RecruitingNot Applicable

Vitreous Zonule in Primary Angle-Closure Glaucoma

China440 participantsStarted 2025-01-01

Plain-language summary

This study aims to investigate the role of the vitreous zonule (VZ) in the pathogenesis of primary angle-closure glaucoma (PACG) and to explore the feasibility of three-dimensional ultrasound biomicroscopy (3D-UBM) for imaging the circumferential VZ. This prospective, observational study will enroll patients with primary angle-closure disease (PACD), including primary angle-closure suspect (PACS), primary angle-closure (PAC), and PACG, as well as healthy controls. All participants will undergo comprehensive ophthalmic examinations, including gonioscopy, biometric measurements using IOLMaster, and UBM imaging. The study consists of three main components: (1) analysis of VZ morphology, location, number of visible quadrants, and anterior segment parameters across different age groups and axial length groups in healthy individuals, with comparisons to age-matched PACD patients; (2) development and validation of a 3D-UBM imaging system using a rotational scanning approach to reconstruct the spatial structure of the VZ; and (3) characterization of VZ features, including density and morphology, in normal eyes versus PACD eyes using 3D-UBM. The primary outcomes include the presence, quadrant count, and morphological characteristics (vitreous zonule-pars plana angle and maximum distance) of the VZ, as well as anterior segment parameters such as lens vault, anterior chamber depth, trabecular-iris angle, and angle opening distance. By elucidating age-related and axial length-related changes in the VZ and establishing 3D-UBM as a novel imaging modality for the posterior zonular apparatus, this study seeks to provide new evidence for the mechanistic role of the VZ in angle-closure glaucoma and to identify potential imaging biomarkers for early diagnosis and risk stratification.

Who can participate

Age range

30 Years – 79 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: 1\. Age between 30 and 80 years, inclusive. 2. Diagnosis of primary angle-closure disease (PACS, PAC, or PACG) according to standardized gonioscopic criteria; or healthy controls with open angles. 3. Lens opacity graded \< 2 for cortical and nuclear opacities according to the Lens Opacities Classification System III (LOCS III). 4. Ability and willingness to provide written informed consent. Exclusion Criteria: 1\. Any intraocular disease affecting the anterior or posterior segment, including but not limited to corneal disease, iris abnormalities, lens disorders other than age-related cataract, vitreous disorders, uveoretinal diseases, or optic neuropathies. 2. Prior intraocular surgery or laser treatment, including cataract surgery, trabeculectomy, laser trabeculoplasty, laser peripheral iridotomy, laser iridoplasty, or vitreoretinal surgery. 3. Systemic diseases that may affect ocular examination or confound measurements, such as end-stage cardiac disease, renal disease, pulmonary disease, or advanced malignancy. 4. Inability to undergo ultrasound biomicroscopy (UBM) examination due to inability to maintain supine position or other contraindications. 5. Pregnancy or lactation. 6. Any condition that, in the opinion of the investigator, would compromise the participant's ability to comply with study procedures or affect the validity of the study results.

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Vitreous Zonule Visibility on Ultrasound Biomicroscopy

Timeframe: Baseline

Trial details

NCT IDNCT07523139

SponsorPeking University People's Hospital

Sponsor typeOTHER

Study typeOBSERVATIONAL

Primary completion2027-06

Contact for this trial

Kun Lv, M.D.

13681213130 lvkun0327@163.com

View on ClinicalTrials.gov More Primary Angle-Closure Glaucoma trials