Brainscape's Knowledge GenomeTM

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


See full index

OPM > Systemic Disease and Optic Nerve > Flashcards

Systemic Disease and Optic Nerve Flashcards

1
Q

Anatomy of Optic Nerve?

  1. How many fibres? Type of nerve fibres? Origin?
  2. Where do they synapse?
  3. Where do fibres subserve in Visual Field?
A
  1. 1.2 million afferent nerve fibres
    Originate in the retinal ganglion cells
  2. Most synapse in the lateral geniculate body (some go to the pre-tectalnuclei in the midbrain)
  3. About 1/3 of the fibres subserve the central 5°of the visual field
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the optic disk?

  1. Shape?
  2. Colour?
  3. Diameter?
A
  1. Circular or oval structure
  2. Pale pink.
    The temporal side being slightly lighter than the nasal
  3. ~1.5mm in diameter
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  1. What does optic disc contain?
  2. Describe disc edge?
A
  1. The centre has a small depression = physiological cup.
  2. Disc edges are flat and well defined and the temporal edge is more distinct than the nasal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  1. What is pigmented arc?
  2. What does it make up of?
A
  1. It is formed when retina does not reach the optic disc margin
  2. Choroidal pigment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  1. What artery is in Optic disc?
  2. What are their branches?
A
  1. The central retinal artery appears on the surface of the optic disc.
  2. It divides into two branches: superior & inferior
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  1. Where do optic nerve fibres become myelinated?
A
  1. Lamina cribrosa ( where they exit eyeball)
    ( Image: paler sheathing, fibres are arcuated)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Anatomical subdivisions

  1. How long is the optic nerve between globe to chiasm?
  2. How many segments? How are they subdivided?
A
  1. 50mm
  2. 4 segments
    Intraocular

Intraorbital

Intracanallicular

Intracranial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Signs of Optic nerve problems?
1. VA?

  1. Pupil?
  2. Colour vision
  3. Sensitivity?
  4. Any visual field defects?
A
  1. VA decrease
  2. Afferent pupil defect
  3. Dyschromatopsia
  • Colour vision impairment
  • Mainly affects red or green
  • Quick assessment: ask patient to compare colour of a red object
  1. Diminished light brightness sensitivity
  2. Visual field defects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Underlying disease?

  1. How to find out underlying disease?
  2. What factors to be considered?
A
  1. Careful examination & history taking is essential !!!
  2. Consider:
  • Raised ICP
  • Intracranial hypertension: associated with prescription & non-prescription drugs
  • Ischaemia: Associated with atherosclerosis, diabetes & giant cell arteritis
  • Thyroid disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Optic Atrophy Signs?

Primary

  1. Apperance of ONH?
  2. What cause (1)?
  3. Appearance of optic disc? Margin?
  4. Vessels on disc surface?
  5. NFL?
A

Primary

  1. No swelling at ON head
  2. Caused by lesions of visual pathway
  3. Pale flat disc with clear margins
  4. ↓ # of vessels on disc surface (Kestenbaum sign) with attenuation
  5. Thinning of NFL

Secondary

  1. Occurs after swelling at ON head
  2. White or grey slightly raised disc- Blurry margins
  3. Kestenbaum sign
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Optic Atrophy Causes?

PRIMARY?

A
  • Retrobulbar neuritis
  • Compression
    Tumour
    Aneurysm
  • Hereditary neuropathies
  • Other neuropathies
    Toxic
    Nutritional
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Optic Atrophy Causes

Secondary?

A
  • Papilloedema
  • Anterior ischaemic optic neuropathy
  • Papillitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

OPTIC NEURITIS

  1. What is it?
  2. How is it classified ?
A
  1. Inflammation , infection or demyelination of optic nerve
  2. By appearance or aetiology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

OPTIC NEURITIS

Classification?

A
  1. Retrobulbar neuritis
  2. Papillitis
  3. Neuroretinitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Charateristics of Optic neuritis ?
Describe ONH, Optic disc, RNFL?

A
  1. Retrobulbarneuritis

ON head looks normal initially

Associated with MS

  1. Papillitis
    Affects ON head
    Disc becomes oedematous
    Associated with peripapillaryflame haemorrhage
  2. Neuroretinitis
    Affects ON head (papillitis)
    RNFL inflammation & macular star
    Least common type of neuritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Differential diagnosis of macular star?
Other disorder causing macular star?

A

Hypertensive retinopathy

  • Also have cotton wool spots
  • Hard exudate ( due to hypertension)
  • Some haemorrhage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

OPTIC NEURITIS

Classification by aetilogy?

A
  1. Demyelinating
  2. Parainfectious
  3. Infectious
18
Q

Optic Neuritis - Demyelinating
Consequences?

Causes?

A
  • Myelin is lost from nerve fibres
  • Disrupts nervous conduction
  • Can be caused by diseases such as:
    Isolated optic neuritis
    Multiple sclerosis
19
Q

Optic Neuritis & Multiple Sclerosis

Associated with any systemic disease clinically?

A
  • Some patients with optic neuritis have no clinically demonstrable associated systemic disease but a close association exists between the two
  • ~ 15-20% of MS patients present with optic neuritis and optic neuritis occurs at some point in 50% of patients with MS
20
Q

Optic neuritis -demyelinating

  1. Age group
  2. VA? Prognosis of VA?
  3. Signs and Symptoms?
A
  1. Presentation b/w age of 20 & 50
  2. Monocular VA decrease (6/18-6/60), VA recovers to 6/9 or better in 75% of cases
  3. Phosphenes = white/coloured flashes/sparkles

•Discomfort/pain, especially on ocular movement

•Afferent pupil defect

21
Q

Optic neuritis -demyelinating
Visual field defect?

A
  • Visual field defects are often present
    ↓ sensitivity in central 30°
  • Nerve fibre bundle defects and
    Central scotomas
    Focal defects
22
Q

Optic neuritis -parainfectious

  1. Causes? What kind of infections?
  2. When do they occur?
  3. Who are more likely to be affected?
  4. What do patients present with?
  5. Optic disc appearance?
A
  1. Viral infections: Measles, mumps, chickenpox, rubella, whooping cough and glandular fever
  2. Occur following immunization
  3. Children affected more frequently than adults
  4. Presentation usually 1-3 weeks following a viral infection with acute severe visual loss (can be bilateral)
    Other neurological features:headache, seizures or ataxia
  5. Papillitis seen at the optic disc or can look normal
23
Q

Optic neuritis -infectious
Associate with what kind of infections?
Hint: 6 !
S C S L C V

A
  1. Sinus infection which spreads and puts pressure on the nerve
  2. Cat-scratch fever
  3. Syphilis
  4. Lyme disease (infection from a tick bite)
  5. Cryptococcal meningitis (seen in AIDS patients)
  6. Varicella zoster virus
24
Q

Optic neuritis –non-infectious

  1. Who does it affect?
  2. ON appearance?
A
  1. Affects about 1-5% of patients with sarcoidosis
  2. Often the optic nerve looks similar to the way it looks with MS
25
Q
A
26
Q

OPTIC NEUROPATHIES
Types?

A
  1. NAION: Non-arteritic anterior ischaemic optic neuropathy
  2. AAION: Arteriticanterior ischaemic optic neuropathy
  3. PION: PAPILLOEDEMA
27
Q

NAION

Non-arteritic anterior ischaemic optic neuropathy

  1. Who are prone?
  2. Cause?
  3. Age?
A
  1. The elderly
  2. Infarction of the optic nerve head b/c of blockage of the short posterior ciliary arteries
  3. 55 and 70 years
28
Q

NAION

Non-arteritic anterior ischaemic optic neuropathy
Prediposing factors? ( 5)

A
  1. Hypertension, ↑ cholesterol
  2. Diabetes mellitus, Collagen vascular disease
  3. Sudden hypotensive events, Cataract surgery
  4. Sleep apnoea
  5. Taking “Viagra”
29
Q

NAION

Non-arteritic anterior ischaemic optic neuropathy
Signs, symptoms?

A
  • sudden, painless, monocular visual loss
  • vision is reduced upon waking
30
Q

NAION

Non-arteritic anterior ischaemic optic neuropathy
Clincal Consequences?

  1. Vision ?
  2. VF defect?
  3. Colour vision loss?
  4. Optic disc?
A
  • ↓ vision ~1/3 of patients will have normal/near normal vision
  • VF defect: Often inferior altitudinal
  • Colour vision loss
  • Swollen optic disc

Image:

​a. Swollen disc, diffuse oedema

b. Blurred edge, sectorial haemorrage
c. haemorrage at Superior nasal sector
d. leaking blood - lack of perfusion

31
Q

AAION

Arteriticanterior ischaemic optic neruopathy

  1. Cause?
  2. Present with?
  3. Other signs & symptoms?
A
  1. Caused by Giant Cell arteritis
  2. Sudden & severe unilateral visual loss
    periocularpain
    Possibly flashing lights (photopsia)
  3. Other signs/symptoms
    Jaw claudication
    Headache of recent onset
    Scalp tenderness
    Weight loss
    History of polymyalgiarheumatica
32
Q

AAION

Arteriticanterior ischaemic optic neruopathy

A
33
Q

NAION vs AAION

Comparison

  1. Vision loss ? Sign & Symptoms?
A
34
Q

PAPILLOEDEMA

  1. Optic nerve head appearance?
  2. Causes?
  3. Link to intracranial mass?
A
  1. Swelling of ONH, secondary to raised intracranial pressure (ICP)
    Usually bilateral, could be asymmetrical
  2. Other causes of disc oedema in the absence of raised ICP are referred to as ‘disc swelling’ and usually produce visual impairment.
  3. All patients with papilloedema should be suspected of having an intracranial mass unless proved otherwise!!!
35
Q

Papilloedema

  1. Signs? Symptoms?
A
  1. Headache
  • Sudden nausea & vomiting
  • Drowsiness or deterioration of consciousness
  • Transient visual obscurance
  • Horizontal diplopia (c/b CN VI palsy)
36
Q

Papilloedema

Stages?

A

4 stages:

  1. Early
  2. Established
  3. Chronic
  4. Atrophic
37
Q

Papilloedema

Stage 1- Early

  1. Symptoms? Vision?
  2. Optic disc?
  3. Disc margin?
A
  1. No symptoms, normal vision
  2. Mildly elevated discs
  3. Indistinct disc margins i_nitially nasal_, later superior, inferior and temporal
38
Q

Papilloedema

Stage 2 -Established

  1. Symptoms? Vision? VA?
  2. Optic disc?
  3. Fundus appearance?
A
  1. Transient visual obscurations, lasting a few seconds
    VA is normal or reduced
  2. Optic discs elevated with indistinct margins
  3. Venous engorgement, peripapillary flame-shaped haemorrhages and CW spots
39
Q

Papilloedema -Established

  1. Changes in ONH? Cause?
  2. Centre of fovea appearance?
  3. Blind spot?
A
  1. As the swelling increases, the optic nerve head appears enlarged
  2. Hard exudates may radiate from the centre of the fovea in the form of a ‘macular fan’ -an incomplete star with the temporal part missing
  3. The blind spot is enlarged
40
Q

Papilloedema -Chronic

  1. VA?
  2. VF?
  3. Disc?
  4. Fundus apperance?
A
  1. Variable VA
  2. VF constriction
  3. Elevated discs
  4. No CW spots or haemorrhages
41
Q

Papilloedema -Atrophic
1. VA?

  1. Optic disc? Colour? Margin?
A
  1. Severe VA impairment
  2. Discs dirty grey in colour
    * *Elevated**
    * *Indistinct** margins

OPM (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions