Peripapillary Retinal Nerve Fiber Layer Vascular Microcirculation in Glaucoma Using Optical Coherence...

Area of Science:

• Ophthalmology
• Medical Imaging
• Glaucoma Research

Background:

• Glaucoma is a leading cause of irreversible blindness.
• Early detection and monitoring of glaucoma progression are crucial.
• Vascular changes in the optic nerve head and retinal nerve fiber layer (RNFL) are implicated in glaucoma pathogenesis.

Purpose of the Study:

• To investigate changes in retinal nerve fiber layer (RNFL) vascular microcirculation.
• To compare microcirculation between normal, glaucoma suspect, and open-angle glaucoma (OAG) groups.
• To assess the utility of optical coherence tomography-based microangiography (OMAG) in glaucoma evaluation.

Main Methods:

• Utilized a Cirrus HD-OCT 5000-based OMAG prototype system to scan the optic nerve head (ONH).
• Extracted blood flow signals using OMAG algorithm to measure RNFL vascular microcirculation (blood flux index, vessel area density).
• Analyzed microcirculation differences among groups and correlated with clinical parameters using statistical models.

Main Results:

• OAG and glaucoma suspect eyes exhibited significantly lower blood flux index compared to normal eyes (P ≤ 0.0015).
• RNFL blood flow metrics correlated significantly with visual field indices and structural changes in glaucomatous eyes (P ≤ 0.0123).
• Blood flux index demonstrated similar discrimination capability to RNFL thickness in identifying glaucoma.

Conclusions:

• Peripapillary RNFL vascular microcirculation, measured by OMAG's blood flux index, differs significantly across OAG, glaucoma suspect, and normal groups.
• RNFL microcirculation is significantly correlated with functional and structural glaucoma defects.
• OMAG-based RNFL microcirculation measurement shows promise for assisting physicians in glaucoma monitoring.