7 - atypical optic neuritis

What is the age range for atypical optic neuritis?

patient under 20 or older than 50

Is atypical optic neuritis uni or bilateral?

bilateral

What are the signs/symptoms of atypical optic neuritis?

1. painless OR persistent pain that doesn't improve

2. progression of visual loss beyond 14 days + lack of recovery after several weeks

3. significant disc swelling

4. neuroretinitis

What is neuroretinitis (Leber's idiopathic stellate neuroretinitis)?

optic disc edema with macular star

What causes the macular star in neuroretinitis?

fluid leakage from optic disc into the OPL

What are the causes of atypical optic neuritis?

1. infection

2. post-infection or post-vaccination

3. sarcoid

4. autoimmune disease

What is important about the term "atypical optic neuritis"?

catch-all term and should never be sole diagnosis

What is sarcoidosis?

multisystem chronic inflammatory disorder characterized by inflammatory granulaoms in systemic organs

How does sarcoid present in the eye?

1. most commonly granulomatous uveitis

2. candle wax drippings along retinal veins

3. white retinal exudates + optic hyperemia

what causes cat scratch disease neuroretinitis?

bacterial infection → Bartonella henselae

what do you do when you suspect cat scratch disease neuroretinitis?

ask about contact with cats → bites or scratches

test for antibodies to Bartonella

What is Neuromyelitis Optica (Devic disease)?

demyelinating disease that preferentially affects ON and spinal cord

Who gets Neuromyelitis Optica (Devic disease)?

any age → mostly those in their 40s-50s

What are the signs of Neuromyelitis Optica (Devic disease)?

1. demyelination of optic nerve, chiasm, and spinal cord on MRI

2. bilateral atypical optic neuritis

3. severe vision loss

what is the MOA of Neuromyelitis Optica?

autoimmune attack on aquaporin-4 (AQP4) water channel within the optic nerves and spinal cords → demyelination and axon damage

What are the main differences between Neuromyelitis Optica (Devic disease) and MS?

NMO symptoms are more severe and acute episodes can have devastating, irreversible effects on vision

MS episodes are usually more mild (may or may not cause disability) and vision usually returns spontaneously

what is the difference in epidemiology of NMO and MS?

NMO: across the world, non-Caucasians

MS: temperate climates, Caucasians

How do you test for Neuromyelitis Optica (devic disease)?

aquaporin-4 IgG (AQP4-IgG) antibody

What is the treatment for Neuromyelitis Optica (devic disease)?

1. high dose IV steroids for symptoms or plasma exchange to lower levels of Abs if no response to steroids

2. immunosuppressants for maintenance and prevent relapses

How does Myelin oligodendrocyte Glycoprotein antibody associated optic neuritis differ from Neuromyelitis Optica (Devic disease)?

similar characteristics as NMO, but much better prognosis

How do you differentiate from Neuromyelitis Optica (Devic disease) and Myelin oligodendrocyte glycoprotein antibody associated optic neuritis?

blood test for antibodies