Neuro Flashcards
What is the definition of a TIA?
temporary neurological dysfunction lasting less than 24 hours cuased by ischaemia but without infarction
What are crescendo TIAs
two or more TIAs within a week -> high risk of stroke
What risk factors increase the risk of stroke in patients taking the COCP?
COCP +:
migraine with aura
smoker over 34
history of stroke or TIA
How do you manage a stroke initially?
Exclude hypoglycasemia
Non-contrast CT head - exclude haemorrhage
Aspirin 300mg daily if not haemorrhage
Admit to specialist stroke centre
Alteplase - thrombolyse
When should alteplase be given in strokes?
within 4.5 hours of symptom onset
What conditions should patients be investigated for if they have a TIA or stroke?
Carotid artery stenosis - carotid ultrasound
Atrial fibrillation - ECG / holter monitoring
What shape are subdural bleeds?
crescent shape
What shape are extradural bleeds?
bi-concave shape
What usually causes an extradural haemorrhage?
Middle meningeal artery rupture in temporoparietal region associated with fracture of temporal bone
Which types of haemorrhage have a lucid period?
Extradural haemorrhage
What are the surgical options for extradural or subdural haematomas?
Craniotomy - open removal of section of the skull
Burr holes - to drain the blood
What is the mortality of a SAH?
30%
Which conditions is SAH common in?
Sickle celll
Marfan’s / Ehlers Danlos
Neurofibromatosis
AD Polycystic kidney disease
At what time frame is a CT less reliable for a SAH?
More than 6 hours after the start of symptoms
When may a lumbar puncture be performed for a SAH diagnosis after a normal CT head?
Wait at least 12 hours after onset of symptoms - it takes time for bilirubin to accumulate in CSF
What does a positive CSF sample show in SAH?
Raised RCC
Xanthochromia - caused by bilirubin
What is gold standard diagnostic tool to confirm diagnosis of SAH?
CT angiography
What is the treatment/management of a SAH?
endovascular coiling by an interventional neuroradiologist or neurosurgeon
Platinum coils are used
What prevents vasospasm in SAH and what class of drug is it?
Nimodipine - a calcium channel blocker
What is a severe complication of SAH?
Hydrocephalus
How may hydrocephalus be managed post-SAH?
Lumbar puncture
External ventricular drain
Ventriculoperitoneal shunt
Which neuronal cells provide myelin in the CNS?
Oligodendrocytes
Which neuronal cells provide myelin in the PNS?
Schwann cells
Which cells does multiple sclerosis affect?
Oligodendrocytes in the CNS
What are lesions in MS described as?
Disseminated in time and space
What is Oscillopsia?
This is the visual sensation of the environment moving and being unable to create a stable image
Eye movement abnormalities can be caused by lesions affecting whihc cranial nerves?
Oculomotor (III)
Trochlear (IV)
Abducens (VI)
Where is the lesion if the patient has internuclear ophthalmoplegia
Medial longitudinal fasciculus
What does the medial longitudinal fasciculus connect?
The cranial nerve nuclei that conctrol eye movements - 3,5,6
Where is the lesion if the patient has a conjugate (connected) lateral gaze disorder - both eyes look laterally to the left or right
Abducens nerve (VI)
What focal weakness symptoms may MS present with?
Incontinence
Horner syndrome
Facial nerve palsy
Limb paralysis
What focal sensory symptoms may MS present wiht?
Trigeminal neuralgia
Numbness
Paraesthesia
Lhermitte’s sign
What is Lhermitte’s sign
an electric shock sensation that travels down the spine and into the limbs when flexing the neck
What does Lhermitte’s sign indicate
MS disease in the cervical spinal cord in the dorsal column
It is caused by stretching the demyelinated dorsal column
What does sensory ataxia refer to?
It is due to the loss of proprioception and the inability to sense the position of the joint - Positive Romberg’s
It can also cause pseudoathetosis
What is pseudoathetosis
Involuntary writhing movements
Where is the lesion if the patient has sensory ataxia
Dorsal columns of the spine
What condition is associated with muscle weaknes and diminished response to repetitive stimulation on EMG?
Myasthenia gravis
What is the first-line drug for ocular myasthenia gravis?
Pyridostigmine
What is first-line management for focal seizures?
Lamotrigine
Levetiracetam
When can extended target time of 24hrs for thrombectomy be considered?
If there is the potential to salvage brain tissue, as shown by imaging such as CT perfusion or diffusion-weighted MRI sequences showing limited infarct core volume
What is lateral medullary symptoms?
Left posterior inferior cerebellar artery infarction
PICA lesion
Cerebellar signs
Contralateral sensory loss
Ipsilateral Horner’s
What are the signs of a posterior cerebral artery stroke?
Contralateral homonymous hemianopia with macular sparing and visual agnosia
What nerve damage is common in a mid shaft humeral fracture and what is the presenting sign?
Radial nerve
–> Wrist drop
Which cranial nerve is susceptible to damage early in the course of raised ICP?
Abducens nerve
Due to its long intracranial course
Damage to which nerve results in RAPD?
Optic nerve
What is syringomyelia
Dilatation of CSF space within the spinal cord
What is the sensory loss distribution in syringomyelia?
Dissociative loss of sensation of pain, temperature and non-discriminative touch
In a cape-like distribution
What nerve palsy causes “vision worse going down the stairs”
4th nerve palsy = trochlear nerve
What medication is used to treat Idiopathic intracranial hypertension
Acetazolamide
Carbonic anhydrase inhibitor
What is prescribed in absence seizures?
Ethosuximide
What are tongue fasciculations a sign of
bulbar onset motor neurone disease
What is the classic triad of normal pressure hydrocephalus
Dementia
Ataxia
Urinary incontinence
What diet is useful in epilepsy non-responsive to medications?
Ketogenic diet
Which nerve is affected if a patient cannot abduct their left eye?
CN 6 = abducens nerve
Which muscles are typically spared in MND?
Ocular msucles
What can be found in the CSF of patients with MS?
Oligoclonal bodies / bands
Chronic haemorrhage is hypo or hyperdense?
Hypodense
What would a CT head showing infective picture and temporal lobe changes (low-density enhancement in the anterior and medial aspects) suggest?
Herpes simplex encephalitis
What is autonomic dysreflexia?
T4-level spinal cord injury, bradycardia, flushing, severe hypertension, and sweating above the lesion strongly indicates this condition
What is lambert-eaton syndrome
paraneoplastic myasthenic syndrome - caused by small cell lung cancer
What are the features of Lambert-Eaton syndrome?
long-standing cough
SOB
Autonomic symptoms
Limb-girdle weakness -> waddling gait
Hyporeflexia
What meds can be used for spasticity in MS
Baclofen
Gabapentin
What drug is used for long-term prophylaxis of cluster headaches
verapamil
What sign can be used to diagnose degenrative cerivcal myelopathy
Hoffman’s sign
If a patient has chronic subdural haematoma, will the CT appear hypodense or hyperdense?
Hypodense (dark)
