Neurology Flashcards
What is the diagnostic criteria for medication overuse headache?
- Headache present for >15 days/month.
- Regular use for >3 months of >1 symptomatic treatment drugs.
- Headache has developed or markedly worsened during drug use.
What features might be present in the history of a headache that make you suspect meningitis?
- Pyrexia.
- Photophobia.
- Neck stiffness.
- Non-blanching purpura rash.
What muscle is essential for correcting the extorsion action of lateral rectus when walking downstairs?
Super oblique (Cn 4 innervation).
What muscle needs to be working in order to test the action of superior and inferior rectus?
Lateral rectus.
To test superior and inferior rectus the patient is asked to abduct their eye 30 degrees first, this requires lateral rectus.
Superior and inferior oblique can never have isolated action. How can they be tested?
Position the eye so that superior and inferior recti are giving maximal rotation and look for complete correction.
Give 4 symptoms of rabies.
- Fever.
- Anxiety.
- Confusion.
- Hydrophobia.
- Hyperactivity.
Name the organism responsible for causing tetanus.
Clostridium tetani (gram positive anaerobe).
It infects via dirty wounds.
Give 3 symptoms of tetanus.
- Trismus (lockjaw).
- Sustained muscle contraction.
- Facial muscle involvement.
Name the organism responsible for causing botulism.
Clostridium botulinum.
Give 3 symptoms of botulism.
- Diplopia (double vision).
- Dysphagia.
- Peripheral weakness.
If a patient has aphasia what region in the brain has been affected?
Broca’s area.
If a patient has receptive dysphasia what region in the brain has been affected?
Wernicke’s area.
How does carbamazepine work as an AED?
It inhibits pre-synaptic Na+ channels and so prevents axonal firing.
What can be the affect of non missile trauma to the scalp?
Contusions and lacerations.
What can be the affect of non missile trauma to the skull?
Fracture.
Give 2 risks associated with skull fracture.
- Haematoma.
2. Infection.
What can be the affect of non missile trauma to the meninges?
Haemorrhage and infection (due to skull fracture).
What can be the affect of non missile trauma to the brain?
Contusions, lacerations, haemorrhage and infection (due to skull fracture).
Describe the aetiology of diffuse traumatic axonal injury.
Acceleration/deceleration -> shearing rotational forces -> axons tear.
Give a sign of diffuse vascular injury due to non missile trauma.
Multiple petechial haemorrhages.
What is more severe: diffuse traumatic axonal injury or diffuse vascular injury?
Diffuse vascular injury is MUCH more severe. It can result in near immediate death.
Describe the mechanism behind acceleration/deceleration damage.
A force to the head can cause differential brain movements -> shearing, traction and compressive stresses -> risk of axon tear and blood vessel damage.
What is contusion?
Superficial ‘bruises’ of the brain.
What is laceration?
When a contusion is severe enough to tear the pia mater.
What is the cause of chronic traumatic encephalopathy?
Often seen following repetitive mild traumatic brain injury.
Give 3 initial symptoms of chronic traumatic encephalopathy.
- Irritable.
- Impulsive.
- Aggressive.
- Depressed.
Give 3 later symptoms of chronic traumatic encephalopathy.
- Dementia.
- Gait and speech problems.
- PD symptoms.
Give 3 signs of chronic traumatic encephalopathy.
- Atrophy of deep brain structures.
- Enlarged ventricles.
- Tau deposited in sulci.
You see a patient who you suspect has meningitis. It is noted that they have raised ICP. Would you do a lumbar puncture?
NO! You would not do a lumbar puncture in someone with raised ICP due to the risk of coning.
Give 4 signs of raised intra-cranial pressure.
- Papilloedema.
- Focal neurological signs.
- Loss of consciousness.
- New onset seizures.
What drug is prescribed in sub-arachnoid haematoma to prevent arterial spasm and subsequent ischaemia? What class of drugs does this come from?
Nimodipine – CCB.
Give 3 differences in the presentation of a patient with a subdural haemorrhage in comparison to an extradural haemorrhage.
- Time frame: extra-dural symptoms are more acute.
- GCS: sub-dural GCS will fluctuate whereas GCS will drop suddenly in someone with an extra-dural haematoma.
- CT: extra-dural haematoma will have a rounder more contained appearance.
What are the 3 cardinal presenting symptoms of brain tumours?
- Raised ICP.
- Progressive neurological deficit.
- Epilepsy.
Give 3 symptoms of raised ICP.
- Headache.
- Drowsiness.
- +/- vomiting.
You ask a patient with a brain tumour about any factors that aggravate their headache. What might they say?
- Worst first thing in the morning.
2. Worst when coughing, straining or bending forward.
What is the cardinal physical sign of raised ICP?
Papilloedema.
Due to obstruction of venous return from the retina.