Neuro-Ophthalmology Imaging Review Urges Smarter, Targeted Test Selection

Multimodal imaging, the deliberate pairing of tests that capture structural, functional, and vascular information, has become central to neuro-ophthalmology. But ordering tests indiscriminately can be costly and may increase incidental findings, according to a review published in the Indian Journal of Ophthalmology.¹

Lesions anywhere along the visual pathway leave measurable traces at the optic nerve head and retina. The eye offers an accessible view to the central nervous system. Researchers from Aravind Eye Hospital in India evaluated more than a dozen ocular and neuroimaging tools by their underlying principle, clinical use, comparative utility, and limitations, then proposed a syndrome-based scheme for escalating to neuroimaging.

“Understanding which test is most appropriate in a given clinical scenario is crucial for maximizing their value,” the authors wrote.

OCT and Retinal Imaging Patterns in Optic Neuritis, MS, and MOGAD

Fundus photography, a widely accessible tool, remains the typical entry point for testing. The authors cited one emergency department study in which 8.5% of headache presentations had abnormal fundus photographs. However, as a 2-dimensional image, it can miss early disc edema and buried drusen.

Optical coherence tomography (OCT) is the current standard for structural assessment. Its key metrics are peripapillary retinal nerve fiber layer (pRNFL) thickness, macular ganglion cell–inner plexiform layer (GCIPL) thickness, and Bruch’s membrane opening–minimum rim width. Across published series, combining the 3 measures consistently outperformed any single measure.

OCT patterns can also narrow the diagnosis. After optic neuritis, multiple sclerosis (MS) usually causes temporal-predominant thinning; those with aquaporin-4–positive neuromyelitis optica spectrum disorder more often cause severe diffuse loss; and those with myelin oligodendrocyte glycoprotein antibody–associated disease (MOGAD) show milder structural change relative to their visual deficit. OCT angiography adds a dye-free view of retinal vessels, but in Alzheimer disease, Parkinson disease, MS, and stroke, effect sizes are modest and overlap with controls, making it better suited as a research biomarker tool than a standalone diagnostic test.

Choosing Between CT, MRI, and Angiography in Neuro-Ophthalmology

Fluorescein angiography, used selectively, demonstrates leakage, which dye-free techniques cannot detect, and markedly delayed choroidal filling is the most specific imaging sign of giant cell arteritis. For neuroimaging, CT is first line in emergencies such as suspected hemorrhage, pituitary apoplexy, or orbital fracture. CT angiography is more sensitive than magnetic resonance angiography for aneurysms smaller than 3 mm and is preferred when aneurysm must be ruled out quickly in pupil-involving third-nerve palsy. MRI remains the definitive soft-tissue test for the optic nerve, chiasm, and retrochiasmal pathways, and the authors stressed that protocol choice is the biggest driver of its diagnostic yield.

In an interview with NeurologyLive^®, Elena Grebenciucova, MD, assistant professor of neurology at Northwestern University, described a common pitfall: a patient with eye pain and blurred vision has an orbital MRI with no enhancement, and optic neuritis is ruled out.²

With mild optic neuritis or MOGAD, “it really depends on the timing of the MRI,” she said, as well as on the quality of the scan. Anterior inflammation in MOGAD can look like papilledema on a dilated exam yet show little enhancement. She also advised that blurred vision persisting beyond several hours alongside a headache warrants a visual acuity check, a dilated exam, and contrast-enhanced orbital MRI rather than being attributed to migraine alone.

Limitations of Multimodal Imaging in Neuro-Ophthalmology

The article is a narrative review rather than a systematic analysis, and the authors noted that several quantitative measures, including OCT thickness values, OCT angiography metrics, and laser speckle flowgraphy readings, vary by device and are not interchangeable across platforms. And for laser speckle flowgraphy, between-patient diagnostic thresholds have not been established. Still, the authors concluded that these tools complement one another and add the most value when chosen to answer a specific clinical question.¹

References

1. Kumar M, Shah K, Saravanan VR, Chacko R, Jaju S, Shah VM. Multimodal imaging in neuro-ophthalmology. Indian J Ophthalmol. 2026;74(8):1129-1150. doi:10.4103/IJO.IJO_2130_25
2. Meglio M, Grebenciucova E, Cherayil N. Challenges in diagnosing optic neuritis in MS and MOGAD. NeurologyLive. March 30, 2025. Accessed September 29, 2026. https://www.neurologylive.com/view/challenges-diagnosing-optic-neuritis-in-ms-mogad