vertigo (see DM) Flashcards
(39 cards)
what modulates normal balance
continuous interaction between vestibular, proprioceptive and visual mechanisms which are all modulated by the CNS
what is vertigo
a sensation of dizziness or abnormal motion resulting from a disorder of the sense of balance
how do environmental factors affect balance control (sensory pathway)
environmental interaction -> visual, vestibular and somatosensation systems provide info about the body position -> compare, select and combine sense -> determination of body position
if there is a lesion in the Thalamo-Cortical Structure what is the presentation (vestibular)
conscious illusion of spinning
if there is a lesion in the occulomotar nuclei what is the presentation (vestibular)
nustagmus
if there is a lesion in the spinal chord what is the presentation (vestibular)
lateropulsion (tendancy to veer to one side)
if there is a lesion in the cerebellum what is the presentation (vestibular)
gait ataxia
if there is a lesion in the autonomic medullary centres what is the presentation (vestibular)
autonomic symtpoms e.g. sweating, vomiting
what is vestibular compensation
a process that allows the brain to regain balance control and minimise dizziness symptoms when there is damage to one of the vestibular organs - due to ON/OFF tonic signaling from the vestibular organs
what changes are seen in the brains of ballet dancers (vestibular)
through spotting, the brain has adapted to suppress activity in the cerebrum and cerebellum associated with vestibular function
examples of general medical causes of vertigo (6)
- Anaemia
- postural Hypotension
- Carotid Sinus Syndrome
- Dysrhythmia
- Hypoglycaemia
- Hyperventillation
examples of neurological causes of vertigo (8)
- Epilepsy
- Migraine
- Syncope
- Psychogenic
- Multiple Sclerosis
- Cerebral Ischaemia
- Infective disorders
- Tumours
otological causes of vertigo (10)
- Menière’s Disease
- Post Traumatic Syndrome
- Positional Nystagmus
- Vestibular Neuronitis
- Infection
- Otosclerosis and Paget’s Disease
- Vascular accidents
- Tumours
- Auto-immune disorders
- Drug intoxication
what are the 3 most common peripheral vestibular causes of vertigo
- Benign Paroxysmal Positional Vertigo (BPPV)
- Menière’s disease (or syndrome)
- Vestibular Neuronitis
how does alcohol cause vertigo
the endolymph becomes less viscous with the consumption of alcohol, this allows the hair cells to move more easily within the ear, which sends the signal to the brain and results in exaggerated and overcompensated movements of body
what is “true vertigo” a disease of
the semicircular canals and their CNS connections - has accompanying symptoms of gait unsteadiness, nausea, vomiting etc.
what is the commonest cause for single attack of vertigo
vestibular neuronitis
what is the commonest cause for recurrent spontaneous vertigo
migraine
what is the commonest cause for positional vertigo
BPPV
what does a vertigo attack that lasts seconds indicate the cause could be
vestibular paroxsysms, cardiac arrythmias, BPPV
what does a vertigo attack that lasts hours indicate the cause could be
meniere’s disease, migraine
what does a vertigo attack that lasts days indicate the cause could be
vestibular neuronitis, brainstem/cerebellar stroke
how to distinguish BPPV from other positional causes e.g. orthostatic hypotension
BPPV arises from a specific reorientation of the head e.g. rolling over in bed or turning the head, rather than a change in head position e.g. sitting to standing
what does vertigo + red eyes, skin rashes arthritis etc. indicate
autoimmune inner-ear disease
