Parapapillary Deep-Layer Microvasculature Dropout and Visual Field Progression in Glaucoma

Area of Science:

• Ophthalmology
• Neuroscience
• Medical Imaging

Background:

• Glaucoma is a leading cause of irreversible blindness worldwide.
• Visual field (VF) progression is a key indicator of glaucoma severity and treatment efficacy.
• Optical coherence tomography angiography (OCT-A) allows for non-invasive visualization of retinal microvasculature.

Purpose of the Study:

• To investigate the association between parapapillary deep-layer microvasculature dropout, identified via OCT-A, and the progression of glaucomatous visual fields.
• To determine if microvasculature dropout is a predictive factor for visual field deterioration in primary open-angle glaucoma.

Main Methods:

• A retrospective cohort study included 138 eyes of 138 primary open-angle glaucoma patients with at least 5 prior VFs.
• Visual field progression was defined by Guided Progression Analysis or a significant visual field index (VFI) slope.
• Parapapillary deep-layer microvasculature dropout was qualitatively assessed using OCT-A.

Main Results:

• Fifty-five eyes (39.9%) showed VF progression.
• Eyes with microvasculature dropout had a significantly higher rate of VF progression (59.5%) compared to those without dropout (9.3%; P < .001).
• Dropout was significantly associated with prior VF progression, along with intraocular pressure, optic disc hemorrhage, and lamina cribrosa defects.

Conclusions:

• Parapapillary deep-layer microvasculature dropout detected by OCT-A is significantly associated with a higher rate of glaucomatous visual field progression.
• Microvasculature dropout may serve as a structural biomarker for past glaucomatous visual field damage.
• Further research is warranted to explore the role of deep-layer microvasculature damage in glaucoma pathogenesis.