Acute disseminated encephalomyelitis (ADEM)
Overview:
Widespread attack of inflammation in the central nervous system thought to be provoked by an infectious cause or occurring post vaccination
Features:
- Multifocal areas of diffuse inflammation most often seen in the subcortical cerebellum, brainstem, and spinal cord
- Usually monophasic but can be recurrent
Symptoms:
- Encephalopathy: confusion, irritability, AMS (somnolence to coma)
- Multifocal deficits, fever, meningismus (headache, photophobia, stiff neck)
Imaging:
- Large (greater than 1 to 2 cm) multifocal, hyperintense, bilateral, asymmetric lesions in the supra-/infratentorial white matter on T2-weighted or MRI FLAIR images
- Can be seen in gray matter, especially basal ganglia and thalamus
Resources:
Accute Optic Neuritis (AON)
Overview:
Optic neuritis is retrobulbar inflammation of the optic nerve that can occur spontaneously or be associated with other neurologic conditions such as MS, ADEM, NMO or lupus.
Features:
- Usually unilateral
- Dimished visual acuity, red color desaturation, afferent pupillary defect, and visual field deficits
Symptoms:
- Headache and painful eye movements
- Central visual blurring
- Dim vision
- Complete loss of vision
Imaging:
- MRI often shows gadolinium enhancement of the optic nerve
Resources:
Neuromyelitis Optica (NMO)
Overview:
Neuromyelitis Optica and neuromyelitis optical spectrum disorder (NMOSD) are inflammatory conditions of the central nervous system primarily targeting the optic nerve and spinal cord.
- Optic neuritis
- Acute myelitis
- Postrema clinical syndrome
- Acute brainstem syndrome
- Symptomatic narcolepsy or acute diencephalic clinical syndrome with NMOSD-typical diencephalic MRI lesions
- Symptomatic cerebral syndrome with NMOSD-typical brain lesions
- More common in non-Caucasians, especially Asians
- Important to rule out sarcoid, SLE, Sjogrens or other vasculitis
Symptoms:
- Optic neuritis (see above)
- Transverse myelitis (see above)
- Intractable hiccups or nausea and vomiting
Resources: