Neuro conditions 1 Flashcards
What are the causes of bloackout?
Syncopy First seizure Hypoxic seizure Concussive seizure Cardiac arrhythmia Non-epileptic attack (narcolepsy, movement disorder, migraine
What are the important considerations in a blackout?
What were they doing at the time?
What, if any, warning feelings did they get? - aura
What were they doing the night before?
Have they had anything similar in the past?
How did they feel afterwards?
Any injury, tongue biting or incontinence?
Also get witnesses during + before attack
What is syncope?
Vasovagal syncope is the most common cause of fainting Prodrome: Light-headed, nausea Hot, sweating Tinnitus Tunnel vision
What are the triggers for vasovagal syncope?
Prolonged standing Standing up quickly Trauma Venepuncture Watching/experiencing medical procedures Micturition Coughing
What are the differences between syncope and seizure?
Seizure is a loss of control that can happen in any posture with sudden onset
Often associated with incontinence pallor and injury
Syncope is a loss of consciousness that happens in an upright posture with gradual onset
>Precipitants are common with rapid recovery
What are hypoxic seizures?
When kept upright in a faint
Can occur in aircraft, dentist, helped to feet etc
May have succession of collapses
Seizure-like activity may occur
What are non-epileptic attacks?
Commoner in women than men Can be frequent May look bizarre Can be prolonged May have a history of other medically unexplained symptoms May have history of abuse May superficially resemble a generalised tonic-clonic seizure May resemble a “swoon” May involve bizarre movements
How do you investigate first seizure?
Blood sugar
ECG
Consideration of alcohol and drugs
CT head (see criteria)
What is the advice for driving after seizure?
Give safety information
Inform employer
Driving regs - After 6 months if normal investigations, if abnormal/alcohol related 12 months (for both, no recurrent fits)
What features suggest epilepsy?
History of myoclonic jerks, especially first thing in morning, absences or feeling strange with flickering lights
– in keeping with a primary generalised epilepsy
History of “deja vu”, rising sensation from abdomen, episodes where look blank with lip-smacking, fiddling with clothes – suggest a focal onset epilepsy
What is epilepsy?
Condition in which seizures recur, usually spontaneously
What is a seizure?
Seizure - intermittent disturbance of consciousness, behaviour, emotion, motor function or sensation
What are focal seizures?
Characterised via aura, motor features, autonomic features + degree of awareness/responsiveness
May involve generalised convulsive siezure
How do you investigate seizures?
EEG for primary generalised epilepsies including hyperventilation and photic stimulation: sometimes sleep deprivation
MRI for patients under age 50 with possible focal onset seizures: CT usually adequate to exclude serious causes over this age
Video-telemetry if uncertainty about diagnosis
What are the features of a primary generalised seizure?
No warning Often below 25 May have history of absences + myoclonic jerks Generalised abnormality on EEG May have family history
What are the features of a focal/partial seizure?
May get aura Any age - cause can be any abnormality Simple partial + complex partial can become secondarily generalised Focal abnormality on EEG MRI may show cause
What are the first line treatments for primary generalised epilepsy?
Sodium Valproate, Lamotrigine, Levetiracetam
What are the first line treatments for partial or secondary generalised seizures?
Lamotrigine or Carbamazepine
What is the first line treatment for absence seizures?
Ethosuximide
What are the side effects of sodium valproate?
tremor, weight gain, ataxia, nausea, drowsiness, transient hair loss, pancreatitis, hepatitis
What are the side effects of carbamezepine?
ataxia, drowsiness, nystagmus, blurred vision, low serum sodium levels, skin rash.
What is status epilepticus?
Prolonged or recurrent tonic-clonic seizures persisting for 30 minutes + with no recovery period between seizures
Usually in patients with no previous history of epilepsy
Mortality 5-10%
How do you treat status epilepticus?
Midazolam:
Lorazepam:
Diazepam
What are the symptoms of muscle disorders?
Weakness of skeletal muscle Short of breathe (respiratory muscles) Cardiomyopathy Poor suck/ feeding/FTT(failure to thrive)/floppy Cramp, pain (no ATP) Myoglobinuria (black urine)
What are the signs of muscle disorders?
Wasting/ hypertrophy
Normal or reduced tone and reflexes
Motor weakness…NOT sensory
What are the investigations into muscle diseases?
History + exam (history important)
CK (creatin kinase)
Muscle biopsies (less +less)
Genetic testing
What are the types of muscle diseases?
Muscular dystrophies Channelopathies (problem with channels) Metabolic muscle disease Inflammatory muscle disease Congenital myopathies
What are muscular dystrophies?
Mostly due to one defective gene
Cause structural problems in muscles
What are channelopathies?
Disorders of Ca, Na and Cl channels
What are the metabolic muscle diseases?
Disorders of carbohydrate metabolism
First 10 mins difficult, if overcome have stores
Disorders of lipid metabolism - unable to last past 10 minutes
Mitochondrial myopathies/ cytopathies
What is inflammatory muscle disease?
Polymyositis Dermatomyositis >Distinctive rash - heliotrophic >Red over elbows, purple on face Acute or subacute Painful weak muscles Any age Other symptoms may be involved (arthritis? Interstitial pneumonia both possible)
What is myasthenia gravis?
Fatiguable weakness: Limbs Eyelids (ptosis) Muscles of mastication (chewing) Talking SOB diplopia
Why does myasthenia gravis happen?
Due to Anti ACHR ab binding to AcH receptor, preventing contraction
how do you investigate suspected myasthenia gravis?
AChR ab
Anti MuSK ab
EMG
Tensilon test (unusual these days as dangerous)
CT chest
>Can be associated with malignant thymoma - always CT to check!!
>Can be caused by it in females under 40, although not always
How do you treat myasthenia gravis?
Symptomatic - Acetylcholinesterase inhibitor
Immunosuppression
Prednisolone
Steroid saving agent (azathioprine)
What can cause generalised peripheral neuropathy?
Metabolic: DM, alcohol, B12 Toxic: drugs Hereditary Infectious: HIV, leprosy Malignancy: paraneoplastic Inflammatory demyelinating Acute = Guillain Barre syndrome Chronic= CIDP
What are the symptoms of a nerve root being affecteD?
Myotomal wasting and weakness
Reflex change
Dermatomal sensory change
What are the symptoms of an individual nerve bein affected?
Wasting and weakness of innervated muscle
Specific sensory change
What are the symptoms of generalised peripheral neuropathy?
Sensory and motor symptoms starting distally and moving proximally
How do you investigate nerve disorders
Blood tests Genetic analysis NCS/EMG Lumbar puncture (CSF analysis) Nerve biopsy (nb sensory nerve)
What is amyotrophic lateral sclerosis?
Usually limb onset, later bulbar and respiratory involvement
combination of UMN and LMN signs
> LMN= muscle fasciculations, wasting, weakness
>UMN= increased tone, brisk reflexes
M:F 3:2
What is the prognosis of ALS?
3-5 years from symptom onset
2-3 years from diagnosis
50% die within 14 months of diagnosis
Mostly supportive treatment
What is myelopathy?
Pathology of spinal cord
What is myelitis?
Inflammation of spinal cord
What is radiculopathy?
Pathology of nerve root
What is radiculitis?
Inflammation of nerve root
What is myeloradiculopathy?
Pathology of spinal cord leading to pathology of nerve root
What are upper motor signs?
No wasting
↑tone
Spascisity
↑reflexes
Pyramidal pattern of weakness - in arms, flexors stronger than extensors, opposite in klegs
What are lower motor neuron signs?
↓tone
↓reflexes
weakness
What is brown-sequard syndrome?
One side loss of motor + touch on one side, temperature on the other
What are the signs of B12 deficient myelopathy?
Paraesthesia hands and feet, areflexia First UMN sign ↑plantars Degeneration of corticospinal tracts→paraplegia Dorsal columns→sensory ataxia Painless retention of urine May be too late to treat
What is the effect of B12 deficency on the nervous system?
Myelopathy L’hermitte’s Peripheral neuropathy Brain Eye/optic nerves Brainstem cerebellum
What are teh causes of transverse myelitis?
Viral Other infections Syphilis, measles, Lyme Autoimmune Malignancies Post vaccination (chicken pox, rabies)
What is demyelinating myelitis?
Characterised by pathological lesions of inflammation and demyelination leading to temporary neuronal dysfunction
Affects the white matter of the CNS
One or more lesions anywhere
How do you treat demyelinating myelitis?
Supportive
Methylpredinsolone
What are the clinical features of ischaemia in spinal cord?
May have vascular risk factors
Onset may be sudden or over several hours
Pain
>Back pain/radicular
Weakness
>Usually paraparesis rather than quadraparesis given vulnerability of thoracic cord to flow related ischaemia
Numbness and paraesthesia
Urinary symptoms
>Retention followed by bladder and bowel incontinence as spinal shock settles
How do you treat ischaemia in spinal cord?
Supportive Reduce risk of recurrence >Maintain adequate BP >Bed rest >Reverse hypovolaemia/arrhythmia OT and physiotherapy Manage vascular risk factors
What can cause myelopathy?
Demyelination Ischaemia Transverse myelitis Metabolic/B12 deficnecy Malignancy Lyme/AIDS Inflammation
Where does infaction of the spinal cord normally happen?
Normally affects only posterior or anterior side due to blood vessel supply
Radicular arteries off aorta/intercostal muscles
>Thoracic + bottom of s[inal cord poor blood supply
>Rare in posterior (dorsal columns spared) - usually anterior spinal artery
Usually mid thoracic
What is demyelination?
Auto immune process caused by activated T cells across blood brain barrier
Acute inflammation of myelin sheath
Leads to loss of function
>Repair-recovery of function
Post inflammatory gliosis may have functional deficit
>Lesions/plaques show up on MRIs
What is the progression of demyelination?
Axonal loss shown by black holes in MRI
Axonal loss may be present from disease onset (unkown)
Later seen as cerebral atrophy
Who is likely to get demyelination?
Females 3:1
More common further away from equator
Genetic link
Younger populace
What is the initial presentation of MS?
Gradual onset over days
Stabilises in days-weeks
Gradual resolution to complete or partial
What is the clinical presentation of an MS relapse?
Optic neuritis
Sensory symptoms
Limb weakness
Brainstem Diplopia/Vertigo/Ataxia-
Spinal cord-bilateral symptoms and signs +/- bladder
What is optic/retrobulbar neuritis?
Subacute visual loss Pain on moving eye Colour vision disturbed Usually resolves over weeks Initial swelling optic disc Optic atrophy seen later Relative afferent pupillary defect
What other diseases can cause optic neuritis?
Neuromyelitis optica Sarcoidosis Ischaemic optic neuropathy Toxic/ drugs/ B12 deficiency Wegeners granulomatosis Local compression Lebers hereditary optic neuropathy \+ others
What are the symptoms of a brainstem relapse?
Cranial nerve involvement
Pons- internuclear ophthalmoplegia
E.g. Vertigo, nystagmus, ataxia
Upper motor neurone changes limbs
What are the symptoms of myelitis?
Depends if partial or transverse
Check sensory level
Weakness/UMN changes below level
Bladder+ bowel involvement
What is MS?
Episodes of demyelination diseminated in space + time
May occur within months or years within first relapse
Variable site/severity
Diagnose with clinical (posers criteria) or MRI (macdonald)
For every 10 lesions on MRI (roughly) patient suffers 1 relapse
Scan+ symptoms may not correlate
What is the progressive phase of MS?
Accumulation of symptoms and signs >Fatigue, temperature sensitivity >Sensory >Stiffness or spasms >Balance, slurred speech >Swallowing >Bladder & bowel >Diplopia/ oscillopsia/ visual loss >Cognitive-dementia/ emotional lability
What are the signs of MS on examination?
Depends on where demyelination has occurred and stage of disease: >Afferent pupillary defect >Nystagmus or abnormal eye movements >Cerebellar signs >Sensory signs >Weakness >Spasticity >Hyperreflexia >Plantars extensor
How do you investigate MS?
MRI
Rest depend on clinical picture……
>Lumbar puncture-oligoclonal bands present in CSF but not serum
>Visual/ somatosensory evoked response
>Bloods-exclude other inflammatory conditions
>Chest X Ray
What are the differentials to MS?
Depends on symptoms and signs and on whether a first relapse or progressive disease Includes: >Acute Disseminated Encephalomyelitis >Other Auto-immune conditions eg SLE >Sarcoidosis >Vasculitis >Infection eg Lyme disease, HTLV-1 >Adrenoleucodystrophy etc etc
What are the types of MS?
Relapsing remitting-85% at outset (RRMS) Secondary progressive (SPMS) Primary progressive – 10-15% (PPMS) Sensory – 5% Malignant Describe the disease 1/4 will need a wheelchair at some point
What is the prognosis for relapse remitting MS?
Difficult to predict, however: Good for >Female >Present with optic neuritis >Long interval between 1st + 2nd relapse >Few relapses in first 5 yrs Bad for >Male >Older age >Multifocal symptoms + signs >Motor symptoms + signs
What is primary progressive MS?
Often presents in 5th and 6th decade No relapses Spinal symptoms Bladder symptoms Prognosis poor M:F = 1:1
What is devic’s disease?
Optic neuritis Myelitis Aquaporin-4 antibodies Antibody negative in some cases Treat with immuno suppression
How do you treat MS?
Beta-interferons/ glatiramer acetate Daily-weekly im/ sc injection Teriflunomide Dimethyl Fumarate >Reduce relapse rate ~1/3 >No effect on progression of disability >Not a cure
What are the side effects of first line MS treatments?
Flu-like symptoms
Injection site reaction
Abnormalities of blood count and liver function
How should you approach an acute MS relapse?
Look for underlying infections
Rehab + symptomatic treatment
Steroids - if not infection
How should you treat further MS relapses?
Vaccination to prevent
Fewer during pregnancy, increased risk in first 3 months after birth
What are the types of brain injury?
Direct trauma
Indirect trauma
What are the symptoms of brain injury?
Headache Nauzea Vomiting Dizziness Hemiparesis Seizure Double vision Cranial nerve/s palsy Ataxia Slurred speech Dysarthria Unresponsiveness Unconciousness Irregular breathing Unequal pupils Respiratory / Cardiac arrest
What are indicatiors of a direct trauma?
Bruises
Skull fracture
Closed/open injuries
Extradural haemorrhage
What are the indicators of an indirect trauma?
No bruises Subdural haematoma Traumatic SAH Contusion Diffuse aconal injury
What are teh examples of close trauma?
Haemrrhage (extra/sub dural)
Traumatic SAH
Contusion
How do you treat a brain injury?
Surgical - skull cap removal to relieve pressure
Conservative
cSF diversion
What is pain?
Unpleasant sensory + emotional experience primarily associated with tissue damage
What is the pathway of pain?
Periphery >Detection + transmission to spinal cord Spinal cord >Processing + transmission t brain (thalamus) Brain >Perception, learning, response Modulation >Descending tracts
What diseases change perception of pain?
Allodynia
Hyperalgesia
Spontaneous pain
What is spontaneous pain?
Spontaneous activity in nerve fibres
What is Allodynia?
Decreased threshold for response
What is Hyperalgesia?
Exaggerated response to normal stimuli
What is central centralisation?
Response of second order neurone in CNS to both noxious + non noxious stimuli
Wind up, classical + long term potentiation components
What is wind up?
Involves only activated synapses
Homosynaptic activity dependent progressive increase in response of the neurons
Manifests over the course of stimuli & terminates with stimuli
only in neurons taking part in the synapses with primary afferent input.
It is activity dependent; progressively increases the response of the neurons.
terminates with stimulus.
What is central sensation?
Involves opening up of new synapses (silent nociceptors)
Heterosynaptic activity dependent plasticity
Immediate onset with appropriate stimuli
Outlast the initial stimuli duration
Can be maintained even at low levels of ongoing stimuli
What is long term potentiation?
Involves mainly the activated synapses
Occurs primarily for
very intense stimuli
What is nocioceptive pain?
Painful region is typically localised at the site of injury – often described as throbbing, aching or stiffness
Usually time limited and resolves when damaged tissue heals (e.g. bone fractures, burns and bruises)
Can also be chronic (e.g. osteoarthritis)
Tends to respond to conventional analgesics
What is neuropathic pain?
Pain initiated or caused by a primary lesion or dysfunction in the somato-sensory nervous system
The painful region may not necessarily be the same as the site of injury – pain occurs in the neurological territory of the affected structure (nerve, root, spinal cord, brain)
Almost always a chronic condition (e.g. postherpetic neuralgia [PHN], poststroke pain)
Responds poorly to conventional analgesics
What are the differences between acute and chronic pain?
Acute pain is physiological, whereas chronic is pathological
Noxious stimuli not needed in chronic, but is in acute
Chronic does not serve a purpose
Acute pain is usually nociceptive pain, chronic can be any
What can help the transduction part of the pain pathway?
NSAIDs
Ice
Rest
LA blocks
What can help the transmission part of the pain pathway?
Nerve blocks Drugs >Opioids >Anticonvulsants Surgery
What can help the perception part of the pain pathway?
Education Cognitive behavioural therapy Distraction Relaxation Graded motor imagery Mirror box therapy
What can help the descending modulation part of the pain pathway?
Placebos Drugs >Opioids >Antidepressants Surgery >Spinal cord stimulation
