Dizziness Flashcards
Balance is coordinated by streams of which systems?
Visual, Vestibular, Proprioceptive
T/F Semicircular canals are sensitive to linear accelerations
F
They are sensitive to angular accelerations
Otolithic apparatus is sensitive to linear accelerations
T/F The lateral semicircular canal is strictly on a horizontal plane
F
It is angulated at around 20-30 degrees
In what orientation does the lateral canal lie during caloric testing?
When in supine position during caloric testing, the head is elevated by 30 degrees, and the lateral canal lies VERTICALLY
T/F: In functional pairs of semicircular canals, one canal gets stimulated when another is inhibited
T
Describe the ampullopetal motion when head rotates to the right
On the right horizontal SCC,
fluid moves towards the
ampulla causing excitation
● On the left horizontal SCC, fluid moves away from the ampulla
causing inhibition
Describe the ampullofugal motion when the head bows down
The fluid in the left and right anterior SCC moves upward, away from the ampulla → ampulla becomes excited
● In the posterior SCC, fluid moves
towards the ampulla →
inhibition
HSC = fluid movement towards the ampulla causes _____
excitation
ASC = fluid movement towards the ampulla causes _____
inhibition
PSC = fluid movement away from the ampulla causes _____
excitation
What is the movement of the right ear fluid if the head does yaw motion to the right?
To the left towards the ampula = excitation
What is the movement of the left ear fluid if the head does yaw motion to the right?
to the right away from the ampulla = inhibition
What is the movement of the left ear fluid if the head does yaw motion to the left?
to the right towards the ampulla = excitation
What is the movement of the right ear fluid if the head does yaw motion to the left?
towards the right away from the ampulla = inhibition
T/F: Otolithic apparatus is a component of the Proprioceptive System
F - otolithic apparatus is a component of the vestibular system
T/F: Otolithic apparatus is made up of the utricle and saccule with maculae that are
approximately positioned parallel to each other
F
They are positioned PERPENDICULAR to each other
T/F: Utricle is same plane as the horizontal canal, wile the saccule is in the vertical parasagittal plane
T
Which otolithic apparatus component detects linear acceleration when one moves side to side?
Utricle
Which otolithic apparatus component detects linear acceleration when one moves front to back?
Utricle
Which otolithic apparatus component detects linear acceleration when one moves up and down?
Saccule
T/F: Semicircular canals: angular acceleration :: otolithic apparatus: linear acceleration
T
This nuclei processes and integrates vestibular and non-vestibular information
Vestibular nuclei
It processes visual and spinal afferents for visuospatial orientation
The following are systems included in maintaining balance, except:
Eyes
Vestibular labyrinth
Cortex
Cerebellum
Muscles
Joints
Brainstem
Spinal Cord
Spinal cord
When doing slow head movements, _______ reflex is used
Optokinetic reflex
When doing fast head movements where you have to recognize where is up, down left, right, _____ reflex is used
Vestibuloocular reflex
How does vestibulospinal reflex in elderly work?
The vestibulospinal reflex in the elderly is decreased. This means that they do not have much reflex to adjust their muscle tone in response to changes in head movements for stability.
How does the vestibulospinal reflex work?
The vestibular system in the inner ear detects head movements -> sends signals to the spinal cord to activate muscles -> gait stability and coordination
What is the subjective disturbance of integrity caused by contradictory sensory information processing or impaired central processing?
Dizziness
T/F: Impaired central processing can be caused by metabolic or circulatory abnormalities, infection, trauma, or alcohol intoxication
T
4 Types of Dizziness
Presyncope
Lightheadedness
Disequilibrium
Vertigo
Rotary movement in vertigo involves the _____
semicircular canals
Body tilt or impulsion in vertigo involves the _______
saccule or utricle
Dizziness with duration of seconds could be:
Benign paroxysmal positional vertigo
Dizziness with duration of minutes to hours could be _______
Meniere’s Disease
Dizziness with duration of days to weeks could be_________
Vestibular neuronitis
what is the SNNOOP approach?
Systemic, neurologic, neck, otolaryngologic, ophthalmologic, psychatric
Romberg’s, Unterberger Tests are examples of ___________
Vestibulospinal Test (Neurologic Exam)
T/F: The vestibular disorders lead to a directional instability on the side of the affected vestibular organ
T
T/F Vestibular exams are usually done first in physical examination for dizziness
F: it is done last as it may provoke vertigo
T/F The corrective saccade indicates a deficient VOR on the opposite side of the head turn, indicating a peripheral vestibular lesion on the opposite side
The corrective saccade indicates a deficient VOR on the same side of the head turn, indicating a peripheral vestibular lesion on the same side
Conjugated, coordinated eye movement on an axis
Nystagmus
Which indicates direction, slow or fast phase nystagmus?
Fast phase nystagmus
This gaze-evoked nystagmus is due to toxicity from barbiturates, phenytoin and alcohol. It is present at rest
Spontaneous nystagmus
Common provocative measures for nystagmus
Head shaking, Positional Testing, Dix-hallpike maneuver
What part of the vestibular system is tested by positional testing?
Lateral Semicircular canal
What part of the vestibular system is tested by the Dix-hallpike maneuver?
Posterior semicircular canal
Most commonly used and easiest test to assess BPPV
Dix Hallpike Maneuver
Positive Dix hallpike maneuver indicative of BPPV on the RIGHT will present as a clockwise/counterclockwise torsional movement of the eyes
Counterclockwise
Positive Dix hallpike maneuver indicative of BPPV on the LEFT will present as a clockwise/counterclockwise torsional movement of the eyes
clockwise
Caloric Testing stimulates which part of the vestibular system?
lateral semicircular canal
Triad for Meniere’s Disease
Hearing Loss, Tinnitus, Ear Fullness
T/F Vestibular migraine is a central problem that behaves as a peripheral vestibular disorder
T
T/F Vestibular neuritis, similar to meniere’s disease, have horizontal or horizontal-torsional nystagmus
T
T/F Bilateral vestibular loss have up beating, torsional nystagmus
F: It has no nystagmus as both L and R peripheral vestibular apparatus have failed to function properly
Faster-acting anti-vertigo drugs
Cinnarizine
Dimenhydrinate
Meclizine
T/F: Treatments of BPPV aim to reposition the otoliths back to its original position in the UTRICLE
T
This should always be a differential diagnosis when faced with patient complaining of imbalance
Neural Vestibular Disorder
