Reduced Apparent Diffusion Coefficient in Neuromyelitis Optica–Associated Optic Neuropathy

Abstract

Diffusion-weighted magnetic resonance imaging is a useful tool to differentiate between acute ischemic and demyelinating lesions. In ischemic optic neuropathy the diffusion of water is impaired, but in optic neuritis it usually remains normal. We describe a patient with optic neuritis and aquaporin-4 autoantibodies, in whom imaging revealed prolonged reduction of the apparent diffusion coefficient. Immune-mediated destruction of water channels apparently decreased movement of fluid through the inflamed nerve. Diffusion-weighted imaging may distinguish optic neuritis associated with aquaporin-4 antibodies from the more common form that occurs in conjunction with multiple sclerosis.

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

“…These results were consistent with previous reports showing that acute optic neuritis exhibited diffusion restriction and reduced ADC values in MS patients . Horton et al also reported NMO‐associated neuropathy with reduced ADC in the acute phase of optic neuritis . The pathophysiology of MS and NMO are different.…”

“…8,18,21 Horton et al also reported NMOassociated neuropathy with reduced ADC in the acute phase of optic neuritis. 22 The pathophysiology of MS and NMO are different. Unlike the acute demyelination of MS-ON, the infiltration and necrosis generated by AQP4 antibodies causes the axonal damage to be more severe.…”

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

“…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. 10 The clinical utility of DWI has yet to be directly explored in patients with MOG-optic neuritis. Here we report the first case of confirmed acute MOG-IgG optic neuritis resulting in DWI hyperintensity and corresponding low ADC signal of the intraorbital optic nerve with a similar localization to that of postcontrast enhancement on T1-weighted MRI.…”

Encephalomyelitis After Varicella Zoster Reactivation in an Immunocompromised Patient

“…1 Restricted diffusion can be used to help differentiate ischemic Reprints and permission: sagepub.com/journalsPermissions.nav DOI: 10.1177/1941874417709690 journals.sagepub.com/home/NHO optic neuropathy from optic neuritis, which can present similarly and also occurs in the immunocompromised. 1,[3][4][5][6]…”