NCT07523139Recruiting
Vitreous Zonule in Primary Angle-Closure Glaucoma
A Cross-Sectional, Prospective Observational Study on the Role of the Vitreous Zonule in the Pathogenesis of Primary Angle-Closure Glaucoma
Source: ClinicalTrials.gov · Last updated 13 Apr 2026
Brief summary (registry, in English)
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.
- Status (registry)
- Recruiting
- Study type
- Observational
- Enrollment
- 440 (estimated)
- First submitted
- 5 Apr 2026
- Start date
- 1 Jan 2025
- Primary completion date
- Jun 2027
- Lead sponsor
- Peking University People's Hospital
- Diseases
- Glaucoma
- NCT number
- NCT07523139
What you commit to
- Study type: Observational
- Planned participants: 440
- From 1 Jan 2025 to the primary completion date, Jun 2027
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- 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.
Who the study is looking for
- 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.
Age in the registry: 30 years to 79 years · Sex: All · Accepts healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Peking University People's Hospital Coordinator of this site? Confirm its status | Beijing | China | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.