Differentiating Compressive Optic Neuropathy from MOG Optic Neuritis

Clinical Differentiation

The American Academy of Ophthalmology notes that progressive, painless visual loss is typical for compressive optic neuropathy, though pain can occur with rapid expansion 4
The American Academy of Ophthalmology states that visual field defects correspond to anatomic compression site 4
The American Academy of Ophthalmology reports that optic disc appearance varies: normal, pale, or edematous, depending on the compression site 4
The American Academy of Neurology and the American Academy of Ophthalmology suggest that identifiable mass lesions, such as tumors or aneurysms, compressing the optic nerve are characteristic of compressive optic neuropathy 1, 4

The American College of Radiology recommends MRI of the orbits and head with contrast as the definitive imaging study to differentiate compressive optic neuropathy from MOG optic neuritis, with compressive optic neuropathy showing a mass lesion compressing the optic nerve, and MOG optic neuritis demonstrating longitudinally extensive optic nerve enhancement 1, 2, 3
The American College of Radiology notes that longitudinally extensive optic nerve lesions, with a median length of 23.1 mm, are characteristic of MOG optic neuritis 2, 3
The American College of Radiology states that perioptic gadolinium enhancement during the acute phase is specific for MOG optic neuritis 2, 3, 5

The American Academy of Neurology suggests ordering MRI orbits and head with and without contrast as the primary study to differentiate compressive optic neuropathy from MOG optic neuritis 1, 8
The American Academy of Neurology recommends assessing optic nerve length and perioptic enhancement to differentiate MOG optic neuritis from compressive optic neuropathy 2, 3, 5

The American Academy of Ophthalmology states that surgical decompression is the definitive treatment for compressive optic neuropathy when vision is threatened 4
The American Academy of Neurology suggests that high-dose intravenous methylprednisolone is the first-line acute treatment for MOG optic neuritis 6
The American Academy of Neurology recommends oral prednisone taper over weeks-to-months for MOG optic neuritis, as rapid taper can cause relapses 6, 7

The American Academy of Neurology notes that MOG optic neuritis can mimic idiopathic intracranial hypertension (IIH) with disc edema and elevated opening pressure 5
The American Academy of Neurology states that normal brain MRI does not exclude MOG optic neuritis, and in fact, increases the pre-test probability 5
The American Academy of Neurology warns that ELISA testing for MOG-IgG has poor specificity, and only cell-based assays are acceptable 6, 7, 5