Optical Coherence Tomography Angiography (OCTA) in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorder

Area of Science:

• Neuroimmunology
• Ophthalmology
• Vascular Biology

Background:

• Vascular changes are critical in neuroinflammatory diseases like multiple sclerosis (MS).
• Optical coherence tomography angiography (OCTA) offers non-invasive, depth-resolved imaging of retinal and choroidal vasculature.
• OCTA measures vascular density, providing an alternative to structural atrophy metrics for assessing retinal damage.

Purpose of the Study:

• To evaluate OCTA as a tool for quantifying retinal vascular changes in neuroinflammatory diseases.
• To explore OCTA's potential as a surrogate marker for central nervous system vascular pathology.
• To investigate the relationship between vascular changes and structural atrophy in MS and NMOSD.

Main Methods:

• Non-invasive imaging of retinal and choroidal vasculature using OCTA.
• Quantitative measurement of vascular density in the retina.
• Comparison of vascular density between patients with MS/NMOSD and healthy controls.
• Qualitative assessment of retinal microvasculature characteristics.

Main Results:

• Consistently lower retinal microvascular densities observed in MS and NMOSD patients compared to controls, even without prior optic neuritis.
• OCTA shows sensitivity to early-stage retinal damage and avoids the "floor-effect" seen in other OCT metrics for later disease stages.
• Preliminary data suggest OCTA can differentiate between neuroinflammatory disorders based on qualitative vascular features.

Conclusions:

• OCTA is a promising tool for assessing retinal vascular changes in MS and NMOSD, potentially serving as a surrogate marker for CNS vascular pathology.
• Further research into image quality and standardized analysis is needed for clinical integration of OCTA.
• Understanding the timing of vascular changes relative to atrophy may elucidate the role of hypoperfusion in neuroinflammation.