Longitudinal Analysis of Bruch Membrane Opening Morphometry in Myopic Glaucoma

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• The Bruch membrane opening (BMO) is a critical structure at the optic nerve head.
• Understanding longitudinal changes in BMO morphology is crucial for glaucoma diagnosis and progression monitoring.

Purpose of the Study:

• To investigate longitudinal changes in the morphologic characteristics of the BMO in control and glaucomatous subjects.
• To assess changes in BMO area, ellipse ratio, nonplanarity, and depth over time.

Main Methods:

• 53 myopic eyes (17 control, 6 suspect, 20 stable glaucoma, 10 progressing glaucoma) were imaged using swept-source optical coherence tomography over an average of 4.2 years.
• Bruch membrane (BM) and BMO were segmented, and four morphometric BMO parameters were measured at baseline and two follow-up visits.
• Longitudinal changes were analyzed using linear mixed-model and ANCOVA analyses.

Main Results:

• BMO nonplanarity increased significantly in stable and progressing glaucoma groups.
• BMO depth relative to BM increased in control, stable glaucoma, and progressing glaucoma groups.
• Axial length was associated with BMO area and nonplanarity in specific groups, but not a significant factor for the slopes of BMO parameters.

Conclusions:

• The BMO exhibits increased nonplanarity in glaucoma eyes longitudinally.
• The axial position of the BMO shifts posteriorly relative to the BM in both control and glaucoma eyes over time.
• These findings suggest dynamic structural changes at the optic nerve head relevant to glaucoma pathogenesis.