Diffusion‐weighted imaging helps differentiate multiple sclerosis and neuromyelitis optica‐related acute optic neuritis

Abstract

3 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1780-1785.

Apparent Diffusion Coefficient Variabilities of the Optic Nerve in Multiple Sclerosis: Optic nerve head and Intraorbital segment

“…Diffusion-weighted imaging (DWI) is a kind of MRI techniques. This technique is sensitive to the movement of water molecules (13).…”

“…By drawing the region of interest (ROI), it is possible to calculate the ADC values of different tissues on the map (14,15). DWI measurements can measure the amount of diffusion in the optic nerve, evaluate damage to axons, and predict visual results (13,(16)(17)(18). There are many studies evaluating the optic nerve DWI on MS and optic neuritis (7-9, 12, 13, 16, 19-23).…”

Diffusion-weighted imaging hyperintensity and low apparent diffusion coefficient of the optic nerve in myelin oligodendrocyte glycoprotein–IgG optic neuritis

“…4À7 DWI abnormalities and corresponding ADC values may have prognostic implications, as a lower ADC value during acute optic neuritis was associated with worse visual outcomes and more severe thinning of the retinal nerve fibre layer and macular ganglion cell complex 6 months after initial presentation. 5 ADC values may also vary with the chronicity of disease with more chronic cases having higher values. 7 DWI hyperintensities and postcontrast enhancement exhibit similar localizations within inflamed optic nerves, 4 suggesting that DWI may be an appropriate alternative for identifying acute optic neuritis when MRI with contrast is contraindicated.…”

“…4 The presence of postcontrast enhancement of the optic chiasm and lower ADC values were found to be the most important imaging characteristics for differentiating between NMOSD and optic neuritis caused by multiple sclerosis. 5,9 When applied as diagnostic criteria for NMOSD, the presence of low ADC values or optic chiasm involvement had a specificity of 78.1%, sensitivity of 77.8%, and diagnostic accuracy of 77.9%. 9 The ADC value was still low 4 weeks after symptom onset in our patient, and this was similar to a previous case of AQP4-optic neuritis, which was presumably due to lasting depletion of water channels.…”

“…It also highlights the possibility that DWI hyperintensity and low ADC signal of the optic nerve may indicate poor visual prognosis in MOG-IgG optic neuritis as suggested in AQP4-IgG optic neuritis. 5 Further studies are required to characterize the DWI abnormalities seen in MOG-IgG optic neuritis and evaluate the diagnostic and prognostic capabilities of this imaging modality.…”