Long-term optic nerve head microvascular impairment after acute primary angle closure: an OCTA study

Area of Science:

• Ophthalmology
• Microvascular Imaging
• Glaucoma Research

Background:

• Acute primary angle closure (APAC) can cause transient vision loss.
• Previous studies noted temporary decreases in fundus vessel density (VD) post-APAC.
• The long-term impact of APAC on optic nerve head (ONH) and macular microvasculature remains less understood.

Purpose of the Study:

• To investigate long-term microvascular changes, specifically vessel density (VD), in the optic nerve head (ONH) and macula after acute primary angle closure (APAC).
• To identify specific anatomical regions exhibiting reduced VD long after APAC resolution.

Main Methods:

• Quantitative microvascular assessment using spectral domain optical coherence tomography angiography (OCTA).
• Inclusion of resolved APAC eyes, primary angle closure suspects (PACS), and healthy controls.
• Analysis of peripapillary VD as the primary endpoint, with sectoral ONH VD and macular VD as secondary measures.

Main Results:

• Eyes with a history of APAC showed significantly lower peripapillary VD compared to PACS and control groups.
• The interval between APAC onset and examination ranged from 1 to 60 months (median 15 months).
• Macular VD was less affected by prior APAC, while ONH VD correlated with structural parameters.

Conclusions:

• Peripapillary vessel density remains significantly reduced in eyes with a history of APAC, even after clinical resolution.
• These findings highlight persistent microvascular alterations in the optic nerve head region following APAC.
• Long-term monitoring of microvascular changes may be relevant for managing eyes with a history of angle closure.