Neurology Flashcards
(264 cards)
Define aphasia and list the 4 types
A disorder where a person has difficulty with their language and speech - the 4 types are:
1) Wernicke’s (receptive)
2) Broca’s (expressive)
3) Conduction
4) Global
What is Wernicke’s aphasia?
Due to a lesion of the superior temporal gyrus (supplied by the inferior division of the left MCA) - speech remains fluent but nonsensical - comprehension is impaired
What is Broca’s aphasia?
Due to a lesion of the inferior frontal gyrus (supplied by the superior division of the left MCA) - speech is non-fluent, laboured and halting w/ impaired repetition - comprehension is normal
What is Conduction aphasia?
Classically due to a stroke affecting the arcuate fasciculus (conneection between Wernicke’s and Broca’s areas) - speech is fluent but repetition is poor, aware that they are making mistakes - comprehension is normal
What is Global aphasia?
Large lesion affecting the superior temporal gyrus, inferior frontal gyrus and arcuate fasciculus - severe expressive and receptive aphasia
Define an Arnold-Chiari malformation
This is the downwards herniation of the cerebellar tonsils through the foramen magnum - may be congenital or acquired through trauma
Arnold-Chiari malformation features
Non-communicating hydrocephalus (CSF outflow obstruction), headache, syringomyelia
Define ataxia
Poor muscle control resulting in uncoordinated movements
Define Ataxia telangiectasia
An autosomal recessive primary immunodeficiency
Ataxia telangiectasia features
Cerebellar ataxia, telangiectasia, IgA deficiency, typically presents in early childhood w/ abnormal movements
Define Autonomic dysreflexia
A clinical syndrome which occurs in pts who have a spinal cord injury at, or above T6 spinal level. In response to a noxious stimulus below the level of the spinal cord injury (commonly faecal impaction or urinary retention), there is massive reflex sympathetic discharge. This results in vasoconstriction and hypertension. However, due to the lesion in the spinal cord, this sympathetic response cannot be regulated by the brain.
Above the level of injury, where neural connections are intact, parasympathetic activity via vagal stimulation tries to counteract this by causing vasodilation and bradycardia. However, this compensatory mechanism is only effective above the level of injury and cannot offset the hypertensive crisis occurring below it.
Autonomic dysreflexia features
Characterised by extreme hypertension, flushing and sweating above the level of the cord lesion, agitation, haemorrhagic stroke if HTN not treated
Autonomic dysreflexia management
Removal/control of the stimulus and treatment of any life-threatening HTN and/or bradycardia
Bell’s palsy features
Facial nerve palsy that DOES NOT spare the forehead, post-auricular pain, altered taste, dry eyes, hyperacusis
Bell’s palsy managment
All pts should receive oral prednisolone w/in 72 hours of symptom onset, eye care to avoid exposure keratopathy (prescribe artificial tears and eye lubricant, tape eye closed at bedtime), consider adding antivirals - if no improvement after 3 weeks then refer to ENT
Define Erb-Duchenne paralysis
Damage to the C5/6 roots in the brachial plexus (commonly by breech presentation) - causes winged scapular
Define Klumpke’s paralysis
Damage to T1 at the brachial plexus (usually due to traction) - causes a loss of intrinsic hand muscles
Brain abscess management
Surgery (craniotomy performed and the abscess cavity is debrided), IV abx (cephalosporin + metronidazole), dexamethasone to control ICP
Define Brown-Sequard syndrome
A lateral hemisection of the spinal cord
Brown-Sequard features
Ipsilateral weakness below the lesion, ipsilateral loss of proprioception and vibration sensation, contralateral loss of pain and temp (spinothalamic)
Define cataplexy
The sudden and transient loss of muscular tone caused by a strong emotion (ranging from buckling knees to collapse) - related to narcolepsy
Cerebellar syndrome features
DANISH = Dysdiadochokinesia, dysmetria, ataxia, nystagmus, intention tremor, speech disturbance, hypotonia
Causes of Cerebellar syndrome
Inherited (Freidreich’s ataxia, ataxia telangiectasia), cerebellar haemangioma, stroke, alcohol, MS, hypothyroidism, drugs (anti-epileptics, lead poisoning), paraneoplastic secondary to lung cancer
Define cerebral perfusion pressure
The net pressure gradient causing blood flow to the brain. A sharp rise in CPP may cause in a rise in ICP, a fall in CPP may result in cerebral ischaemia - calculated using:
CPP = mean arterial pressure - intracranial pressure