Week 1- Vestibular Dysfunction: Examination Flashcards
PART 1: PATIENT REFERRAL AND LAB TESTING
PART 1: PATIENT REFERRAL AND LAB TESTING
Misdiagnosis is VERY common and is often referred for ________.
-Dizziness
What lab tests can be performed to help with diagnosing and treating vestibular patients?
- Audiogram
- ENG/VNG, Caloric testing
- Vestibular Evoked Myogenic Potential (VEMP) testing
What are the 3 main things that audiograms will give us information on?
- Auditory Asymmetry
- Retrocochlear Pathology
- Ear Canal and Tympanic Membrane integrity
Audiograms are largely used with vestibular patients for what reason?
-Used as screening tool to rule out any auditory pathology that may mimic vestibular pathology.
- Auditory asymmetry indicates the possibility of __________ vestibular or __________ _______ pathology.
- What are some examples?
- Peripheral Vestibular or Auditory Nerve Pathology
- Meniere’s Disease, Acoustic Neuroma, Perilymph Fistula, Labyrinthitis
- Retrocochlear pathology refers to site of lesion at the CN ____, ____________ angle, or CN ____ nerve root.
- Retrocochlear pathology presents with unilateral __________ hearing loss and impaired ______ recognition.
- What are some examples?
- CN VIII, cerebellopontine angle, or CN VIII nerve root
- sensorineural, speech
- Acoustic Neuroma, MS, variety of brainstem lesions
ENG and VNGs aren’t done as commonly as audiograms but specifically looks at the integrity of what?
-VOR integrity
What is the difference between ENG and VNG?
The way they measure VORs. ENG looks at muscular activity of extraoccular movements while VNG measures eye movement.
- ENGs and VNGs also allow us to look at what subtest?
- What is this?
- Caloric Testing
- Cold water is squirted into ear canal to evaluate integrity of unilateral vestibular apparatus.
Caloric testing is a comparative exam of what canal?
-Horizontal Canal
Describe what happens with caloric testing of the L ear normally.
- Elicits cooling effect on canal which affects endolymph inside which reduces activity of said canal.
- By inhibiting our L ear the brain thinks the head is moving to the right.
- VOR kicks in gear and moves eyes left but recognizes that the head isn’t moving and corrects back to right. (NYSTAGMUS)
What happens when warm water is used with caloric testing of the L ear normally?
-Warm water excites that side and will cause the opposite response.
What is a good way to remember caloric testing?
COWS
-COLD irrigations generate nystagmus in OPPOSITE direction, WARM irrigations in the SAME direction function bilaterally
What will we see with caloric testing with vestibular pathologies involving horizontal canal?
Blunted response unilaterally
-Significant Asymmetry = ~25% difference in peak slow component eye movement velocities obtained bilaterally.
What are Vestibular Evoked Myogenic Potentials (VEMP)?
-Short latency muscle reflexes typically recorded from the neck (cVEMP) or eye (oVEMP) muscles with surface electrodes in response to loud sounds.
What does cVEMP evaluate the integrity of?
-Otoliths (specifically saccule)
What muscle does the saccule project down to specifically?
-Sternocleidomastoid (SCM)
How does abnormal saccule function present when performing cVEMP?
- No muscular response (relaxation) to sound
- Asymmetrical response R vs L
How does structural abnormality present when performing cVEMP?
-Evoked response from softer sound waves (as sound turns down, SCM stays inhibited)
PART 2: SUBJECTIVE INTERVIEW
PART 2: SUBJECTIVE INTERVIEW
What do we want to do first in the systems review when assessing for vestibular dysfunction?
-Rule out other causes of vestibular-like symptoms.
More than 80% of the information needed to identify a specific vestibular diagnosis is made when?
-Subjective History/Patient Interview
What are (4) things that you can ask during a subjective history to help narrow down “Dizziness” diagnosis?
- Type of dizziness/ description of symptoms
- Triggers/ Relieving Factors
- Onset/Duration
- Frequency
-And other associated symptoms
_________ presents with a false sense of self-motion, can be rotational or linear, is due to imbalances of toxic neural activity to vestibular cortex, and can be caused by peripheral or central vestibular damage.
-Vertigo
___________ presents with gaze instability and illusionary sensation that a stational visual world is moving, and can be seen with bilateral>unilateral vestibulopathy and central vestibular dysfunction.
-Oscillopsia
____________ presents with imbalance or unsteadiness while standing or walking. Common causes are visual changes, vestibular dysfunction, and proprioceptive deficits.
-Disequilibrium
____________ is also referred to as pre-syncope and is caused from brief decrease in blood flow to the brain.
-Lightheadedness
____________ is episodic dizziness, tiredness, pallor, diaphoresis, salivation, and N/V. It is induced by passive locomotion (car) OR motion in visual surroundings while standing still. It is caused by sensory mismatch between visual and vestibular system.
Motion Sickness
What are the RED FLAGS with vestibular pathologies? (9)
- Severe headache
- Rapid hearing decline
- Dysarthria
- Discoordination
- Diplopia
- Decreased mentation & Urinary Incontinence
- Acute weakness
- Decreased consciousness
- Additional Cranial Nerve Dysfunction
PART 3: NYSTAGMUS AND OUTCOME MEASURES
PART 3: NYSTAGMUS AND OUTCOME MEASURES
What are the (4) main components of the vestibular examination?
- Auditory Screen
- Gaze Stabilization Assessment
- Cervical Dizziness Tests
- Balance and Postural Control Assessment
What is one of the most common S/Sx of vestibular dysfunction?
-Gaze Stability
What are some things to look at when assessing Gaze Stability? (9)
- Spontaneous Nystagmus
- Evoked Nystagmus
- Smooth Pursuit
- Saccades
- Optokinetics
- Dynamic Visual Acuity
- Head Impulse Test
- Head Shake Test
- Skew Deviation
- What is smooth pursuit?
- What is saccades?
- What is VOR?
- What is optokinetic?
- What is nystagmus?
- Smooth Pursuit = Voluntary slow following of a target.
- Saccades = Voluntary rapid repositioning of target.
- VOR = Involuntary eye stabilization in relation to head movement.
- Optokinetic = Involuntary, perceives motion in visual field, and supplements VOR to stabilize vision.
- Nystagmus = Involuntary eye movement which may cause the eye to rapidly move from side to side, up and down, or in a circle, and may slightly blur vision.
________ is an abnormal visual finding that can occur spontaneously.
-Nystagmus
- Nystagmus is a repetitive, to- and fro- movement of the eyes characterized by a _____ and _____ phase of movement.
- It is caused by imbalance between vestibular apparatus signaling and defined by the direction of the _____ phase of movement.
- fast and slow
- fast
- Nystagmus is the ________ diagnostic indicator used in identifying most peripheral and central vestibular lesions.
- It can be ___________ and can lead to vertigo, oscillopsia, and/or abnormal head positioning.
- primary
- asymptamotic
Are vertical and horizontal nystagmus the only forms?
No, can sometimes see torsional nystagmus.
What are the 2 major ways we classify nystagmus?
- Spontaneous
- Evoked
What is the 5% of nystagmus that may be normal?
When bringing to end range and hanging there, can see some nystagmus in normal.
____________ Nystagmus is the onset of nystagmus without any cognitive, visual or vestibular stimulus and occurs in the absence of any purposeful eye or head motion.
-How does this happen?
- Spontaneous
- When one side is not working correctly it will present as inhibited and cause an imbalance (Ex: R side inhibited, reflex thinks head is moving to L, eyes correct and go R).
What are the (3) primary things that define peripheral spontaneous nystagmus?
- Mixed horizontal/torsional (same direction).
- Presents with acute lesions, rarely w/ chronic stable lesions.
- More prominent with fixation removed.
What are the (3) primary things that define central spontaneous nystagmus?
- Vertical/torsional.
- Acute or chronic.
- More prominent w/ fixation present.
- How do we test for fixation removed/present?
- What do we do if we don’t have these items?
-Visual fixation blockers.
(Frenzel Lenses, Video Infrared Goggles)
-Private treatment room w/ lights off and shining light into patients eyes.
What are 2 outcome measures used?
- Motion Sensitivity Quotient
- Dizziness Handicap Inventory
- What is Motion Sensitivity Quotient (MSQ)?
- With this, symptoms are scored off of ________ and ________.
- Objective examination tool bringing patient through 16 potential provocative head/body movements that can elicit motion sensitivity.
- intensity and duration
What is the scoring for MSQ?
- Mild Vestibular Dysfunction = 0-10
- Modderate Vestibular Dysfunction = 11-30
- Severe Vestibular Dysfunction = 31-100
- Dizziness Handicap Inventory is a 25-item self-assessment designed to evaluate ______-__________ handicap from dizziness.
- It is on a 0-100 scale with _______ scores indicating higher perceived handicap.
- What are the 3 subscales of questions?
- self-perceived
- higher
- physical, emotional, functional
- What is the scoring for the Dizziness Handicap Inventory?
- What is the MCID?
- Mild = 0-30
- Moderate = 31-60
- Severe = 61-100
-MCID = 18
