Optic Nerve Disease

1. Optic Nerve Disease Kelli Shaon, O.D.

2. Congenital Optic Nerve Abnormalities

3. Morning Glory Disc • Unilateral, Larger nerve head • Funnel shaped nerve head surrounded by chorioretinal pigment changes • Vessels of the nerve head often appear hidden by glial tissue centrally • **Strong association with non-rhegmatogenous RD

4. Optic nerve head Coloboma • Unilateral, larger affected nerve • Often has unusual vascular pattern • Is the absence of tissue (retina, choroid, &/or ON) • Usually inferior portion ON • Vision varies (depends on severity) & VF defects vary (but are often dramatic) • **Strong association with non-rhegmatogenous RD

5. Optic Pit • Often appear as greenish-gray discoloration in area of ONH • Often inferior temporal (due to incomplete fetal fissure) • VF defects present that corresponds with pit location • **High Risk of Macular Serous Detachments

6. Optic Nerve Hypoplasia • Often unilateral but can be bilateral • Nerve head is typically 1/2 to 1/3 normal size • ON often surrounded by yellowish (or pigmented) zone – that would equal the size of the normal nerve • Called Double-ring sign • Vision if often decreased, & nystagmus can be present (due to ↓ VA since birth) • Strong association with systemic abnormalities (especially if bilateral)

7. Megalopapilla • Term used to describe larger ON when compared to fellow nerve • Diagnosis of exclusion (have to r/o of abnormalities) • Often has a larger C/D ratio

8. Optic Nerve drusen • Present in 1% of population • Higher incidence in Caucasians • Calcified hyaline bodies that are anterior to the lamina cribosa • In younger pts (children) can appear to be papilledema-like (no cupping), then with age appear to be yellowish, bumpy spherical retractile bodies superficial in ON • The deposits can cause interruption of axoplasmic flow which then may lead to VF defects that are known to progress • Deposits may also shear blood vessels causing hemorrhages which can affect vision

9. Optic Nerve drusen • Can autofluorescence w/ red-free filter • Hyperfluorescence on FA • Can interrupt axoplasmic flow, and interfere w/ vision & cause VF defects • Demonstrate highly reflective on ultrasound (B scan) • If extremely large drusen, can show up on CT

10. Common Benign Conditions • Pre-papillary Loop – thought to be an embryonic vessel • Ascends from the disc back to the disc • Projects into the vitreous & may move w/ eye movements • Cilioretinal Artery – derived from short posterior ciliary circulation • Occur in ~20% of individuals • Appears to start at temporal edge of disc & extend to macula • Supply inner retina & papillomacular bundle • Myelinated Nerve Fibers • Continuation of myelinated tissue anterior to the lamina • Appears as feathery superficial retinal opacification • May cause some VF depression

11. Common Benign Conditions

12. Common Benign Conditions • Tilted Discs – usually inferior-nasal tilt • Malinsertion syndrome - is tilted temporally (nasal disc is slightly elevated)

13. Leber’s hereditary Optic Atrophy • Bilateral • Acute presentation of rapid visual loss of 1 eye followed by the other eye within days or weeks • Average age of those affected 24 yo • Men>> Women (6.7 to 1) • Inherited by a mitochondrial DNA - (need genetic counseling) • Not transmitted by males • Transmitted (in carrier state) by females to 100% of daughters • Transmitted by females to manifest in 50% of sons • Transmitted by females to manifest in 10% of daughters

14. Leber’s hereditary Optic Atrophy • Presentation: • Acute onset: optic disc edema with accompanied small telangiectatic vessels near the disc (do not leak on IVFA) • Later stage: Followed by Severe optic atrophy • Visual acuity of 20/200 or worse & cecocentral VF defects • Management: • Genetic counseling • Low vision examination

15. Acquired Optic Nerve Disease

16. Optic Neuritis (Papillitis) • Refers to “inflammation” of the optic nerve • Helpful to categorize optic neuritis as one of the following: • (1) Inflammatory-infectious (viral or bacterial) • (2) Demylinizing (multiple sclerosis) • (3) Idiopathic • Optic neuritis is most often associated with MS • If inflammatory or infectious – more likely to have swollen disc (ophthalmoscopy signs)

17. Optic Neuritis 2° to MS • Symptoms/Signs: • Unilateral loss of vision over hours to days • Pain is often associated with eye movement • If retrobulbar, no ophthalmoscopy signs may be seen – “Patient sees nothing and doctor sees nothing” • Decreased color perception – desaturation of “Red Cap” • Pulfrich phenomenon (altered perception of moving objects) • Increased symptoms with increased body temperature (most notable after hot shower or exercise) – Uhtoff’s sign • (+) APD • VF defects – central, cecocentral, arcuate or altitudinal

18. Optic Neuritis 2° to MS • Observations: • Optic nerve appears normal (retrobulbar) in 2/3 of cases • Optic nerve swelling is present in 1/3 of cases • Optic nerve head swelling does NOT correlate with severity of ON dysfunction • Flame shaped hemorrhages may be seen, but uncommon

19. Optic Neuritis 2° to MS • Management/Treatment: • Referral to a neurologist • MRI – often shows plaques formation • Presence of 1 or more plaques – 56% will develop CSMS • No plaques – 22% will develop MS • Steroids? Vs. Interferon therapy vs. No treatment • Outcome: • ~90% of pts will have visual recovery to 20/40 better within a few weeks • Recovery nearly complete by 5 weeks after episode

20. Optic Neuritis Treatment Trial • Used 3 treatment groups for Isolated Optic Neuritis: • IV methyprednisolone x3d, followed by PO prednisone taper • PO prednisone • Oral placebo for 14 days • Outcome: • At 6 months, visual recovery was the same for all 3 groups • 5 year follow-up : showed 87% of pts were 20/25 or better (despite treatment) • ** However, the ONTT demonstrated the use of PO steroids was associated with an increased risk of recurrent optic neuritis – DON’T USE PO STEROIDS ALONE • So Tx can be IV steroids, with PO taper OR no treatment

21. Controlled High Risk Avonex Multiple Sclerosis Prevention Study (CHAMPS): • Eligibility criteria: • Abnormal MRI – 2 or more lesions (min of 3 mm) • First neurological event (including optic neuritis) • Treatment groups: • Interferon-beta-1a (Avenox) – weekly IM injection followed by IV steroid x3d, then PO steroid 11 days • Weekly placebo IM injection followed by IV steroid x3d, then PO steroid 11 days • Results: • Avonex had a 44% reduction on the 3 year risk of CSMS when compared to placebo

22. Papilledema • Def: Optic disc edema produced by increased intracranial pressure • Symptoms/Signs: • Acute onset: • Bilateral (may be asymmetric) optic disc edema & hyperemia • Loss of SVP • Blurring of disc margins often obscuring disc vessels • NFL is often opacified • Disc hemes or CWS • Chronic papilledema • Resolution of hemes/CWS • Optic atrophy • Optociliary shunt vessels may develop • Transient visual disturbances, often w/ postural changes – lasting seconds • Headache • Enlarged Blind spot of VF testing – may expanded with time

23. Papilledema • Differential Diagnosis: • Long list – see Will’s for details • Work-up: • MRI/CT scan – to determine if space occupying lesion (tumor) • Lumbar puncture (LP), if CT or MRI does not reveal cause • Treatment: • Treat cause of increased ICP

24. Papillits vs. Papilledema • Papillitis is differentiated from papilledema • Unilateral instead of bilateral • Shows less elevation of the nerve head, and sluggish pupillary response • Will you get a APD with papilledema or a ↓ in color vision? • Not usually (rare exception - in chronic cases) but will in papillitis • When is the one exception when you can have unilateral “papilledema”? • Foster-Kennedy Syndrome is characterized by papilledema in one eye and optic atrophy in the other – This results from simultaneous raised ICP and optic nerve compression secondary to tumor

25. Pseudotumor Cerebri (PTC) • Symptoms/Signs: • Bilateral disc edema 2° to increased ICP (in the absence of space occupying lesion) • Headache (usually severe) – worse in the AM • Nausea &/or vomiting • Transient visual disturbances • Diplopia • Associated factors: • Female >>> male • Usually between 10-50 years of age • Obesity – ** Mnemonic – “Fat, Fertile, Female” • Pregnancy • Medications – (PO contraceptives, TCN, Vit A & PO steroid withdrawal)

26. Pseudotumor Cerebri (PTC) • Work-up: • MRI/CT scan to r/o tumor • LP - results often > 200 mm of water • Treatment: • Weight loss – if associated • Acetazolamide – Diamox PO 250 mg qid • Optic nerve decompression • Lumoperitoneal shunt

27. Ischemic Optic Neuropathy • Two types: • Non-artertic ischemic optic neuropathy (NAION) • Artertic ischemic optic neuropathy (AION) • They are NOT the Same – Must differentiate • After acute episode – 90% of AION will have cupping of the nerve compared to only 2% of NAION

28. Artertic Ischemic Optic Neuropathy(AION) • Etiology: Giant Cell Arteritis (GCA) • ***Ocular emergency *** Vision loss can become bilateral within hours to days • Almost always affects those > 50yo (w/ a mean age of 70+ yo) • High incidence of morbidity &/or mortality associated with GCA • Need to notify PCP immediately

29. Artertic Ischemic Optic Neuropathy(AION) • Signs/Symptoms: • Sudden, painless loss of vision (amaurosis fugax) – often CF or worse • Diplopia • (+) APD • (+) Altitudinal VF defect • Pale Diffuse edematous disc • Disc hemes possible • CRAO also possible (may be presenting sign) • Weight loss, fatigue, jaw claudication, temporal scalp tenderness, proximal muscle/joint pain (polymyalgia rheumatica), decreased temporal artery pulsation

30. Artertic Ischemic Optic Neuropathy(AION) • Work-up: • STAT Sed Rate (ESR) - Often extremely elevated • Normal: Male=(Age/2) Female= [(Age+10)/2] • C Reactive protein (CRP)– Often elevated • A elevated Sed rate & Elevated CRP = 97% specific for diagnosis of GCA • CBC w/ diff – often have anemia & thrombocytosis • Temporal artery biopsy – look for presence of arterial lumen damage & mononuclear cells • Treatment/Management: • No vision loss: PO steroids  60-100mg/day, taper • Acute Vision loss: Admit to hospital -- IV steroids (250mg q6h x12 doses), followed by PO steroids (slow taper)

31. Non-Artertic Ischemic Optic Neuropathy (NAION) • Etiology: Often vascular (Arteriosclerois, HTN, DM, anemia, and sleep apnea) • Thought to occur due to nocturnal hypotension • Often associated with a “disc at risk” – no/small physiologic cup • Diagnosis of exclusion- need to r/o of AION vs. other etiology

32. Non-Artertic Ischemic Optic Neuropathy (NAION) • Signs/Symptoms: • Sudden, painless loss of vision (amaurosis fugax) • Vision loss not usually as severe as in AION • (+) APD • (+) Altitudinal VF defect • Pale segmental swollen disc • Management/Treatment: • ESR, CRP, CBC w/ diff – to r/o out AION • Consider MRI/CT scan if compressive lesion is DDx • Measure blood pressure in office • Medical evaluation by internist or PCP • Follow-up 1 month or PRN based on severity

33. Compressive Optic Neuropathy • Signs/Symptoms: • Slowly progressive visual loss • (+) possible APD • VF defects – usually central • Proptosis • ON can be pale or swollen (varies) • Optociliary shunt vessels – vessels that shunt blood from the retina to the choroidal circulation)

34. Toxic/Nutritional Optic Neuropathy • Painless, progressive bilateral loss of vision • Bilateral cecocentral or central VF defects • Reduced color vision • Temporal disc pallor • Possible optic atrophy • Etiology: Alcohol, Malnutrition, B12 anemia (pernicious), other toxic substances • Work-up: History (alcohol or drug abuse, diet), B1, B12, Folate, CBC, heavy metal screening