neuro7 Flashcards
(27 cards)
vertigo
illusion r hallucination of movement that is usually rotatory but can be linear
dysequilibrium
feeling of imbalance or unsteadiness that is usually referable to the legs rather than to a feeling inside the head
cause of vertigo
caused by an acute asymm or imbalance of neural activity between the left and right vestibular systems; NOT from symmetric bilat loss of vestibular function or from slow unilat loss
vertigo with tinnitus and hearing loss
peripheral cause
vertigo with diplopia, dysarthria, dysphagia, or other brainstem sx
central process
vestibular neuronitis
acute unilateral peripheral vestibulopathy; not actually inflamm; acite onset of vertigo, nausea, and vomiting; nystagmus is unilateral and may be supp by fixation
labrynthe concussion
may result from head injury ; vertigo sometimes accompanied by hearing loss and tinitus
infarction of the labrynthe, brainstem, or cerebellum
can cause vertigo
blood supply to the ventral and peripheral vestibular apparatus and the cerebellum
vertebrebasilar system (post and ant inferior cerebellar arteries and the superior cerebellar artery)
blood supply to the inner ear
internal auditory artery, a branch of the anteroinferior cerebellar artery
infarction of the inner ear presents how?
sudden onset of deafness, vertigo, or both
number one cause of suspected acute vestibular neuronitis
brainstem or cerebellar stroke; causses central-type nystagmus
Meniere disease
intermittent incr in endolymphatic volume;episodic vertgo with n/v; fluctuating but progressive hearing loss; tinnitus; and a sensation of fullness or pressure in the ear
perilymph fistula
results from disruption of the lining of the endolymphatic system
patient hears a sudden pop and then onset of vertigo
perilymph fistula
benign positional paroxysmal vertigo
episodes of vertigo are precipitated by changes in position; results from freely moving crystals of calcium carbonate in one of the semicirc canals that keep activating the nerve
diagnosis of BPVV
Dix-Hallpike test; the offending ear is toward the ground when vertigo occurs;
how to remove the crystals from the posterior circ canal in BPVV
a positioning (Epley) maneuver
syncope
transient loss of consciousness and postural tone that results from brain hypoperfusion
presyncope
patients experience the prodrome of syncope without losing consciousness
neurogenic syncope
sudden change in activity of the ANS ; excessive afferent discharge from arterial or visceral mechanoreceptors via the vagus nerve leads to cardioinhib and vasodepression, resulting in hypotension nad bradycardia
micturition syncope
triggered by rapid emptying of a distended bladder
carotid sinus hypersensitivity
compression of the carotid sinus leads to syncope
neurocardiogenic syncope
vigorous contraction of an underfilled ventricle is the trigger