Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

3F: Neuro Final > Optic Neuritis III > Flashcards

Optic Neuritis III Flashcards

1
Q

Appearance of optic disc edema

A
  • Swollen nerve fibers
  • Blurred margins
  • Edema of the peripapillary NFL (Paton lines)
  • secondary vascular dilation and leakage
  • loss of spontaneous venous pulsation
  • loss of the physiologic cup
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Circulation to the optic disc

A

SPCA

CRA (surface of optic disc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

General hemodynamics patterns

A

Mean arterial pressure of the arteries entering the eye is around 65mmHg. The pressure in the episcleral veins leaving the eye is around 15mmHg
Ocular profusion pressure (OPP)=diastolic BP-IOP. Perfusion pressure in th eye is approximately 50mmHg.
Reduction of OPP causes hypoxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When ocular perfusion pressure drops below the osmotic pressure

A

The caps collapse resulting in perfusion crisis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Stasis of axoplasmic flow

A

Non vasculitis ischemia

  • alteration in pressure/perfusion ratio
  • occlusion of disc vessels
  • occlusion of the peripapillary vessels

Vasculitis (inflammation)

Mechanical

  • infiltrative: neoplastic/inflammation
  • compartment syndrome
  • high ICP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Ischemic optic neuropathy

A

AION: arteritis (GCA)
NAION: nonarteritic ION
DION: diabetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

AION

A
  • NAION vs AION 10:1
  • sudden unilateral painless VA loss 20/200 or worse with poor recovery
  • often becomes bilateral
  • 70-80 year old female > male
  • not particularly assocaited with risk factors: smoking, DM, overweight, HTN, cholesterol, inactive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

AION: GCA

A
  • inflammation of the elastic later of medium to large arteries
  • veins are not affected
  • granulomatous inflammation occurs in the vessels supplying the eye cause thrombosis, then occlusion of arteries, and ischemic infarct of optic nerve head
  • regional ischemia to peripapillary tissue
  • GCA at a remote location will have downstream events: jaw claudication, scalp tenderness, neck pain and trouble focusing; fever, HA, weight loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Anteiror ischemic signs of AION

A 
Tortuous conjunctival and episcleral vessels
Low grade ischemic uveitis 
Cornea edema 
Rubeosis irides and cataract 
Hypotony
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Posterior ischemic signs of AION

A

Chorioretinal degeneration
Choroidal ischemic lesions on FA
CRAO and cilioretinal artery occlusion
CWS near cilioretinal artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Weak perfused disc: AION

A

Pink to pale disc
Small linear flamed shaped hemorrhages
Edema and elevation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Severe occlusive disease: AION

A

Chalk white disc

Edema and elevation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Severe functional deficits of the disc: AION

A

BCVA 20/200 or worse, vision does not recover

RAPD, Pulfrichs distortion, CV defects

VA defects more extensive than in NAION

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Reolsved AION disc sign

A

Pale disc often with glaucomatous excavation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pulfrich Effect

A

-it can be tested for in the office. Is a stereo illusion in which a to and fro motion in the plane facing the subject is seen as an elliptical movement by an individual with a unilateral optic neuropathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

AION managment

A
  • affected eye rarel recovers
  • fellow eye needs protected
  • ESR, CRP, CBC, serum fibrinogen, platelet counts (ESR: men age/2, women age+10/2)
  • temporal artery biopsy within 1 week after stating steroids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What confirms diagnosis of GCA

A

Temporal artery biopsy

-you may need to repeat if negative because it has skip lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

1 month after GCA AION

A

OCT reveals decreased macular ganglion cell layer thickness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

NAION profile

A
  • whites
  • males
  • sudden unilateral painless vision loss
  • ages 50-70 with peak 55-65 (younger than AION)

Association’s
- compartment syndrome: disc at risk-always examine the other eye and record C/D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Pathophysiology of NAION

A

Hypoperfusion
Acute ocualr hypotensive crisis. Need a nocturnal reduction in BP
Defective autoregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

NAION: static form

A

75%

  • acuity 20/40-20/200
  • better VA than arteritic
  • altitudinal VF defects is classic
  • affluence defects
22
Q

NAION: progressive form

A

25%

  • stepwise reduction in vision
  • steady decline (weeks to months)
  • VF defects much more variable
  • afferent defects
23
Q

NAION disc appearance

A

Segmental to complete optic disc edema

Resolved NAION shows disc pallor, but does not tend to show disc excavation

24
Q

Fellow eye invovlemt in NAION

A

15-25% of patients over 5 years (up to 30 years)
More likely if diabetes, anemia, younger age
More likely if first <20/200 at onset

25
Q

Management of NAION

A

Most texts recommend observation since it is often too late to make a difference

If caught early enough

  • systemic steroids
  • IV avastin
  • reduce IOP
  • blood thinners

Surgical procedures

  • ON decompression
  • radial neurotomy
  • vitrectomy
26
Q

Ischemic optic neuropathy decompression trial results

A

6 months: not good outcomes

After 24 months: not good outcomes

Don’t recommend this surgery

27
Q

Macula and NAION

A

There could be some macular complications, so we would need to start treatment for them.

28
Q

DION (DM)

A

Type I or II
Young or old
Unilateral or bilateral
Diabetic retinopathy usually present

29
Q

Bialteral DION DiffDx

A

Mimic papilledema

30
Q

Retrobulbar optic neuritis

A

No visible signs initially; pallor may ensue

31
Q

Optic neuritis profile

A
  • any age
  • favorable prognosis
  • if onset of VA is 20/200 or worse, poor prognosis
  • devic’s disease usually progresses to poor vision
32
Q

Pathophysiology of Optic neuritis

A
  • idiopathic
  • AI
  • infiltrative processes
  • infections
  • demyelination (MS, Devic’s are the most common causes)
33
Q

Papillitis in optic neuritis

A

-overlying vitreous cells may be present
-mild to severe disc edema
-mild to severe vascular engorgment
0spinter disco hemorrhages and peripapillary hemorrhages
-edema nad exudates

34
Q

Retrobulbar neuritis

A

No visible disc signs

35
Q

Presentation of optic neuritis

A

Ocualr pain on eye movement

  • differentiates from other optic neuropathies
  • more common in retrobulbar neuritis
36
Q

Clinical course of optic neuritis

A

Initial VA is not predictive of outcome

37
Q

Adult optic neuritis

A 
Unilateral
Retrobulbar
EOM pain
Most often idiopathic 
High probability of recurrent demyelainting event and MS
38
Q

Pediatric optic neuritis

A

Bilateral
Papillitis
HA
Most often post infectious or post immunization
Low probability of recurrent demyelination gets event and MS

39
Q

Presentation of optic neuritis and MS

A
  • most often retrobulbar
  • maybe assorted with periphlebitis
  • typically tenderness of globe on OEM
  • recurrent pattern
40
Q

Overall odds ratio of developing MS after optic neuritis

A

50%

41
Q

Optic neuritis treatment trial

A
  • optic neuritis treatemtn trial found that most patients recover with or without therapy
  • IV plus oral therapy speeds the recovery of optic neuritis, reduces the risk fo MS development for the first two years, but does not offer any long term benefit regarding visual outcome or development of MS
42
Q

Managment of optic neuritis

A

Patient should be counseled that visual prognosis is good with or without treatment

MRI recommended to ascertain future risk
-if abnormal disease modifying therapy should be considered to lower conversion to MS

43
Q

Devic’s disease

A

Optic neuritis plus 2 of the following

  • lesions expending over 3 vertebrae of spine
  • absence of MRI findgins indicating MS at onset
  • IgG serum autoantibodies against AQP4
44
Q

High ICP and optic neuropathy

A

Papilledema

45
Q

Papiledmea

A
  • bialteral optic disc edema due to increased ICP
  • any age
  • visual function preserved but may suffer reduction in chronic cases
  • mass lesions
  • medications
  • lead toxicity
  • HTN
  • blood dyscrasias
46
Q

Presentation of papilledema

A

V A generally preserved

If it is reduced, its an emergency (either way it is an emergency)

47
Q

Acute papilledema fundus signs

A

Bialteral optic disc edema, may be assymetricla

Generally marked elevation: Halo and Patons line

48
Q

Presentations of papilledeam (acute)

A

Blind spot enlargement

49
Q

Chronic papilledema

A

Blind spot enlargement
Loss of central acuity from optic atrophy
Optociliary shirt vessels

50
Q

Managment for papilledema

A

Immediate referral to neurologist for PCP for MR/CT scan

Serial lumbar puncture

51
Q

Pseudotumor cerebri

A

Often occurs in young females with recent weight gain

Diagnosis of exclusion

  • negative MRI with normal to small ventricles
  • negative CSF analysis
  • normal CBC

If normal weight consider

  • infection
  • sarcoidosis, SLE, MS, Reye

3F: Neuro Final (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions