Neurology Flashcards
example and action of 5-HT3 antagonists
e.g., ondansetron
antiemetics - used in management of chemo-therapy-related nausea
act in chemoreceptor trigger zone of medulla oblongata
S/E - QT prolongation, constipation
features of wernicke’s aphasia
receptive aphasia
sentences make no sense, word substitution, neologisms, fluent speech - word salad
impaired comprehension
lesion in wernicke’s aphasia
due to lesion of superior temporal gyrus
supplied by inferior division of left MCA
lesion in broca’s aphasia
lesion of the inferior frontal gyrus
supplied by the superior division of the left MCA
features of broca’s aphasia
non-fluent, laboured, and halting speech
impaired repitition
normal comprehension
features of conduction aphasia
speech fluent, repetition poor
aware of errors
normal comprehension
lesion in conduction aphasia
due to a stroke affecting the arcuate fasiculus - the connection between Wernicke’s and Broca’s area
features of global aphasia
non fluent, comprehension impaired, severe expressive and receptive aphasia
definition of arnold chiari malformation
herniation of the cerebellar tonsils through the foramen magnum
may be congenital or acquired (traumatic)
features of arnold chiari malformation
non-communicating hydrocephalus may develop as a result of obstruction of cerebrospinal fluid (CSF) outflow
headache
syringomyelia
causes of ataxia
Cerebellar hemisphere lesions cause peripheral (‘finger-nose ataxia’)
Cerebellar vermis lesions cause gait ataxia
features of ataxia telangiectasia
an autosomal recessive disorder caused by defective ATM gene (encodes for DNA repair enzymes - combined immunodeficiency disorders
cerebellar ataxia - inability to coordinate muscle movement
telangiectasia
IgA deficiency
describe autonomic dysreflexia
clinical syndrome in those with SC injury above T6
afferent signals (due to faecal impaction/urinary retention) cause sympathetic spinal reflex via thoracolumbar outflow
parasympathetic response is prevented due to lesion
therefore unbalanced physiological response leads to - extreme hypertension, flushing and sweating above the level of the cord lesion, agitation
definition of bells palsy
acute, unilateral, idiopathic, facial nerve paralysis
features of bells palsy
LMN - forehead affected
UMN - forehead sparing
post-auricular pain (may precede paralysis)
altered taste
dry eyes
hyperacusis
management of bells palsy
oral prednisolone <72 hours of onset
eye care - prevent exposure keratopathy
if paralysis not improved after 3 weeks - urgent ENT referral
refer to plastic surgery if long standing weakness
normally full recovery <3-4m
branchial plexus nerve roots
C5 to T1
erb duchenne paralysis
damage to C5,6 roots
winged scapula
may be caused by a breech presentation
klumpke’s paralysis
damage to T1
loss of intrinsic hand muscles
due to traction
presentation of brain abscess
depends upon the site of the abscess
considerable mass effect, raised ICP
dull persistent headache
fever
focal neurology (due to raised ICP) - and nausea, papilloedema, seizures
management of brain abscess
surgery - craniotomy, abscess cavity debrided
IV ceftriaxone + metronidazole
ICP mx dexamethasone
features of parietal lobe lesions
sensory inattention
apraxias
astereognosis (tactile agnosia)
inferior homonymous quadrantanopia
Gerstmann’s syndrome (lesion of dominant parietal): alexia, acalculia, finger agnosia and right-left disorientation
features of occipital lobe lesions
homonymous hemianopia (with macula sparing)
cortical blindness
visual agnosia
features of temporal lobe lesions
Wernicke’s aphasia: this area ‘forms’ the speech before ‘sending it’ to Brocas area. Lesions result in word substituion, neologisms but speech remains fluent
superior homonymous quadrantanopia
auditory agnosia
prosopagnosia (difficulty recognising faces)