Neurology Flashcards
Clinical presentation of SOC
- Seizures- (common with temporal lobe lesions) aura, cortical sensors are located in the temporal lobes
- Focal neurology and gait disturbance
RIP - Headaches
- Vomiting
- Papilloedema
Neuropsychiatric effects
- Personality (frontal lobe tumours)
- Mental state
- Memory and cognition
Incidental finding on imaging
Imaging for SOL
CT with or without contrast
MRI (usually done with contrast) egfr >30, no allergy to contrast
Diffusion weighted MRI
Contrast- areas of vascularity are more priminent, helpful if tumoru ro infection suspected
What is multi-modal MRI
MR spectroscopy (to assess metabolism)
MR perfusion (to assess vascularity)
How to describe the MRI/CT
Particularly
Interesting
Surgeons
Love
Carefully
Drilling
Massive
Burr
Holes
Patient and imaging technique details
Intra or extra-axial
Shape (irregular,circular)
Location
- Supra or infratentorial
- Lobes/parts of brain involved
Density OR intensity
- Hypo/hyperdense used with CT
- Hypo/hyperintense used with MRI (how white the lesion)
Border
- How defined
- Oedema
Contrast enhancement
- Homogenous/heterogenous
- Rim enhancemnet
Mass effect
- Effacement of sulci; ipsilateral/contralateral
- Midline shift
- Ventricle compression
- Basal cisterns: obliterated/patent
- Hydrocephalus
Differential diagnosis for intracranial mass lesions
Vascular
- Haemorrhage
- Infarct
- Vascular malformation
- Aneurysm
Infection
- Abscess
Neoplastic
- Metastasis
- Primary brain tumours
Cyst
Inflammatory
- Multiple sclerosis
- Granulomatous disease
(Google images of SOL on CT and MRI)
What is the standard investigation within neurology?
Non contrast CT followed by MRI is standard investigation
Aetiology of cord compression
- Trauma
- Prolapsed intervertebral disc
- Atlantoaxial subluxation
- Infection
- Bone metastases
What is paraplegia? (below T1)
Partial or total paralysis in the lower half of the body
Including the legs, feet and toes
What is tetraplegia (above T1)
Severe form of paralysis that affects all four limbs, the trunk, and the pelvic organs
What are red flag symptoms of spinal cord compression
- Weakness
- Paraesthesia
- Ataxia
- Urinary retention
- UMN signs (clonus, hyperreflfexia)
How common is it for herniated lumbar discs to cause spinal cord compression?
2%
Most common location for prolapse
L4/L5 or L5/S1 intervertebral discs
CES-I
Incomplete
Urinary disturbance (reduced urinary sensation
Can’t stream
Loss of desire to void
CES-R
Compression has been significant enough to cause retention
Overflow incontinence
CES requires what for diagnosis
Saddle paraesthesia and impairment of bladder, bowel and sexual function
What are the other symptoms of CES that present more inconsistently
- Loss of lower limb reflexes
- Loss of anal tone
- Lower limb weakness and sensory deficit, which is often asymmetrical
Investigations and management for CE
Emergency MRI of the lumbar spine
Urgent referral to neurosurgical department
Surgical decompression within 48 hours of onset of symptoms
Metastatic disease- radiotherapy
Ankylosing spondylitis- steroids
Infective like discitis- long term antibiotics
Characteristics of true epileptic fits
- Biting the tongue
- Incontinence (but can occur in syncope)
- Eyes open (normally closed in syncope)
- Last around 2-4 minutes
Is epilepsy more common in people with learning disabilities?
Yes
‘Bad epilepsy occurs in bad brains’
Some common causes of learning disabilities where epilepsy is prevalent?
Tuberous sclerosis= epilepsy is about 90%
Fragile X syndrome= epilepsy is about 20%
Down syndrome= epilepsy is about 10%
Fetal alcohol syndrome= epilepsy is about 10%
Difference between seizure and epilepsy?
Seizure is the event
Epilepsy is the disease associated with spontaneously recurring seizures
Causes of seizures that aren’t epilepsy
- Febrile seizures in children aged 6 months to 6 years
- Alcohol withdrawal seizures
- Metabolic seizures (sodium, calcium, magnesium, glucose and oxygen)
- Toxic seizures
- Convulsive syncope
What is juvenile myoclonic epilepsy?
50% start with typical absences
Followed by frequent myoclonic jerks in the first hour after waking
Then generalised tonic-clonic seizures preceded by run of myoclonic jerks
Excellent response to valproate, levetiracetam
Carbamazepine and phenytoin make fits worse
What is Jamais vu?
Oppostive to deja vu
Feeling of unfamiliarity
Typical features of temporal lobe seizures
May occur with or without impairment of consciousness or awareness
An aura occurs in most patients
typically a rising epigastric sensation
also psychic or experiential phenomena, such as dejà vu, jamais vu
less commonly hallucinations (auditory/gustatory/olfactory)
Seizures typically last around one minute
automatisms (e.g. lip smacking/grabbing/plucking) are common
Lamotrigine is first choice drug
Common features of frontal lobe seizures
Head/leg movements, posturing, post-ictal weakness, Jacksonian march
Bizarre
Often noisy
MRI imaging is indicated
What are opercular seizures?
- Affects the ‘lid of the brain’
- Homonculus over the lips and mouth
- Mastication
- Salivation
- Swallowing
- Speech arrest
- Fear
- Epigastric aura (hunger, nausea)
- Gustatory hallucinations (false perceptions of taste, sweet, sour, bitter, salty)
What is Lennox-Gastaut syndrome
- Multiple seizure types- frequent and resistant to treatment
- Tonic seizures during sleep, drop attacks and atypical absences are common
- Usually associated with learning disability
EEG is non-specific
First line- valproate
Second line- lamotrigine
Dravet syndrome
Appears during first year of life
Seizures may be unilateral (hemiclonic) and prolonged
Other seizure types appear including myoclonic and complex partial
Seizures may be precipitated by heat or pyrexia
Development initially normal, then slows
Balance impairment, ataxia
How do you treat Dravet syndrome?
First line- valproate, clobazam
Second line- stiripentol, topiramate
Ketogenic diet and vagus nerve stimulation can be used
Avoid drugs that act on the sodium channels (carbamazepine, phenytoin)
Other such as (gabapentin, pregabalin)
What drugs could provoke abscence status?
Tiagabine and vigabatrin
What drugs can make myoclonic epilepsy worse?
Carbamazepine and phenyotin
What should gabapentin and pregabalin be avoided in?
Abscences and myoclonic jerks worse
If a visual field defect is NOT homonymous, where can it NOT originate from?
Anything after the optic chiasm
(Bitemporal hemianopia)
The optic tract, optic radiations of visual cortex
If a bitemporal hemianopia is present, what questions should you be asking in the history?
- Questions relevant to the endocrine status
Think what is close to the optic chiasm! Pituitary gland (sits just behind the optic chiasm), cavernous sinus.
- Changes in appearance (acromegaly), hat/glove size?
- Any cold intolerance, lack of energy, menorrhagia (hypothyroidism)
- Any lactation (prolactin excess)
- Oligomenorrhoea or amenorrhoea (FSH/LH deficiency)
- Any weight gain, abdominal striae (ACTH excess)
What can cause an altitudinal field defect (affects upper and lower)
Retinal or optic nerve disease
(Think about GCA)
Four common causes of unequal pupils
- 3rd nerve palsy
- Horner’s syndrome
- Tonic pupil
- Pharmacological pupil
What is the main difference between monocular and binocular double vision?
Monocular is mainly an optical problem
Binocular is neurological
Sign of congenital horner’s syndrome?
Loss of sympathetic innervation
Which stimulates melanocytes
Paler pigment
Is pupil dilation sympathetic or parasympathetic?
Sympathetic
Fight or flight- need to allow more light to get into the eyes
Improving vision and awareness
Why do your pupils dilate when you see something you love or find exciting?
- Positive emotions stimulate the sympathetic nervous system ‘similar to fight or flight’
- Pay more attention
- Non-verbal social sign, potentially making someone appear more appealing to others
Basic algorithm for seizure management
A-E
IV Lorazepam 4mg
Wait 10-15 minutes
IV Lorazepam 4mg
Once established status
Phenytoin infusion 20mg/kg-max rate 50mg/min
Call ITU (patient is not oxygenating while they are seizing- risk of hypoxic brain injury)
Rapid sequence induction-Thiopental
What to do when the seizure terminates
- Close monitoring
- Await blood results
- Investigate underlying cause
- Pabrinex (alcoholism)
- Collateral history
- CT head, blood cultures, blood alcohol level, examine for meningism, LP?
- Contact neurology in morning if remains stable
Definition of a stroke
Clinical syndrome consisting of rapidly developing clinical signs of focal or global disturbance of cerebral function
Lasting more than 24 hours
OR lreading to death
Investigations for stroke in all patients
- CT (to see whether it is hemorrhagic or not) or MRI
- ECG
- FBC, PT, INR, APTT
- Electrolytes, blood glucose
- CRP
- LFTs, Us&Es
How do you manage a hemorrhagic stroke
Neuro intensive care unit
Definition of status epilepticus?
A medical emergency where a person has a seizure lasting longer than 5 minutes or mul
Refractory status epilepticus
Persisting despite administration of at least 2 appropriately medications
Super refractory status epilepticus
Continues for more than 24 hours
Prolonged super refractory status epilepticus
Persists more than 7 days
NORSE
New onset refractory status epilepticus
No history of prior epilepsy
FIRES
Febrile infection related epilepsy syndrome (category of NORSE)
Requires a febrile infection between two weeks and 24-hr prior to the start of refractory status epilepticus
Causes of NORSE
- Infection
- Cryptogenic
- Autoimmune
- FIRES
- Super-refractory status epileptics of unknown cause
After what time frame of status epilepticus will it become life threatening?
30 minutes of a continuous seizure
After this time- we have to completely anesthetize this patient
Intubate the patient, take to ITU for continuous EEG monitoring
Difference between seizure, epilepsy and status epilepticus
Seizure= a single episode of abnormal brain activity
Epilepsy= a long-term condition with recurrent, unprovoked seizures
Status epilepticus= A prolonged seizure (more than 5 minutes) requiring urgent medical attention
Initial medical treatment in status epilepticus
- Levertiracetam is started at the same time Lorazepam is
How to assess bulbar reflex
Cough
How to assess diaphgram
Sniff reflex
Triggers of GBS
Infections- Campylobacter, CMV, Zika, HIV, COVID, influenza A and B
Vaccination
Surgery
Trauma
Medications- Isotretinoin, Tacrolimus
Simply explain the pathogenesis of GBS
Immune system triggered by infection
- Infection from campylobacter
- Triggers the immune system to produce antibodies to fight the pathogens
Molecular mimicry
- Bacterial/viral proteins share similarities with proteins on nerve cells
- Immune system mistakenly attacks the body’s own nerve cells
Nerve damage and symptoms
- The immune system attacks the myelin
- Muscle weakness, numbness and paralysis
Features needed for diagnosis of Guillain-Barre syndrome in clinical practice
Progressive weakness in legs and arms
Areflexia
Progressive phase lasts days to 4 weeks
Relative symmetry
Mild sensory symptoms or signs
Cranial nerve involvement (bilateral weakness of facial muscles)
Pain (common)
IF there is bowel/bladder dysfunction- more likely spinal cord. GBS is peripheral nerves
Explain simply what albuminocytogenic dissociation is?
When there is elevated albumin in the CSF while white blood cells are normal
Sign of disruption of blood-brain barrier (inflammation/infection) allows larger molecules to cross into the CSF
What is a myasthenic gravis crisis?
Myasthenic crisis is a complication of myasthenia gravis characterized by worsening of muscle weakness, resulting in respiratory failure that requires intubation and mechanical ventilation.
Features of myasthenia gravis?
The key feature of weakness in patients with myasthenia gravis is fatigability.
Patients with myasthenia gravis commonly present with:
Fatiguable limb muscle weakness
Ptosis
Diplopia
Facial palsy
Bulbar weakness e.g. dysphagia, dysphonia
Proximal muscle weakness
ICE pack test for myasthenia
> 2mm improvement in ptosis- patient has myasthenia gravis
Cold temperatures- acetylcholinesterase enzyme reduces
Specific test for myasthenia gravis
Single fibre EMG will show increased jitter
Treatment for drug-resistant MG
Rituximab
Cyclophosphamide
Tacrolimus
Difference between encephalitis and meningitis
Encephalitis
- Person of any age, at any time of the year which an acute onset of fever and either a change in mental status (confusion, disorientation, coma or inability to talk)
Or new onset of seizure
Meningitis
- Patient with a history of fever and one of the following signs: neck stiffness, altered consciousness or other meningeal signs
What is jolt accentuation of headache with meningeal irritaiton?
Patient rotates his/her head horizontally two to three times per second.
The test is positive if the patient reports exacerbation of his/her headache with this maneuver.
Jerking with syncope
Not a seizure
- Not symmetrical
- Floppy jerking
- Eyes roll back
- Often make a lot of noise
Processes instantly after
Tonic/clonic
Tonic- all muscles tighten really quickly- diaphragm tightens and a cry is let out
Clonic- jerking
Clench teeth- snorting, foaming at the mouth, biting tongue
After people won’t remember who they are, where they are, wake up on a different planet
What skeletal muscle groups can myasthenia gravis affect?
Extraocular muscles – commonest presentation
Bulbar involvement – dysphagia, dysphonia, dysarthria
Limb weakness – proximal symmetric
Respiratory muscle involvement
What is bulbar palsy?
Tongue - weak and wasted and sits in the mouth with fasciculations. Drooling - as saliva collects in the mouth and the patient is unable to swallow (dysphagia). Absent palatal movements. Dysphonia - a rasping tone due to vocal cord paralysis; a nasal tone if bilateral palatal paralysis.
Combination of bulbar and ptosis?
Myasthenia until proven otherwise
Why is it not brainstem? Wouldn’t be able to do anything- absolutely bed bound
What can myasthenia gravis be precipitated by?
Emotional stress
Pregnancy
Menses
Secondary illness
Thyroid dysfunction
Trauma
Temperature extremes
Hypokalemia
Drugs
Surgery
Tensilon test
Acetylcholine receptor inhibitor
See whether it improves the condition
Have to have a cardiac monitor on- can cause asystole
Characteristics of myasthenic crisis and how a cholinergic crisis differs
Slack facial muscles
Weak neck- can be resting their head on their breastbone
Drooling
Nasal speech
Generally weak
Unsafe swallow
Cholinergic crisis
Looks similar to myasthenic crisis.
Excess of acetylcholinesterase inhibitors
excessive stimulation of striated muscle - flaccid paralysis
Respiratory failure
Miosis and the SSLUDGE syndrome
(ie, salivation, sweating, lacrimation, urinary incontinence, diarrhea, GI upset and hypermotility, emesis) also may mark cholinergic crisis-not inevitably present
Complications of myasthenia gravis
Respiratory
Respiratory failure
Aspiration
Respiratory infection
DVT
Thromboprophylaxis
Therapeutic management of myasthenia gravis
Anticholinesterase inhibitors-
Pyridostigmine- people can take too many of these because they feel so good! Can lead to a cholinergic crisis
Onset 30min; peak 60-120min; duration 3-6hr (need to know this!! Affects swallowing you need to make sure they are given this before they eat!! at peak time, not when the tablet is wearing off
Neostigmine (ITU)
Corticosteroids
Start low – high dose may paradoxically worsen symptoms
Azathioprine
Steroid sparing
IV immunoglobulin
Acute decline or crisis – 60% will respond after 7-10 days
Plasmapheresis- removes AChR antibodies ->short-term improvement
Similar efficacy to IV Ig
Early management of myasthenia gravis
Supportive measures
Bedside spirometry
FVC (anything else is not sensitive enough) don’t do sats, ABG
If falling or FVC< 18-20ml/kg review as may need ventilation
Blood gases ↑CO2 ↓O2 acidosis late manifestations of type II respiratory failure
No problem with gas exchange- need power! Can’t move air in and out
Different subtypes of GBS
AIDP – acute inflammatory demyelinating polyradiculoneuropathy – commonest 95% (better recovery)
AMAN – acute motor axonal neuropathy
AMSAN – acute motor and sensory axonal neuropathy
Acute pandysautonomia- every time they move their head, blood pressure drops and can’t get out of bed
Axonal- a lot more difficult to regenerate.
Overlap – Miller Fisher (sensory ataxia, arreflexia, opthalmoplegia)
Guillain-Barre pathophsiology
1 to 3 weeks after immune system stimulation:
URTI or GI infection
Also: trauma, surgery, vaccination, pregnancy, other
Cross-reaction with schwann cell/ (axolemma) antigens
T-cell sensitization damaging
Myelin
(Axon)
Impaired neurotransmission to the periphery
Diagnostic criteria for ‘typical’ GBS
Symmetrical length dependent neuropathy (affects the longest nerves first)
Might get ileus- loss of bladder control
Required features:
Progressive weakness in both arms and legs
Areflexia (or hyporeflexia)
Features supportive of diagnosis
Progression of symptoms over days to 4 weeks
Relatively symmetric
Mild sensory signs or symptoms
CN involvement, especially bilateral facial weakness
Recovery begins 2-4 weeks after progression ceases
Autonomic dysfunction
Absence of fever at onset
Typical CSF and EMG/NCS- nerve conduction studies features. Everything might be normal in the first weeks
Don’t let a little detail put you off a diagnosis
Diagnostic studies for GBS
EMG/ NCS
CSF
↑protein, N/ mild lymphocytes
Increase in protein takes 1-2 weeks to develop
Consider serology
Campylobacter if GI upset
CMV, EBV,HSV,HIV, mycoplasma
Stool cultures
Throat swab
Anti-ganglioside antibodies
AMAN – anti GM1, C Jejuni
MF – anti GQ1B
Complications
- Pain- natural spinal curvatures are starting to sag, MSK pain
- DVT/PE
- SIADH (forget)
- Renal failure
- Hypercalcaemia
How to generally manage GBS
Close observation as weakness is progressive- can change in the day! riding bike in the morning, ventilator in the evening
Bedside spirometry
Ventilatory support
ECG +/- cardiac monitoring
Nutritional support +/- NG tube
DVT prophylaxis
May need urinary catheter
Laxatives and bowel care
Pain control
Severe GBS management
IV immunoglobin
Plasmapheresis used within the first 2 weeks of onset. After three weeks, plasmapharesis no benefit
NB steroids not effective
What is the complete recovery at 1 year?
70%
Not guaranteeing everything but most people do
When should you call an ambulance with a seizure?
- Known first tonic-clonic seizure
- Lasts more than 5 minutes
- One tonic-clonic seizure after another without gaining consciousness
- Person becomes injured during the seizure
- Trouble breathing after their seizur3
How does Lorazepam work in a seizure?
Lorazepam is a benzodiazepine, a class of drugs that enhances the effect of GABA (a major inhibitory neurotransmitter in the brain).
GABA binds to its receptors and slows down or reduces the activity of nerve cells (neurons).
During a seizure, there is excessive neuronal firing, leading to
uncontrolled brain activity.
Lorazepam increases GABA’s effect, which inhibits the overactive neurons.
This calms the brain’s electrical activity, helping to stop or prevent the seizure.
How long do tonic-clonic seizures normally last for?
1-3 minutes
What is an EMG?
An Electromyography (EMG) is a test that checks how well your muscles and the nerves that control them are working. It measures the tiny electrical signals your muscles make when they are active and when they are resting.
What is functional overlay?
Functional symptoms are real, physical symptoms that cannot be explained by structural damage or a specific disease. They are often associated with stress, anxiety, or emotional factors.
How often are MDTs for stroke?
5 days a week
What do you have to measure in the blood before you give Azathioprine?
TMPT
Breaks down thioprine drugs
Can cause
Bone Marrow Suppression (Myelosuppression): The most severe side effect. It can result in:
Leukopenia (low white blood cells), increasing the risk of infections.
Thrombocytopenia (low platelets), leading to increased bleeding risk.
Anemia (low red blood cells), causing fatigue and weakness.
Severe Toxicity: Patients with very low or absent TPMT activity can experience life-threatening toxicity after standard doses of azathioprine, including severe infections or bleeding due to bone marrow failure.
What is spinocerebellar ataxia and what is it’s inheritance pattern?
Definition: SCA refers to a group of inherited genetic disorders that cause progressive ataxia (loss of coordination and balance) due to the degeneration of the cerebellum (the part of the brain that controls movement) and sometimes the spinal cord or other parts of the brain.
Symptoms:
Difficulty with balance and coordination.
Unsteady walking (gait).
Trouble with fine motor tasks (writing, buttoning clothes).
Slurred speech.
Eye movement abnormalities.
In more severe cases, swallowing and speech can also be affected.
Autosomal dominant
What FVC would warrant ITU and what FVC is normal for myasthenia gravis patients?
<1= ITU
> 2 is normal