DIS - Optic Nerve III - Week 10 Flashcards
Do inherited neuropathies always manifest at birth?
no, they may not manifest until later in life
What is the major acquired optic neuropathy?
Glaucoma
Define neuropathy.
Ongoing and premature loss of optic nerve fibres beyond normal ageing
What is the end point of any neuropathy?
Atrophy
Differentiate between papilloedema and optic disc oedema.
Papilloedema - bilateral swollen discs due to raised intracranial pressure
Optic disc oedema is generalised oedema with many other causes
Describe the timeline of acute and chronic neuropathy to atrophy (3 each).
Acute - disc oedema, vascular compromise, necrosis > optic atrophy
Chronic - apoptosis, loss of nerve fibres, cupping/pallor > optic atrophy
Describe the stages of disc oedema by the amount of disc involved (3).
Partial
Sectoral
Total
Describe the stages of disc oedema by the visibility of vessels and structures (2).
Early - majority of structures visible
Severe - obstructed view
Compare the appearance of acute and chronic disc oedema.
Acute - messy
Chronic - clean, champagne cork
List five tests that assess optic nerve function.
Swinging flashlight test Monocular vision Monocular colour vision loss (ishihara) Colour comparison - red cap Brightness comparison (max brightness on ophthalmoscope, same principle as red cap testing)
Are inherited optic neuropathies common or rare? Are they easily diagnosed or commonly misdiagnosed?
Rare and often misdiagnosed
List the three main modes of inheritence for inherited optic neuropathies.
Autosomal recessive
Autosomal dominant
Mitochondrial
In what three ways could other cases be ruled out for inherited optic neuropathies.
Serology
Imaging
Dilated fundus exam
What mode of inheritence does Behrs syndrome have and how does it affect vision and from what age?
Autosomal recessive
Profound vision loss in neonates
What appearance does the disc have in behrs syndrome?
Chalky white disc
True or false
Nystagmus is not present with behrs syndrome
False, it is
Can a foveal reflex be seen with behrs syndrome?
No
What colour deficiency is present with behrs syndrome?
Red-green
List three systemic abnormalities of behrs syndrome.
Spastic gait
Ataxia
Mental handicap
What mode of inheritence does wolfram syndrome have?
Autosomal recessive
What kind of atrophy does wolfram syndrome have?
Diffuse severe optic atrophy
What is DIDMOAD and what disease is it for?
Diabetes insipidus Diabetes mellitus (type 1) Optic atrophy Deafness For wolfram syndrome
List four systemic associations of wolfram syndrome. How does it affect lifespan?
Ataxia Short stature Endocrine anomalies Mental impairment Short lifespan
What mode of inheritence does kjers disease have?
Autosomal dominant
What effect does kjers disease have on vision and at what age?
Mild chronic loss
How does the optic disc appear with kjers disease and what area specifically?
Temporal disc pallor
What kind of visual field defect occurs with kjers disease?
Relative central scotoma
What colour deficiency does kjers disease cause?
Blue-yellow
Are other neurological abnormalities common with kjers disease?
Uncommon
What is the most common inherited optic neuropathy?
Kjers disease
What is the most common mitochondrial disorder?
Lebers hereditary optic neuropathy
Between males and females, which is more affected by lebers hereditary optic neuropathy?
Males
How does lebers hereditary optic neuropathy affect vision?
Profound vision loss in young adults from 6/24 to NLP