Acute neurological complaints Flashcards
T/F the brain is insensate
T
What structures in the head can cause headache, given that the brain iteself is insensate
Traction or dilatation of intracranial vessels
Traction of large extra cranial veins
Compression, traction or inflammation of cranial and spinal nerves
Meningeal irritation and raised intracranial pressure
Spasm or trauma to cranial or cervical muscles
Disturbance of serotonergic projections
Primary headaches
Migraine
Tension Type
Cluster Headache
Other primary head aches
Secondary headaches causes
Head or neck trauma Vascular disorder CNS Infection Intracranial Pressure disorder Metabolic disorders Drug withdrawal disorders Headache psychiatric disorder Dental, ENT or ocular problem
What examinations and investigations would you do for headache
Full neuro exam Fundoscopy Miningism Systemic exam Temperature Blood pressure
Imaging and tests
CT, MRI
ESR bloods
LP
Red flags for headache
Age of onset middle aged to elderly (>50)
Abrupt and severe onset (thunderclap)
Progressively severe or increasing frequency
Significant change in headache pattern or new headahce
Meningism, focal signs, confusion, altered LOC
Abnormal examnation, fever, weight loss
Posture, valsalvar, coughing exertion
Systemic disease, cancer, HIV, 3rd trimester, pregnancy postpartum, recent head injury
What is the third type of headache classification after primary and secondary
Cranial neuralgias
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What position makes ICP higher
Lying down
What proportion of those with SAH present with acute onset severe headache as the only symptom
1/3 present with acute onset severe headache as the only symptom
5-11% misdiagnosed commonly as migraine
Describe headache onset with SAH
Abrupt, sudden, acute, thunderclap (over seconds or minutes)
What is the sensitivity of SAH on CT scan
At 12hrs- 98%
3 days 80%
1 week 50%
After 3 weeks 0%
Even if done 12 hours from headache onset 2% will have SAH with normal scan.
What else should be done if you expect SAH other than CT scan
LP should be carried out 12 hours from symptom onset for detection of xanthochromia
From 12 hours up to 2 weeks xanthochromia is reliable for the presence of SAH using Spectrophotometry
Other causes of thunderclap headache other than SAH
IC infection:
Meningitis
CSF pressure related:
- 3rd ventricle colloid cyst
- Spontaneous intracranial hypotension
Vascular:
- Ischaemic and haemorrhagic stroke
- Cerebrovenous thrombosis
- Cervical arterial dissection
- Pituitary apoplexy
Acute hypertensive crisis
For what time period is xanthochromia reliable for detecting presence of SAH?
From 12 hrs to 2 weeks!……………
What are the parts of the peripheral vs the central vestibular system
Peripheral:
Semicircle canals
Vestibular nerve
Central:
Brainstem
Cerebellum
Peripheral causes of vertigo
BPPV
Meniere’s
Vestibular Neuritis
Central cuases of vertigo
Would you be worried about isolate nystagmus?
Other CNS deficits
But 4% of isolated nystagmus is caused by stroke
Why is it important to establish whether double vision is horizontal or vertical
Most common causes of horizontal diplopia are VIth nerve palsy and internuclear ophthalmoplegia (in MS).
Horizontal diplopia that appears only after a prolonged near vision is highly pointing towards a convergence insufficiency (most common in patients with Parkinson’s disease).
Vertical diplopia may be a sign of thyroid eye disease, cranial nerve palsy, skew deviation, or Browns syndrome
What would you find on examination of 3rd nerve palsy
- Ptosis (70% of L paplebrae by Parasympathetic III fibres) – may be complete
- Mydriasis with decreased direct and consensual constriction
- Inferio-lateral deviation of eye in primary position
- Diplopia on upwards and inwards gaze
- Loss of accomodation
List the components of the UMN and the LMN
UMN:
Brain
Brain stem
Spinal Cord
LMN:
Lower motor neurone
Neuro-muscular junction
Muscle
Where is the lesion if the eye can look up at the start but then fatigues
Fatigability - myasthenia gravis
This is a problem at the NMJ
What is intra-nuclear opthalmoplegia, and what are the differentials for a young and old patient
Most nystagmuses are biocular unless in a medial pontine stroke, where the unilateral medial longitudinal fasciculus is affected. Patient will present with contralateral internuclear opthalmoplegia (INO). If the right medial longitudinal fasciculus is damaged, and patient is instructed to look to the left, the right eye will not look to the left (fails to adduct) while the left eye has horizontal nystagmus.
This is because the medial longitudinal fasciculus function is for concurrence contraction of medial rectus muscle and lateral rectus muscle on adduction gaze. Any lesion that damages the unilateral medial longitudinal fasciculus can produce INO.
In young patients with bilateral INO, multiple sclerosis is often the cause. In older patients with one-sided lesions a stroke is a distinct possibility. Other causes are possible
NOTE THAT THEY GET HORIZONTAL DIPLOPIA TOO WHEN THEIR EYES DO NOT COORDINATE., BUT ACCOMMODATION IS MAINTAINED
What are the symptoms in horners syndrome
Mild ptosis
Moisis
Anhdrosis
Enophalmos
The forehead is spared in which type of lesion
In the UMN lesion, there is still bihemispheric innovation of of the frontalis muscle
But if LMN then there is one sided paralysis which doesn’‘t spare one side of the face
What is bright on CT scan and what is dark
Bright: Blood Contrast Bone Calcium Metal
Dark:
Aiqr
CSF/H20
Oedema
Intra-cerebral haemorrhage why is it an issue
Pressure of increasing amounts of blood Blood itself (blood is irritating to the brain tissue, causing it to swell)
Causes of intracerebral haemorrhage
Hypertension Rupture of an aneurysm or AVM Haemorrhagic necrosis (eg tumour, infection) Venous outflow obstruction (CVT) Trauma Altered haemostasis
How could infection lead to the appearance of a haemorrhage
Can lead to abscess
Which maneuvre can be used to test for BPPV
Hallpike
