Optical Microangiography and Progressive Retinal Nerve Fiber Layer Loss in Primary Angle-closure Glaucoma.

Area of Science:

• Ophthalmology
• Glaucoma Research
• Retinal Imaging Analysis

Background:

• Primary angle-closure glaucoma (PACG) is a significant cause of vision loss.
• Understanding factors predicting retinal nerve fiber layer (RNFL) loss is crucial for managing PACG.
• Optical microangiography (OMAG) offers detailed microvascular imaging, but its predictive role in PACG progression is under investigation.

Purpose of the Study:

• To investigate the association between OMAG measurements and the rate of RNFL loss in patients with mild to moderate PACG.
• To identify clinical and imaging predictors of RNFL thinning in this patient cohort.

Main Methods:

• A prospective study followed 30 PACG patients (45 eyes) for at least 2 years, with a minimum of 3 OCT examinations.
• OMAG imaging was performed at baseline to assess perfusion density.
• Linear mixed models evaluated the effect of clinical parameters (age, IOP, etc.) and baseline OMAG on the rate of RNFL change.

Main Results:

• The average rate of RNFL change was -2.5±1.7 µm/year.
• Younger patient age and higher peak intraocular pressure (IOP) during follow-up were significantly associated with a faster rate of RNFL loss.
• Baseline OMAG parameters (peripapillary and macular perfusion density) were not significantly associated with the rate of RNFL loss.

Conclusions:

• Younger age and elevated peak IOP are significant risk factors for accelerated RNFL loss in mild to moderate PACG.
• Baseline OMAG imaging may have a limited role in predicting structural progression in PACG.
• Further research is needed to explore longitudinal OMAG changes and their correlation with glaucoma progression.