Neuro 2.2 Flashcards
1
Q
Nystagmus
A
- Rhythmic, to and from eye movement due to:
- Inability to maintain fixation
- Loss of normal inhibitory influences on eye movement control system
- Loss of normally symmetrical input from one of the vestibular pathways to the ocular motor nuclei (if asymmetrical one overrides the other, eyes would move In one direction more than the other)
2
Q
Nystagmus - Phases
A
- Slow phase - eyes drift away from fixation point slowly
- Rapid phase - saccadic movement back to fixation point
Described by:
- Amplitude (how far eyes move) - coarse or fine
- Frequency (how fast eyes move) - low, moderate, high
3
Q
Nystagmus - Eye Movements
A
- Jerk
- Slow drift, fast saccadic correction (zig-zag)
- Pendular (most common)
- Non-saccadic in both directions, slow (squiggly line)
- Mixed
- Different eye movement on different positions of gaze
- e.g. pendular in primary position and jerk on lateral gaze
4
Q
Nystagmus - Types and Causes
A
- See-Saw (vertical nystagmus where one eye goes up and the other goes down)
- Midbrain lesions
- Pituitary tumours
- Severe visual loss
- Downbeat (eye drifts up slowly and then a quick down motion to the centre)
- Cerebellum lesions
- Medulla lesions
- Idiopathic
- Upbeat (eye drifts down slowly and then a quick up motion to the centre)
- Medullary lesions
- Cerebellum lesions
- Benign positional paroxysmal vertigo
- Abducting nystagmus of INO
- Demyelination
- Brainstem stroke
- Periodic Alternating (alternating eye movement)
- Arnold-Chiari
- Demyelination
- Trauma
- Encephalitis
- Syphilis
- Posterior fossa tumours
- Visual deprivation
- Pendular nystagmus
- Demyelination
- INO
- Brain stem dysfunction
- Spasmus Nutans
- Idiopathic in children
- Glioma
- Gaze-evoked (no nystagmus in primary position but when px moves their eyes they can get nystagmus in other positions of gaze
- Drugs
- Alcohol
5
Q
Nystagmus - Associated Symptoms
A
- Symptoms of demyelinating disease (loss of vision, eye pain, numbness, weakness, paraesthesia)
- Vertigo or oscillopsia (feeling world around you is moving) suggests vestibular system abnormality
- Deafness or tinnitus present in vestibular lesions
- Blurred vision
- Diplopia in particular positions of gaze (INO)
6
Q
Nystagmus - Ocular Motility
A
- Assess ocular stability in primary gaze (nystagmus? type?)
- Examine in 9 cardinal positions to determine if:
- Monocular or binocular?
- Conjugation - do eyes behave similarly?
- Abnormal movements are hor/vert/tors/mix?
- Abnormal movements are continuous or induced by particular eye positions?
- Slow/fast/both phases seen?
- Null point? (advise px’s to move tasks to area of least nystagmus)
- Head position, movements (adv may get a sore shoulders/neck due to holding head in abnormal position)
- Visual fields
- Romberg test - checks whether vestibular system affected
- Ask px to hold arms out, close eyes to see if they can stand still or whether they fall to one side - would suggest problem with vestibular system
7
Q
Nystagmus - Management
A
- Acquired - investigate for cause (urgency for referral depends on likely cause)
- Advice - null position, head position etc
- Refractive management, spectacle choices (especially when presbyopic - add may be slightly higher)
8
Q
Migraine
A
- Periodic headaches with complete resolution between attacks
- 80% have 1st attack before 30yrs
- Prevalence increases until 40yrs then decreases
- Twice as common in women
- Affects 7% of men and 20% of women
- 15% of females only have attacks around menstruation
9
Q
Migraine - Associations
A
- Certain foods (cheese, chocolate, coffee, red wine)
- Nausea or vomiting
- Photophobia
10
Q
Migraine - Attack Stages
A
- Prodrome (feeling of being unwell, know migraine is about to happen)
- Aura (visual disturbance, motor or sensory disturbance)
- Headache
- Resolution
- Not all migraines will have all 4 stages above
- Relieved by sleeping or going into a dark room
11
Q
Types of Migraine
A
- Common migraine
- Classical migraine
- Cluster headache
- Focal migraine
- Migraine sine migraine
- Retinal migraine
- Ophthalmoplegic migraine
- Familial hemiplegic migraine
- Basilar migraine
12
Q
Common Migraine
A
- Migraine without aura (migraine without aura 3x more common than migraine with aura)
- Headache and ANS dysfunction (pallor, nausea)
- Prodrome - changes in mood, yawning, poor concentration
- Headache - pounding or throbbing, can start anywhere and spreads to half or whole head, photophobic and sensitive to sound
- Lasts from hrs to a day
13
Q
Classical Migraine
A
- Visual aura for about 20 mins
- Looks like a paracentral scotoma - bright, positive (can’t see an area of the VF, but it looks bright)
- Fortification spectrum (jaggy lines) enlarges after a few mins, lined on inner edge with negative scotoma
- Positive scotoma, jaggy lines that start small get bigger and move across VF and then disappear (over 20 mins) with full visual recovery
- Scotoma expands and moves towards temporal periphery before breaking up
- Full visual recovery within 30 mins, if lasts more than an hour think of other causes
- Headache follows, usually opposite where the scotoma was
- Associated with nausea and photophobia
- Can vary in severity depending on px - headache can be absent, trivial, severe
- Visual aura without headache not uncommon in over 40s but always be a history of classical migraine in early 20s
*Positive scotomas - seen by the px (e.g. coloured light seen after staring at light for too long)
*Negative scotomas - blank spot in VF not seen by px (e.g. blind spot
14
Q
Cluster Headache
A
- Typically affects men in 30s and 40s
- Characteristic description of headaches - few headaches over a short period of time
- Can be almost every day for a period of weeks, can go years between clusters
- Severe headaches start suddenly
- Lasts 10 mins to 2 hrs
- Associated with ocular features, can be misdiagnosed as another ocular problem (lacrimation, conjunctival injection and rhinorroea)
15
Q
Focal Migraine
A
- Symptoms of migraine
- Transient dysphasia (language impairment - problems talking)
- Hemisensory symptoms
- Focal weakness
16
Q
Migraine sine Migraine
A
- Episodic visual disturbances without headache
- Typically elderly with history of classical migraine
17
Q
Retinal Migraine
A
- Rare
- Unilateral visual loss
- Differential diagnosis retinal embolism
- Similar to classical migraine but unilateral visual loss
- Permanent visual loss common with recurrent episodes
- Typically affects young women
18
Q
Ophthalmoplegic Migraine
A
- Rare
- Usually starts before age 10
- Recurrent headache followed by a 3rd nerve palsy
- Due to demyelinative diseases in most cases