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Have MULTIPLE questions about MULTIPLE sclerosis?
Having trouble seeing neuromyelitis optica?
In a fog about MOG?
Here’s the cheat sheet you NEED to distinguish the demyelinating diseases!
Demyelinating diseases predominantly involve the optic nerves, brain, & spine.
The three main chronic demyelinating diseases are Multiple sclerosis (most common), neuromyelitis optica (NMO), & myelin oligodendrocyte glycoprotein (MOG) antibody associated disease or MOGAD
Each has its own features in the optic nerve, brain, & spine. Here’s how to remember them!
▶️MS
🔸Optic nerve:
--MS only has 2 letters, so MS involvement of the optic nerve tends to be short segment
🔸Brain:
--Letter M makes the shape of the perivascular distribution of lesions along the ventricles (Dawson’s fingers)
--Letter S makes the shape of the subcortical U fiber involvement
🔸Spine:
--MS is only 2 letters, so lesions are usually less than 2 vertebral bodies in length
▶️NMO
🔸Optic nerve:
--NMO is a longer abbreviation, three letters, so longer involvement
--NMO can stand for Near My Occiput. Occiput is posterior, so more posterior nerve involvement
🔸Brain:
--NMO can stand for Near My Ocean. What is your brain’s ocean? The ventricles. NMO lesions are all periventricular
🔸Spine:
--NMO is 3 letters, so lesions usually more than 3 vertebral bodies in length
▶️MOGAD
🔸Optic Nerve:
--Remember MO’ GAD-olinium. So things that cause more regions of enhancement. MOGAD lesions are commonly bilateral & long segment & enhancement can extend perineural
🔸Brain:
--Remember LO’ GAD. MOGAD typically involves the lower areas of the brain
🔸Spine:
--Remember MO’ PLAID. MOGAD can give a plaid-like H shape in the cord from predominantly gray matter involvement
Hopefully, this cheat sheet will help you remember how to distinguish the demyelinating diseases!
It ain’t lyin’ about diseases of myelin!