Neurology Flashcards
Subdural haematoma lies in which space?
Between dura mater and arachnoid mater.
Why do subdural haematomas occur?
Stretching of bridging veins makes them vulnerable to tearing.
How do subdural haematoma present?
Gradual deterioration in cognitive function - pstients often present with confusion if chronic.
Subdural haematoma are more likely to occur in which groups?
- Elderly.
- Dementia.
- Alcoholics.
- i.e. conditions associated with brain shrinkage.
Dura mater composed of how many layers?
Two - outer endosteal and inner meningeal.
What is enclosed within the two layers of the dura mater?
Venous sinuses.
Name the four fibrous flanges/ septae which minimise rotatory displacement of the brain.
- Falx cerebri.
- Falx cerebelli.
- Tentorium cerebelli.
- Diaphragm sellae.
These are formed from the inner meningeal layer of dura mater.
Extradural haematoma occurs where?
Between endosteal layer of dura mater and the skull.
Extradural haematoma occurs typically due to bleeding of which artery?
Middle meningeal artery.
- Comonly in pterion region.
Subarachnoid haematoma occurs where?
In subarachnoid space i.e. between pia and arachnoid.
Where do subarachnoid haematoma typically originate?
Circle of Willis region - blood causes CSF contamination on LP.
Where do intracerebral bleeds occur?
Within brain parenchyma.
Dura mater is richly innervated. True or false?
True - dural stretch causes pain typically perceived as headache (e.g. meningitis, post-dural - LP or epidural).
Differential for acute headache?
TICOS
Trauma. Infection (meningitis, encephalitis). Cerebrovascular (SAH, intracranial haemorrhage/infarction). Ocular (glaucoma). Sinusitis.
What is pituitary apoplexy?
Bleeding or impaired blood supply to pituitary gland.
How does pituitary apoplexy present?
Sudden onset headache.
Shock - pituitary failure causing adrenal crises.
Likely diagnosis and responsible autoantibodies?
In the morning the patient is well and there is no weakness.
As the day progresses he experiences weakness and tiredness, double vision + drooping eyelids + difficulty speaking / chewing / swallowing. He also experiences muscle weakness after exercise which is relieved by resting.
OE there is no muscle fasciculation, muscle atrophy or muscle spasticity. His sensation is normal as are all his reflexes. Pupils are equal and reactive to light.
Myasthenia gravis and acetylcholine receptors.
What is myasthenia gravis?
Autoimmune disease of neuromuscular junction - acetylcholine receptor antibody presence at post-synaptic membrane.
Symptoms of myasthenia gravis?
- Diplopia.
- Dysphagia.
- Dysarthria.
- Electromyography will show decreased muscle contraction upon repetitive stimulation.
+ usually positive for acetylcholine receptor antibodies.
- Normal pupils.
- Normal reflexes.
- Normal sensation.
Management of myasthenia gravis?
Neostigmine.
Pyridostigmine.
Which antibodies play a role in multiple sclerosis?
Antibodies to myelin.
GCS criteria for eyes?
4 - eyes open spontaneously.
3 - eyes open to speech.
2 - eyes open to pain.
1 - eye do not open.
GCS criteria for verbal?
5 - orientated. 4 - confused. 3 - inappropriate words. 2 - inappropriate sounds. 1 - no verbal response.
GCS criteria for motor?
6 - obeys commands.
5 - localises pain.
4 - withdraws from pain.
3 - abnormal flexion to painful stimuli (decorticate).
2 - extension to painful stimuli (decerebrate).
1 - no movement.
A GCS below which score is indicative of the need for airway protection?
GCS of 8 or below. Patients unable to protect their own airway - usually require intubation.
