Neurology Flashcards
What is shingles also known as?
Herpes Zoster Infection
What causes shingles?
reactivation of varicella zoster virus
Key risk factors for shingles
increasing age, immunosuppressive conditions, HIV
typical presentation of shingles
acute, unilateral, painful blistering rash
Which dermatomes are commonly affected in shingles
T1- L2
Features of shingles
prodromal period
- 2-3day hx of burning pain over the dermatomes affected
- may have fever, headache, lethargy
Rash
- erythematous, macular rash which becomes vesicular
- demarcated by dermatome and doesnt cross the midline
How is shingles diagnosed?
clinical diagnosis
What are the complications of shingles
- post- herpetic neuralgia
- herpes zoster ophthalmicus
- herpes zoster oticus (Ramsay Hunt syndrome):
What is syncope?
transient loss of consciousness with spontaneous complete recovery
What are the main causes of syncope?
- Reflex mediated (neurally mediated)
- Cardiac (arrhythmias and structural causes)
- Orthostatic (iatrogenic, dementia, volume depletion)
Which investigations should be carried out in syncope?
- ECG (?prolonged QT)
- lying standing BP / tilt table test
- Glucose
- Electrolytes
- FBC
- Underlying illness (CXR, CT, LP, ECHO etc)
Causes of cardiac syncope
arrhythmias - bradycardia / tachycardia structural - valvular - MI - HOCM
What is vasovagal syncope?
triggered by emotion, pain or stress. Often referred to as ‘fainting’
What is subarachnoid haemorrhage?
presence of blood in the subarachnoid space
What are the causes of SAH?
head injury (traumatic SAH) is the most common cause
spontaneous SAH (non-traumatic)
Causes of spontaneous SAH
- Intracranial aneurysm( ruptured ‘berry’ aneurysms)
- Arterial dissection
Which conditions are associated with berry aneurysms?
- Adult Polycystic Kidney Disease
- coarctation of the aorta
Classical presentation of SAH
- Thunderclap headache
- N&V
- Meningism (photophobia, stiff neck)
How can a SAH be confirmed?
CT head
LP if CT Head if negative
Neuro referral
Which findings on an LP are indicative of SAH
xanthochromia (result of RBC breakdown) and normal or raised opening pressure
After SAH is confirmed, which investigations can be carried out to identify a causative pathology?
CT inter-cranial angiogram (vascular lesion e.g aneurysm)
What is Multiple sclerosis?
autoimmune disorder characterised by demyelination in the central nervous system
Who is at higher risk of MS
women ages 20-40 living at higher latitude
How can MS be diagnosed
refer to neuro and bloods to exclude other causes
What are the most common initial presentations of MS
- optic neuritis
- transverse myelitis (inflammation within spinal cord)
- cerebellar sx ( dysmetria, ataxia, vertigo)
sx disseminated in time and space
Which investigations should be carried out for MS?
MRI
What is a venous sinus thrombosis?
occurs when a blood clot forms in the brain’s venous sinuses. This prevents blood from draining out of the brain. As a result, blood cells may break and leak blood into the brain tissues, forming a hemorrhage.
What are the symptoms of venous sinus thrombosis?
- headaches
- n&v
- blurred vision
- LOC
- seizures
How is venous sinus thrombosis diagnosed?
MRI venography
CT venography
What is a Cavernous sinus thrombosis
the formation of a clot within the cavernous sinus
What is the most common cause of CST
infection
Common clinical features of CST
headache, unilateral periorbital oedema, proptosis (eye bulging), photophobia and cranial nerve palsies
Which nerve is most commonly affected in CST
abducens nerve (CN VI)
Complication of CST
Where the cause is infection, thrombosis of the cavernous sinus can rapidly progress to meningitis.
Investigations requested in suspected CST
CT Head/ MRI
FBC
Blood culture
?LP
Which seizures last a few seconds and are associated with a quick recovery
Absence
What may provoke an absence seizure
hyperventilation or stress
Who is most commonly affected by absence seizures?
3-10 years old and girls are affected twice as commonly as boys
Prognosis of absence seizures
good prognosis - most become seizure free in adolescence
Status epilepticus is defined as…
a single seizure lasting >5 minutes OR
>= 2 seizures within a 5-minute period without the person returning to normal between them
Why is the priority in Status epilepticus to terminate seizure activity
can lead to irreversible brain damage
What is a febrile convulsion?
seizures provoked by fever in otherwise normal children
clinical features of febrile convulsion
usually occur early in a viral infection
usually lasting less than 5 minutes
most commonly tonic-clonic
How can a generalise seizure be further classified
Motor- e.g tonic-clonic
Non-motor - e.g absence
Sx of epilepsy
bite their tongue
incontinence of urine
post-ictal phase
Which investigations are ordered following a patients first seizure?
EEG and MRI
What are the guidelines for driving post seizure?
- Generally patients cannot drive for 6 months following a seizure.
- For patients with established epilepsy they must be fit free for 12 months before being able to drive
What is the difference between a generalised and focal seizure?
Focal onset seizures start in one area and can spread across the brain and cause mild or severe symptoms, depending on how the electrical discharges spread. Generalized seizures can start as focal seizures that spread to both sides of the brain.
What happens in tonic-clonic seizure?
Tonic - muscles stiffen - LOC - tongue biting Clonic - rhythmical jerking
What is Bell’s palsy?
Acute, unilateral facial nerve (CN VII) paralysis
- rapid onset ( < 72 hours)
Features of Bell’s palsy
- Lower motor neuron facial nerve : forehead affected
- Post-auricular pain (preceding paralysis)
- Altered taste
- Dry eyes
Facial muscle weakness (unilateral):
- drooping of the eyebrows
- corner of the mouth
- loss of the nasolabial fold
What is the bell’s phenomenon?
The eye can’t be closed- eyeball rotates upwards and outwards
What is the follow-up for bell’s palsy?
If paralysis shows no improvement after 3 week, refer to ENT urgently
What is the prognosis for bell’s palsy?
Full recovery within 3-4 months
What are the two main ascending tracts of the spinal cord and what information do they carry?
Dorsal - fine touch, proprioception, vibration sense
Spinothalamic - pain and temperature
What is the descending tract of the spinal cord called and what does it carry?
corticospinal tract carries motor information
Which signs indicate there is a problem with the spinal cord rather than with the other parts of the nervous system?
often bilateral and asymmetrical
mixed upper and lower motor neuron signs as the spinal cord is part of both the CNS and PNS
- upper signs : increased tone, clonus, hyperreflexia
- lower signs: muscle wasting, flaccid paralysis, reduced reflexes
sphincter involvement (e.g urinary retention/constipation)
autonomic dysfunction indicates lesion is above T6
How to tell where in the spinal cord the problem is
cervical if all 4 limbs affected
thoracic if only lower limbs affected
above C3 if resp difficulties and diaphragm affected
What is Amyotrophic lateral sclerosis
(motor neuron disease)
affects both upper (corticospinal tracts) and lower motor neurons
results in a combination of upper and lower motor neuron signs
What features are seen in neoplastic spinal cord decompression?
back pain, may be worse on coughing or lying down
- lower limb weakness
- sensory loss or numbness
- neuro signs dependent on level of lesion
- -above L1 usually UMN in legs and sensory
- below L1 usually LMN in legs and perianal numbness
Which investigation should be requested following suspected neoplastic spinal cord decompression?
urgent whole MRI spine within 24hrs of presentation
What are the symptoms of diabetic peripheral neuropathy?
Sensory loss:
- Tingling
- Numbness - unable to feel light touch
- Cannot feel pain
- Unable to detect change in temperature
What are the presentations of diabetic foot disease?
- neuropathy: loss of sensation
2. ischaemia: absent foot pulses, reduced ankle-brachial pressure index (ABPI), intermittent claudication