Morphological-Gene-Clinical Phenotype Correlation Study of the Long Anterior Zonule

A Morphological, Genetic, and Clinical Phenotype Association Study of the Long Anterior Zonule (LAZ) Based on Multimodal Imaging and Genetic Testing

Long anterior zonules (LAZ) is an anatomical anomaly of the anterior segment in which zonular fibers extend abnormally forward onto the anterior lens capsule. It is potentially associated with glaucoma, late-onset retinal degeneration, and increased risks during cataract surgery. This study introduces a 3D visualization system to enhance the detection rate of LAZ. By integrating multiple imaging modalities, it systematically assesses the morphological characteristics of LAZ, aiming to provide an evidence-based foundation for subsequent efforts to establish diagnostic consensus, optimize preoperative assessments for glaucoma and cataract surgery. By elucidating the genetic mechanisms and genotype-phenotype correlations of LAZ, this research can provide theoretical support for the early identification of high-risk populations, genetic consultation, and personalized treatment.

Study Overview

• Status: Enrolling by invitation
• Conditions: Long Anterior Zonules
• Intervention / Treatment: Genetic: Control; Genetic: Long anterior zonules; Genetic: LAZ Pedigree

• Study Type: Observational
• Enrollment (Estimated): 600

Contacts and Locations

Study Locations

• China
  • Fujian
    • Fuzhou, Fujian, China, 350007
      • Fuzhou Eye Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

LAZ (Long anterior zonules) is characterized by the abnormal anterior extension of the ciliary zonule fibers, resulting in a significant reduction in the diameter of the central zonule-free zone of the lens.

Description

Inclusion Criteria:

• Control Group Routine cataract patient, no signs of LAZ, intraocular pressure ≤21 mmHg, and no history of glaucoma, pigment dispersion syndrome, or other eye diseases that clearly affect the anterior segment structure.
• LAZ Group Patients with cataracts combined with LAZ were independently evaluated by at least two senior ophthalmologists under slit-lamp examination or a 3D visualization system, and were required to meet the predefined diagnostic criteria for LAZ.
• LAZ Pedigree Cohort First-degree and above relatives of the LAZ proband, aged ≥18 years, regardless of the presence or absence of LAZ or related ocular disease phenotypes.

Exclusion Criteria:

• Secondary glaucoma with a clear etiology (such as inflammatory, traumatic, or neovascular glaucoma, etc.)
• History of previous intraocular surgery (e.g., cataract, glaucoma, or vitreoretinal surgery), with refractive surgery history documented but analyzed with caution
• Presence of ocular conditions affecting anterior segment imaging quality, such as corneal leukoma or severe cataract
• Individuals with severe systemic diseases (e.g., poorly controlled diabetes, connective tissue diseases) or mental disorders that hinder cooperation during examinations
• Pregnant or lactating women.

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Control Group	Genetic: Control; Routine cataract patient, no signs of LAZ, intraocular pressure ≤21 mmHg, and no history of glaucoma, pigment dispersion syndrome, or other eye diseases that clearly affect the anterior segment structure.
LAZ Group	Genetic: Long anterior zonules; Patients with cataracts combined with LAZ were independently evaluated by at least two senior ophthalmologists under slit-lamp examination or a 3D visualization system, and were required to meet the predefined diagnostic criteria for LAZ.
LAZ Pedigree Cohort	Genetic: LAZ Pedigree; First-degree and above relatives of the LAZ proband, aged ≥18 years, regardless of the presence or absence of LAZ or related ocular disease phenotypes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Axial length	Axial length, anterior chamber depth, lens thickness, corneal curvature, corneal diameter	1 day pre-op
Anterior chamber depth		1 day pre-op
Lens thickness		1 day pre-op
Corneal curvature		1 day pre-op
Corneal diameter (WTW)		1 day pre-op
Imaging of LAZ morphology and distribution	The images and videos about slit lamp and 3D visualization system.	1 day pre-op
Gene sequencing	Identification of pathogenic genes	through study completion, an average of 1 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Uncorrected Visual Acuity (UCVA)		1 day pre-op; 1 day post-op; 7 days post-op; 30 days post-op
Corrected Distance Visual Acuity (CDVA)		1 day pre-op; 1 day post-op; 7 days post-op; 30 days post-op
Spherical equivalent (SE)		1 day pre-op; 1 day post-op; 7 days post-op; 30 days post-op
Intraocular pressure		1 day pre-op; 1 day post-op; 7 days post-op; 30 days post-op
Intraoperative complications	Intraoperative capsular complications occur	Intraoperative
Age		1 day pre-op
Sex		1 day pre-op
Diagnosis	Diagnosis of accompanying ocular and systemic conditions, such as glaucoma, macular degeneration, hypertension, diabetes, etc.	1 day pre-op
Anterior chamber volume (ACV)		1 day pre-op
Anterior chamber area (ACA)		1 day pre-op
Angle opening distance (AOD)		1 day pre-op
Trabecular iris angle (TIA)		1 day pre-op
Images of the ciliary body structure	Images of the ciliary body captured by UBM	1 day pre-op

Collaborators and Investigators

• Sponsor: Fuzhou Eye Hospital

Study record dates

Study Major Dates

• Study Start (Actual): January 10, 2025
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: April 9, 2026
• First Submitted That Met QC Criteria: April 17, 2026
• First Posted (Actual): April 24, 2026

Study Record Updates

• Last Update Posted (Actual): April 24, 2026
• Last Update Submitted That Met QC Criteria: April 17, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: FZYKYY-KY-2025-005

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