Zonular instability-associated morphologic features in eyes with primary angle closure disease using the swept-source...

Area of Science:

• Ophthalmology
• Anatomic Pathology
• Medical Imaging

Background:

• Primary Angle Closure Disease (PACD) is a significant cause of vision impairment.
• Zonular instability complicates cataract surgery in PACD patients.
• Understanding lens morphology in PACD is crucial for surgical outcomes.

Purpose of the Study:

• To investigate the morphologic features of the crystalline lens in PACD patients with zonular instability.
• To compare lens parameters between PACD eyes with and without zonular instability, and with cataract controls.
• To identify risk factors associated with zonular instability in PACD.

Main Methods:

• Utilized swept-source CASIA 2 Anterior Segment-Optical Coherence Tomography (AS-OCT).
• Enrolled 398 eyes from 398 patients (125 PACD with instability, 133 PACD with stability, 140 controls).
• Performed logistic regression analysis to identify risk factors.

Main Results:

• PACD eyes showed anterior lens equator, steeper anterior curvature, shorter axial length, shallower anterior chamber distance (ACD), higher lens vault (LV), and thicker lens compared to controls.
• PACD eyes with instability had steeper anterior lens curvature, thicker anterior lens part, higher anterior-to-posterior thickness ratio, shallower ACD, and greater LV than those with stability.
• Logistic regression identified positive correlations between zonular instability and anterior part thickness, anterior-to-posterior thickness ratio, and LV; negative correlations with lens anterior radius and ACD.

Conclusions:

• Steeper anterior lens curvature, increased anterior part thickness, higher anterior-to-posterior thickness ratio, shallower ACD, and greater LV are key anatomic features associated with zonular instability in PACD.
• These morphologic characteristics are important considerations for cataract surgery planning in PACD patients.
• AS-OCT provides valuable insights into lens anatomy relevant to surgical complications in PACD.