Neurological disorders Flashcards
What are the origins of syncope (fainting)? Why does it occur?
Vaso-vagal origin usually, can be carotid sinus
Occurs due to overactivity of sympathetic nervous system (initially tachycardic, when fainting theres a reflex bradycardia)
What questions should you ask someone who presents with epilepsy in their MH?
- Precipitating factors/ any warning?
- Does the medication work in controlling seizures?
- When was the last seizure?
- Any change in medication
What is a Grand Mal seizure/ Generalised motor seizure?
Classically preceded by an aura, LOC follows leading to convulsions. Tonic phase where muscles contracted giving way to clonic phase where theres repetitive jerky movements, increased salivation and marked bruxism. Altered breathing, cyanosis and tongue biting. Affects both sides of brain.
What is Status Epilepticus?
Grand Mal seizure that has continued for 5+ mins/ doesnt have a proper end. Medical emergency as pt can become hypoxic
What is Absence Seizure/ Petit Mal/ Generalised non-motor seizure?
Seen in children- speech/attention affected (not to be confused with febrile convulsion in pyrexic child). Pt stops what they are doing and stares, may do repetitive movements. Affects both sides of brain.
What is a Stokes-Adams Attack?
Result of cardiac arrythmias, often no warning or palpitations, drop attacks - LOC
What is a partial seizure/focal epilepsy?
Can be simple = clonic movements of a group of muscles/limbs or complex = involving hallucinations. Develops in one side of brain. 4 types: 1) Focal aware 2) Focal impaired (confusion) 3) Focal motor (spasm) 4) Focal non-motor (changes in thought)
What is a TIA? What medication is a patient put on?
- Sudden onset of focal CNS signs due to temporary occlusion of part of cerebral circulation (usually secondary to atheromatous deposits in carotid artery)
- Resolves less 24 hrs
- Indicators of stroke risk
- Usually put of 75mg aspirin
What is multiple sclerosis?
Demyelination of the myelin sheath resulting in short circuits. Can have sensory and motor symptoms e.g. optic neuritis causing visual disturbances, weakness or paralysis of limbs, nystamus (involuntary rapid movement eyeballs), ataxia (uncoordinated involuntary movement), loss of sphincter control causing difficulting swallowing or incontinence. Viral aetiology postulated.
What treatment is given for multiple sclerosis which can help long term prognosis?
Steroids
What is Parkinsons Disease?
Degeneration of the pigmented cells of the substania nigra leading to dopamine deficiency. May result form previous head injury or cerebrovascualr disease. Presence of Lewy bodies (abnormal protein aggregates in nerve cells) and neurites. Affects 1% >60year olds
What are the signs and symptoms of Parkinsons disease?
- Pill rolling tremor
- Cog wheel rigidity on movement ie stop/start
- Bradykinesia ie slow movement
- Akathisia ie restless movement
- Expressionless face
- Stooped posture
- Shuffling gait
- Impaired autonomic function leading to postural drop in BP
What difficulties can occur for a patient with motor neurone disease?
- Dysphagia - difficulty swallowing so can develop aspiration pneumonias
- Respiratory difficulties - given tracheostomy
- Suffer from ascending infection e.g. UTI
What is myasthenia gravis?
Antibody mediated autoimmune disease with a deficiency of functioning Ach receptors. Commonly affects young women and presents with muscles getting tired when they are working
Are brain tumours more common as primary or metastases?
Metastases - from lung, breast, GIT and kidney
What is Eaton-Lambert syndrome?
Seen in patients with lung/other cancers where muscles get stronger rather than weaker with activity
What is bulbar palsy? What cranial nerves does it affect?
- Palsy of tongue, MoM, swallowing and facial muscles due to loss of function of motor nuclei in brainstem
- Caused by infection e.g. polio, guillain Barre (acute) or tumour (chronic)
- Affects IX, X, XI, XII
What long term drug use can cause tics/ involuntary facial movements?
Phenothiazine
What is Ramsay-Hunt Syndrome (EXAM Q)?
Profound facial paralysis with vesicles in the pharynx and external auditory meatus of the same side. Geniculate ganglion of VII is infected with herpes zoster.
How can bacterial meningitis occur in maxillofacial injuries? What is worse, bacterial or viral?
Injuries involving the mid third of face (cribiform plate and cranial base) can get ascending infection into the meningeal layers of the brain (Dura =outer, arachnoid, pai mater =inner)
Viral milder and self-limiting
What are the signs of meningitis?
- Kernig’s sign - legs flexed 90 degrees at hips and resistence to extending knee
- Severe headache
- Nausea/vomiting
- Painful still neck
- Photophobia
- Purpuric rash (doesn’t fade on pressure)
How can brain abscesses occur?
- Secondary to infection e.g. oral sepsis, infection of middle ear, paranasal sinus infection
- From septic emboli in patients with congenital heart disease
- Complication of infective endocarditis
What are the 3 main types of cerebral palsy?
1) Spastic = muscles contracted
2) Ataxic = disturbance of balance
3) Athetoid = writhing movements
What is cerebral palsy?
Disorder of motor function secondary to cerebral damage - frequently associated with birth injury or hypoxia
What is spina bifida?
Vertebral arches fail to fuse - thought to be due to folic acid deficiency. Causes inability to walk, epilepsy or learning difficulties. May be associated with hydrocephalus (retention of CSF in brain)
What are 2 distinct clinical features of spina bifida?
- Tuft of hair at base of spine
- Meningocele - where meningeal layer surrounding spinal cord herniates out between the bones of vertebrae (usually lumbar)
What is Huntington’s Chorea?
Progressive dementia with marked involuntary movements. Autosomal dominant and early onset of middle age.
What is a stroke?
Sudden focal loss of neurological function due to disruption of blood supply to part of the brain - permanent damage and disabling
What are the 2 main pathophysiologies/causes of a stroke?
Ischaemic, infarction, occlusive stroke (90%)
- Atherosclerosis (artery fatty deposit)
- Thrombosis (blood clot forms on plaque)
- Embolism (solid material from somewhere else e.g. travelling blood clot)
Haemorrhage (10%)
How can you tell if there has been a cerebral haemorrhage from a CT scan?
White - RBC have iron which absorb x rays
How can you tell if there has been an ischaemic stroke from a CT scan a)mild b) severe?
a) Subtle changes e.g. sulci on brain less visible
b) Dark from infarction
What are the risk factors of a stroke?
- Age
- Smoking
- Diabetes
- Hypertension
- Coagulation disorders
- Atrial fibrillation
- Hyperlipidaemia
What measures can be taken to prevent strokes?
- Treat risk factors (Primary prevention)
- Medications (Secondary prevention): antiplatelet (aspirin or clopidogrel), anticoagulants (warfarin or newer NOACs e.g. dabigatran, apixaban)
- Surgery if carotid arteries narrow: surgical endarterectomy for stroke due to carotid stenosis
Clinical stroke syndromes depend on site and severity of damage. What do the following stand for?
a) TACS
b) PACS
c) LACS
d) POCS
a) Total anterior circulation stroke
b) Partial anterior circulation stroke
c) Lacuna stroke
d) Posterior circulation stroke
What test is used in hospitals to recognise stroke? What test do members of the public use?
ROSIER scale: 1 point for asymmetrical arm, leg or face weakness, speech disturbance or visual field defect. -1 point for LOC or seizure
1-6=likely stroke. -2-0= stroke unlikely
FAST
Once a patient is in hospital, what is the acute stroke management?
Thromolysis within 4.5 hrs to dissolve blood clots
CT head, ECG, CXR, FBC, lipids, clotting, U+E, glucose
Careful monitoring
Aspirin once haemorrhage excluded - clopidogrel for long term
What is a transient ischaemic attack (TIA)?
Transient focal neurological deficit lasting less than 24 hours, usually less than an hour
What do the following mean?
a) Dysarthria
b) Dysphonia
c) Dysphasia - expressive and receptive
a) speech slurred
b) can’t produce voice
c) higher cerebral function not working: expressive = Broca’s - can’t find the word. Receptive = Wernicke’s - can’t understand what is said
What are the 3 phases of swallowing and which phases does a stroke affect?
1) Oral = mastication, bolus, back of mouth
2) Pharyngeal = semi-voluntary, propelled back, epiglottis closes to protect airway
3) Oesophageal = involuntary and automatic
Affects 1 and 2 more
What are some causes of dysphagia?
- Stroke - danger of aspiration pneumonia as no cough reflex
- Neurological disease e.g. motor neurone
- Oesphageal motility disorders
- Mechanical obstruction e.g. oesophageal cancer, benign stricture from reflux scarring, extrinsic compression from lung cancer
What assessments would be done if you suspect problems swallowing are due to:
a) Oropharyngeal reasons
b) Oesophageal dysmobility
c) Oesophageal obstruction
d) Suspected cancer
a) SALT and videofluoroscopy (swallowing Xray)
b) Barium swallow
c) Barium swallow or endoscopy
d) Endoscopic biopsy, CT scan
What is offered in the following treatments
a) Neurological
b) Mechanical
c) Diet modification
d) Tube feeding
a) SALT
b) Dilation, stent, surgery
c) Puree
d) nasogastric, PEG feeding (percutaneous endoscopic gastrocopy endoscope through abdominal wall into stomach)
What compensatory mechanisms are part of intracranial pressure autoregulation?
- Decreasing the production of CSF
- Restricting blood flow to brain by vasoconstriction
What are the indications of a head injury?
- Scalp wound
- Fracture
- Dizziness, blurred vision
- Swelling, bruising
- Loss of consciousness
- Stiff neck, numbness
- Watery clear discharge out of nose/ears indicated cranial base injury
- Headache
- Nausea vomiting
- Difficulty remembering incident
- Sensitivity to light
What should you do if there has been a scalp injury?
- Bleeds profusely so apply direct pressure
What are skull injuries divided into?
- Open skull fractures (compound fracture)
- Closed skull fracture
- Basal skull fracture
What is a primary (direct) brain injury?
Occurs at time of original insult, direct damage to prain parenchyma and associated with vascular injuries
What is a primary (direct) brain injury?
Occurs at time of original insult, direct damage to brain parenchyma and associated with vascular injuries. Brain tissue can be lacerated, punctured or bruised. Damage irreversible - can debride.
What is a secondary brain injury?
Damage after initial insult. Expanding mass lesions, swelling, bleeding quickly. Increased intracranial pressure or brain herniation
What is a concussion?
Transient alteration in neurological function. Mild injury from blunt trauma with no detectable brain damage but short term memory loss
What is a contusion?
A bruised brain from closed head injuries where the brain has hit the inside of the skull. Unconsciousness can occur. Remember contrecoup effect (other side of brain)
What is a diffuse axonal injury?
Rotational forces on the brain causing snapping and stretching of axons. Disturbance can produce temporary or widespread damage, coma or death.
What is a sub-dural haemotoma?
Blood between dura mater and arachnoid - slow bleeding as venous from cortical bridging veins.
Can cross sutures, crescent shaped on CT.
Loss of consciousness and common in elderly due to cerebral atrophy and anticoagulants.
What is an extra-dural haematoma?
Blood between dura and skull base - quick as artery (middle meningeal artery). Skull fractures in temporo-parietal region
Cannot cross sutures, lens shaped on CT, lucid interval
What is an intracerebral haematoma?
Blood within the brain parenchyma
What are the symptoms of an early intracranial haemorrhage?
- Nausea
- Severe head pains
- Dizziness
- Sleepiness
- Unequal pupil size
What are the symptoms of late intracranial haemorrhage?
- Convulsions
- Deteriorating consciousness
- Increased BP
- Slow pulse
- Slow respiration
- Neck rigidity
What imaging techniques are used in a brain injury?
X-rays - show bone only
CT and MRI - show more anatomy and density of blood
What are the layers of the brain outer to inner?
Skull - dura mater - arachnoid mater - subarachnoid space - pia mater - brain
What is the management of a patient presenting with a head injury?
1) ABCDE - intubate comatose pt <8GCS and immobilise spine
2) Neurological evaluation - ACVPU, GCS, treat intracranial pressure (IPC bolt to monitor <8GCS pt), manage seizures
3) Radiological evaluation
4) Treat acute injuries - direct = oxygenation and perfusion and ICP, intracranial haematomas = if subdural then craniotomy for evacuation, if intra-parnchymal then no surgery, treat ICP medically (osmotic diuretic mannitole)
What is GCS?
Eye opening response up to 4 points, verbal response up to 5 points, motor response up to 6 points.
3=comatosed, 15= fully alert
What is a subarachnoid haemorrhage? What causes this?
Bleeding beneath the arachnoid membrane
Burst cerebral aneurysms
What does ACVPU stand for?
- Alert
- New onset confusion
- Responds to voice
- Responds to pain
- Unresponsive
Define these words: a) Catelepsy b) Ambivalence c) Psychosis d) Dementia e) Neurosis
a) Trancelike state with holding of 1 pose for a long time
b) Feeling of conflicting emotions about the same person/issue
c) Extreme disordered thinking - pt doesn’t know they have it
d) Disorder of multiple cognitive defects (mainly in elderly)
e) Pt knows they have disordered thinking
a) What is alzheimers disease?
b) Who does it effect?
c) What causes it?
d) What are the symptoms?
e) What are the implications for dental treatment?
a) A form of dementia (not all dementia pts have this)
b) 20% people over 80 years
c) Genetic and ?environmental factors. ?cerebral atrophy in old age
d) Reduced social function, intellect, speech, memory and concentration, onset insidious and pt unaware of impairment
What are the complications of alcoholism?
- Injuries
- Nutritional defects
- Brain damage, epilepsy and myopathy
- Cardiomyopathies
- Gastritis
- Pancreatitis
- Liver damage
- Social problems
What is Korsakoff’s Psychosis?
Amnesia of recent events, impaired ability to learn new tasks, fabricated descriptions of recent events (confabulation) otherwise alert and normal - due to chronic alcoholism causing thiamine deficiency (B vit)
What are the medical complications of bulimia?
- Dehydration/weight fluctuations
- Low potassium causing muscle cramps
- Dental erosion
- Acidosis/alkylosis
- Oesophagitis
- Poor muscular tone in colon from laxative abuse