRAB, 5-FU, MMC, Filtering bleb