Evaluation of Filtering Bleb After Glaucoma Surgery by AS-OCTA (AS-OCTA)

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

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.

Study Overview

• Status: Unknown
• Conditions: Trabeculectomy

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.

• Study Type: Observational
• Enrollment (Anticipated): 50

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Patients preparing for trabeculectomy for glaucoma

Description

Inclusion Criteria:

1. Those who are over 18 years old and can complete all the tests and examinations.
2. Patients who want to undergo trabeculectomy in accordance with the diagnosis of glaucoma.
3. Intraocular pressure can not be controlled by intraocular pressure lowering drugs and laser therapy (intraocular pressure can not be controlled ≤ 21mmHg).

Exclusion Criteria:

1. Those with a history of ocular trauma, trabeculectomy within 6 months, eye surgery or eye laser within 3 years.
2. The conjunctival state of the proposed surgical area can not support high-quality imaging (signal intensity < 6).
3. Postoperative conjunctival hemorrhage or serious complications, including hyphema, malignant glaucoma, endophthalmitis and so on.
4. The condition of the whole body does not support surgery, such as heart disease, mental illness, malignant tumor, etc.
5. After trabeculectomy, glaucoma drug treatment or reoperation was performed.
6. 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.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

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.

Collaborators and Investigators

• Sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University

Publications and helpful links

General Publications

• Weinreb RN, Khaw PT. Primary open-angle glaucoma. Lancet. 2004 May 22;363(9422):1711-20. doi: 10.1016/S0140-6736(04)16257-0.
• Yamazaki M, Omodaka K, Takahashi H, Nakazawa T. Estimated retinal ganglion cell counts for assessing a wide range of glaucoma stages, from preperimetric to advanced. Clin Exp Ophthalmol. 2017 Apr;45(3):310-313. doi: 10.1111/ceo.12852. Epub 2016 Nov 13. No abstract available.

Helpful Links

• Primary open-angle glaucoma
• Estimated retinal ganglion cell counts for assessing a wide range of glaucoma stages, from preperimetric to advanced

Study record dates

Study Major Dates

• Study Start (Anticipated): September 1, 2020
• Primary Completion (Anticipated): August 30, 2021
• Study Completion (Anticipated): August 30, 2021

Study Registration Dates

• First Submitted: August 5, 2020
• First Submitted That Met QC Criteria: August 12, 2020
• First Posted (Actual): August 17, 2020

Study Record Updates

• Last Update Posted (Actual): August 17, 2020
• Last Update Submitted That Met QC Criteria: August 12, 2020
• Last Verified: August 1, 2020

More Information

Terms related to this study

• Keywords: Glaucoma; 5-FU; AS-OCTA; TRAB; MMC; Filtering bleb
• Additional Relevant MeSH Terms: Eye Diseases; Ocular Hypertension; Glaucoma
• Other Study ID Numbers: 2020KYPJ119

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No