Vestibular System Flashcards
This is the sensory apparatus of the vestibular system
Series of interconnected canals
Labyrinth
The labyrinth of the vestibular system is encased within this structure
Temporal bone
These are the two Otolith organs
Detect linear acceleration and static gravitational forces
Utricle and Sacculus
Vestibular hair cells are innervated by this
Bipolar cells of the vestibular ganglion
Do vestibular hair cells consists or a single or multiple kinocilium?
Single
Do vestibular hair cells consists or a single or multiple stereocilia?
Multiple
Is the kinocilium at the base or apex of the vestibular hair cell?
Apex
This structure within the otolith organs form the divide between hair cells with opposing orientations
Striola
The striola forms the divide between hair cells with opposing orientations, and is found within this
Otolith organs
(utricle and sacculus)
In the otolith organs, hair cells are surrounded by this
Gelatinous matrix
This membrane is on top of the gelatinous matrix
Otolithic membrane
These are on top of the otolithic membrane, and are moved by gravity or linear acceleration
Calcium carbonate crystals
Calcium carbonate crystals are on top of this structure of the otolith organs
Otolithic membrane
The hair cells of the sacculus and utricle are located within this
Macula
The macula of the sacculus or utricle is oriented in the vertical plane?
Sacculus
The macula of the sacculus or utricle is oriented in the horizontal plane?
Utricle
These structures of the vestibular system detect angular acceleration in three different dimensions
Semicircular canals
This semicircular canal detects yaw/spinning
Horizontal
This semicircular canal detects pitch/tumbling
Anterior (aka superior)
This semicircular canal detects roll/cartwheel
Posterior
Scarpa’s ganglion is another name for this
Vestibular ganglion
Each hair cell synapses onto bipolar cells whose somi are located in this ganglion
Vestibular ganglion
(aka Scarpa’s)
Vestibular nuclei project to the motor nuclei that innervate the extraocular muscles, via this
MLF
Is the ascending MLF to Extraocular muscles vestibular pathway unilateral or bilateral?
Bilateral
(these connections mediate the VOR)
These are the two descending connections the vestibular nuclei have to the spinal cord
Descending portion of MLF
Vestibulospinal tract
Does the vestibulospinal tract project to ipsilateral or contralateral motor nuclei in the ventral horn?
Ipsilateral
Projections from the vestibular nuclei to the cerebellum through a bundle of fibers called this
Juxtarestiform body
Where is the juxtarestiform body located?
In the cerebellar peduncle
This type of dizziness is characterized by false sense of motion, possibly spinning sensation
Vertigo
This type of dizziness is characterized by feeling off balance or wobbly
Disequilibrium
This type of dizziness is characterized by feeling of losing consciousness or blacking out
Presyncope
The Dix-Hallpike positioning test is for this
Vertigo - distinguishes between central and peripheral causes
(vestibular functioning)
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Onset of nystagmus is delayed 2-5s
Peripheral
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Onset of nystagmus/vertigo can be immediate
Central
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Nystagmus does not change direction
Peripheral
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Nystagmus can change direction
Central
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Nystagmus can be observed without vertigo
Central
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Nystagmus and vertigo adapt if the test is repeated within ~30 s
Peripheral
Does this describe the result of Dix-Hallpike positional testing for central or peripheral vertigo causes:
Adaptation is not observed
Central
This is the most common cause of recurrent vertigo
Not associated with hearing loss or tinnitus
Benign positional vertigo
Benign positional vertigo is thought to result from this
Cuprolithiasis
(debris within the cupula part of the semicircular canals - possibly dislocations of the otoliths)
This condition that can cause vertigo involves an increase in endolymphatic fluid pressure
Meniere disease
Is benign positional vertigo associated with hearing loss or tinnitus?
No
Is Meniere disease associated with hearing loss or tinnitus?
Yes
Meniere disease is due to an increase in this pressure
Endolymphatic fluid
This cause of vertigo involves the presence of horizontal nystagmus during the attack; fast phase is to opposite ear
Meniere disease
Inflammation of the labyrinth due to bacterial, viral, or toxic substances (alcohol, quinine, salicylates)
Symptoms similar to Meniere disease
Labyrinthitis
Is Labyrinthitis associated with hearing loss or tinnitus?
Yes
Does a unilateral or bilateral labyrinthectomy give rise to nystagmus?
Unilateral
Predominantly horizontal nystagmus to the opposite side
(bilateral does not give rise to nystagmus)
Is Internuclear ophthalmoplegia caused by a lesion of the ascending or descending MLF?
Ascending
(between pons and midbrain)
Does acoustic schwannoma cause unilateral or bilateral loss of hearing, tinnitus and vertigo
Unilateral
The caloric test is used to test vestibular system function, and elicits this reflex
Vestibulo-ocular reflex (VOR)
This mass that arises in vestibular nerve of CN VIII has a lack of response to caloric stimulation
“Dead labyrinth”
Acoustic schwannoma
In the caloric test on an intact brainstem, do eyes move fast to the same or opposite side of cold water?
Opposite
(“COWS”)
In the caloric test on an intact brainstem, do eyes move fast to the same or opposite side of warm water?
Same
(“COWS”)
In the caloric test on a comatose patient, do eyes move slow to the same or opposite side of cold water?
Same
In the caloric test on a comatose patient, do eyes move slow to the same or opposite side of warm water?
Opposite
In a caloric test on a comatose patient, this movement will be absent
Fast movement
(so slower eye movement is assessed during the test)
