Neuro Flashcards
Parietal Lobe Lesions - disorders
sensory inattention
apraxias
astereognosis (tactile agnosia)
inferior homonymous quadrantanopia
Gerstmann’s syndrome (lesion of dominant parietal): alexia, acalculia, finger agnosia and right-left disorientation
Occipital Lobe Lesions
homonymous hemianopia (with macula sparing)
cortical blindness
visual agnosia
Temporal Lobe Lesion - disorders
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)
Frontal Lobe Lesions - disorders
expressive (Broca’s) aphasia: located on the posterior aspect of the frontal lobe, in the inferior frontal gyrus. Speech is non-fluent, laboured, and halting
disinhibition
perseveration
anosmia
inability to generate a list
Cerebellum Lesions - Disorders
midline lesions: gait and truncal ataxia
hemisphere lesions: intention tremor, past pointing, dysdiadokinesis, nystagmus
Lesions at Medial thalamus and mammillary bodies of the hypothalamus
Wernicke and Korsakoff syndrome
Subthalamic nucleus of the basal ganglia - lesion - disorder
Hemiballism
Striatum (caudate nucleus) of the basal ganglia
Huntington Chorea
Substantia nigra of the basal ganglia - lesion - disorder
Parkinsons
Amygdala - lesion - disorder
Kluver-Bucy syndrome (hypersexuality, hyperorality, hyperphagia, visual agnosia
What does the facial nerve supply?
face: muscles of facial expression
ear: nerve to stapedius
taste: supplies anterior two-thirds of tongue
tear: parasympathetic fibres to lacrimal glands, also salivary glands
Causes of bilateral facial nerve palsy
sarcoidosis
Guillain-Barre syndrome
Lyme disease
bilateral acoustic neuromas (as in neurofibromatosis type 2)
as Bell’s palsy is relatively common it accounts for up to 25% of cases f bilateral palsy, but this represents only 1% of total Bell’s palsy cases
Causes of unilateral facial nerve palsy
Same as bilateral PLUS
Stroke
Bell’s palsy
Ramsay-Hunt syndrome (due to herpes zoster)
acoustic neuroma
parotid tumours
HIV
multiple sclerosis*
diabetes mellitus
Facial nerve palsy - upper vs lower motor neurone lesion
Forehead sparing in upper motor neurone not in lower
Most common psychiatric symptoms of Parkinson’s
psychiatric features: depression is the most common feature (affects about 40%); dementia, psychosis and sleep disturbances may also occur
What is Brown-Sequard syndrome
caused by lateral hemisection of the spinal cord
ipsilateral weakness below lesion
ipsilateral loss of proprioception and vibration sensation
contralateral loss of pain and temperature sensation
Features of HSV encephalitis
fever, headache, psychiatric symptoms, seizures, vomiting
focal features e.g. aphasia
peripheral lesions (e.g. cold sores) have no relation to the presence of HSV encephalitis
Investigations for HSV encephalitis
CSF: lymphocytosis, elevated protein
PCR for HSV
CT: medial temporal and inferior frontal changes (e.g. petechial haemorrhages) - normal in one-third of patients
MRI is better
EEG pattern: lateralised periodic discharges at 2 Hz
Treatment for HSV encephalitis
IV aciclovir
General features of myotonic dystrophy
myotonic facies (long, ‘haggard’ appearance)
frontal balding
bilateral ptosis
cataracts
dysarthria
Four D’s of myotonic dystrophy
Distal weakness initially
autosomal Dominant
Diabetes
Dysarthria
What is syringiomelia?
Syringomyelia (‘syrinx’ for short) describes a collection of cerebrospinal fluid within the spinal cord.
What causes syringomelia?
a Chiari malformation: strong association
trauma
tumours
idiopathic
Features of syringomelia
a ‘cape-like’ (neck, shoulders and arms)
loss of sensation to temperature not light touch, proprioception, vibration
classic examples are of patients who accidentally burn their hands without realising
spastic weakness - LL mainly
neuropathic pain
upgoing plantars
autonomic features:
Horner’s syndrome due to compression of the sympathetic chain, but this is rare
bowel and bladder dysfunction
scoliosis - over years
Types of multiple system atrophy
MSA-P — mainly Parkinson features
MSA-C — mainly cerebellar features
Features of multiple system atrophy
Parkinsonism
Autonomic disturbance - erectile dysfunction, postural hypotension, atonic bladder
Cerebellar signs
Classify focal seizures
Start in specific part of brain
Level of awareness varies
Motor, non motor or aura
Classify generalised seizures
Both sides of brain
Immediately LoC
Motor or non motor
Types - tonic clonic, tonic, clonic, typical absence, atonic
Describe infantile spasms
Brief spasms in first months of life
Flexion of head, trunk and limbs
Progressive mental handicap
EEG - hypsarrhythmia
Secondary to serious neuro abnormality
Vigabatrin or steroids
Poor prognosis
Describe absence seizures
Age 4-8
Few seconds, no warning, quick recovery, many per day
EEG - 3Hz generalised, symmetrical
Valproate
Good prognosis
Lennox-Gestault syndrome
Extension of infantile spasms sometimes
Age 1-5yr
Atypical absences, falls, jerks
90% moderate-severe handicap
EEG - slow spike
Ketogenic diet may help
Benign Rolandic epilepsy features
Most common in childhood and males
Paraesthesia usually on waking up
Juvenile myoclonic epilepsy features
Typically teenager
Infrequent generalised seizures often in morning - sleepy
Daytime absences
Sudden shock like myoclonic seizure
Good response to valproate
Treatment for generalised tonic-clonic seizures
Males - valproate
Females - lamotrigine or keppra
Treatment for focal seizures
Lamotrigine or keppra first
Carbamazepine, oxcarbazepine, zonisamide
Absence seizures treatment
Ethosuximide
Valproate for men
Lamotrigine or keppra for women
Not carbamazepine
Treatment for myoclonic seizures
Valproate for men
Keppra for women
Tonic or atonic seizure treatment
Valproate for men
Lamotrigine for women
Anti epileptic drugs and pregnancy issues
Valproate - neural tube defects
Phenytoin - cleft palate - give Vit K in last month of pregnancy
First step of managing status epilepticus out of hospital
10-20mg diazepam PR
Status epilepticus treatment
Early - lorazepam
Established - phenytoin infusion or posphenytoin infusion, phenobarbital infusion
Refractory - propofol, midazolam, thiopental sodium