Audiology Praxis Review (Vestib) Questions with Complete Verified Solutions 2024/2025, Exams of Health sciences

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Audiology Praxis Review (Vestib)

Questions with Complete Verified

Solutions 2024/

ENG stands for Electronystagmography VNG stands for Videonystagmography 3 reasons to pick ENG over VNG

1. patient has claustrophobia 2) patient has dark areas around eyes (permanent makeup/ injury) 3) patient is under age of 6 and VNG goggles don't fit on small head. Upward trace deflections represent _______ eye movement rightward Downward trace deflections represent ______ eye movement. leftward T/F: The VNG/ENG evaluation is a series of subtests performed to assess portions of the peripheral and central vestibular systems. True T/F The evaluation of central vestibulo-ocular pathways are restricted and evaluation of peripheral vestibular systems is quite thorough. False. Central evaluation is thorough. Peripheral evaluation usually targets only horizontal semicircular canal and restricted information from vertical canals and otolith organs. What are the 5 main subtests during a ENG/VNG?
2. Oculo-motor
3. Spontaneous nystagmus
4. Rapid Positioning (Dix-Hallpike)
5. Positional nystagmus
6. Caloric irrigations VOR stands for ____________ Vestibulo-ocular reflex

Which of the 5 main subtests should be evaluated by direct examination and not by post hoc recordings? Dix-Hallpike What are the transducers of auditory and vestibular sensory epithelia? The auditory and vestibular sensory epithelia are hair cells. What are the two types of vestibular sensory epithelia? the cristae ampullares and the maculae. How do the sensory epithelia convert and send stimuli? The cilia on each hair cell in the vestibular system are bound together to form the ciliary tuft. When the tuft is bent towards the kinocilium, potassium channels are opened and the hair cells are excited, releasing neurotransmitters to activate the nerve endings on the hair cells. This propogates action potentials along cranial nerve VIII. Explain the differences between the two types of vestibular hair cells Type I:

• Flask shaped
• Large synaptic endings called calyces (singular calyx) Type II:
• Columnar shaped
• Bouton-type terminals synapsing onto their base Explain the difference between the two types of cilia. Stereocilia:
• 100 of these on a single cell that are each anchored in the cuticular plate Kinocilium
• Only one per hair cell
• Longer than the stereocilia and has no actin
• Eccentrically located, near the cuticular plate
• Polarizes the apical surface of the hair cell What happens when the ciliary tuft is bent in the direction of the kinocilium? If it is bent towards the kinocilium, potassium channels open and the hair cell is excited. What happens when the ciliary tuft is bent away from the direction of the kinicilium? If it is bent away from the kinocilum, the cell is inhibited. What movement stimulates the saccule? The saccule is stimulated by vertical linear acceleration. What movement stimulates the utricle? The utricle is stimulated by horizontal linear acceleration or static head tilt.

Explain what makes up the otolithic membrane and how it responds to different movement. Crystals add weight to the otolithic membrane and enable it to respond to two types of stimuli:

• Tilting of the head: gravity pulls on the membrane and bends the ciliary tufts
• Rapid linear acceleration or deceleration of the head: inertia delays the movement of the heavy otolithic membrane and causes it to pull on the cilia What does the cupula respond to? Cupula responds to angular acceleration and deceleration (head moves relative to the rest of the body) What does the macula respond to? Macula responds to linear movement (head and body move together) What is complementary coding Ducts on one side of the head are paired with those on the other side of the head. Where does the vestubular division of the vestibulocochlear nerve enter the brainstem? Cerebellopontene angle (CPA) What does the superior vestibular nerve innervate? The horizontal and anterior SCC ans well as the utricle. What does the inferior vestibular nerve innervate? The posterior SCC and the saccule. From where does the vestibular end organ blood supply arise? Through the labyrinthine artery which arises from the anterior inferior cerebellar artery. What system synergizes all motor movements? The cerebellum. What is the vestibulocollic reflex? causes your head to rotate in one direction when your body rotates in the oposite direction. What is the vestibulospinal reflex? Causes postural adjustments and keeps you from falling over when you lean too far to one side. What causes nausea when the patient is dizzy? Pathological changes, rapid spinning, or chronic rhythmic movements can overstimulate the vestibular system and result in nausea. What can the vestibular motor system influence? Can influence the motor system in that it can cause motor responses that are reflexive. What is the main purpose of the oculomotor system? To position the eyes so that targets of interest fall on the fovea. What are the six orbital muscles and the purpose of each? What are their complementary pairs? Medial and Lateral Recti: for horizontal eye movement Superior and Inferior Recti: for vertical movement Superior and Inferior Oblique: for complex movements What does damage to the oculomotor nerves and nuclei cause?

Damage to the nerves and nuclei causes one eye to have slow or limited eye movement, It commonly causes diplopia and ocular misalignment. Which cranial nerves innervate which ocular muscles? CN III (oculomotor nerve) is the only nerve that innervates multiple muscles - the superior and inferior recti, the medial rectus, and the inferior oblique. It also innervates the pupilomotor and eyelid muscles. CN IV (trochlear nerve) innervates the superior oblique muscle CN VI (abducens nerve) innervates only the lateral rectus What is rebound nystagmus? It is a response to prolonged eccentric gaze holding. When the eyes are brought back to the center, they drift for several seconds in the direction of previous gaze holding. What are Saccades? Saccades are rapid eye movements. What is the purpose of a saccade? Their purpose is to bring a point of regard into the fovea. What typically causes saccadic disorders? Almost all clinically important saccadic disorders are due to brainstem or cerebellar lesions. What is dysmetria? What typically causes these? Saccadic inaccuracy. Caused by cerebellar lesions. What is hypermetria? What typically causes these? Saccades that overshoot. Caused by cerebellar disease, damage to the fastigial nucleus. What is hypometria? What typically causes these? saccades that undershoot. Caused by lesions of the cerebellar dorsal vermis. What is pulsion? What typically causes these? Saccades that exhibit unintended off-axis movement. Caused by cerebellar lesions. What is pursuit/ tracking? It is the ability to move the eye at the same speed as a target so that it remains stable on the retina. What is iptokinetic nystagmus? What is its purpose? OKN is a tracking response. It is the eye movement that is elicited by tracking of a field, rather than a discrete target. Its purpose is to stabilize an entire visual field. What is fixation? It is the process by which the brain suppresses internally generated eye movements. What are square wave jerks? A common type of nystagmus found during fixation that are unintended saccadic eye movements. The waveform of the eye movement trace resembles a rectangle. What is congenital nystagmus? It is a miswired fixation system in which nystagmus is present at birth. What repairs and calibrates the oculomotor neural circuitry?

The cerebellum. What is the difference in vertigo versus nonvertigo?

• vertigo is the true rotational movement of self or surroundings.
• Nonvertigo includes lightheadedness, unsteadiness, presyncope, and imbalance. Asymmemetry in vestibular input can cause what sensation? The illusionary sense of movement, nystagmus, or dizziness. What are the differences between central and peripheral vertigo? Central- involves dysfunction of the vestibular nuclei, cerebellum, or the oculomotor vestibulospinal and proprioceprive pathways. Peripheral- dysfunction of the end organs or vestibular nerve. What is presyncope and what causes it? It is the uncomfortable, light headed sensation preceding fainting. It is caused by hypotension (low blood pressure), reduced cardiac output, and vasovagal attacks. What is a vasovagal attack? What does it cause? Vasovagal attack: excessive sensations of fear, anxiety, or disgust leads to reduction in cardiac output, and leads to dizziness, pallor, and nausia. Causes presyncope. What is disequilibrium? What role in vision does it play? DisequilibriumL slight dizziness or imbalance not related to head position or activity. Vision helps to maintain gaze and postural stability during movement, disequilibrium is worsened for those with vision impairments. WHat is hyperventilation and what are its symptoms? Hyperventilation is the most common cause of dizziness in young patients. Symptoms include: air hunger, palpitations, sweating, shaking, tremors, chest tightness, or paresthesias. WHat causes motion sickness? What are the symptoms? What helps? Motion sickness si the combination of dizziness and autonomic symptoms induced by movement. Symptoms include: nausea and vomiting. It helps to reduce the mismatch between the two systems (visual and vestib systems) What is and what causes ataxia? Ataxia is clumsy motion and unsteadiness due to a lack of coordinated muscle movement. Caused when there is a defecit in either the central nervous system or both vestibular systems. What are the 5 categories of dizziness?

1. Fleeting (> a second)
2. Short-lasting (few seconds or minutes)
3. Intermediate (20 min-several hours)
4. Long-lasting (2-3 hours to day/s)
5. Continuous (several weeks) What is BPPV? What are its characteristics?

The most common cause of vertigo characterized by a sudden onset of vertigo with no accompanying neurologic symptoms. Occurs exclusively with head movements. Which canal is most commonly affected by BPPV? The posterior canal. How is BPPV diagnosed? Diagnosed by preforming the Dix-Hallpike maneuver. What is sound-induced vertigo? What are two causes? The inner ear is susceptible to loud sounds or rapid changes in pressure due to a lack of normal bony cover of the inner ear. Caused by either superior canal dehiscence and perilymphatic fistula. What is Miniere's Disease? Meniere's is an abnormal accumulation of fluids of the inner ear. What are the characteristics of Meniere's? Episodic vertigo with nystagmus, fluctuating low frequency HL, unilateral tinnitus, and aural fullness. What are some treatment options for Meniere's? Controlling symptoms through stress reduction, low salt diet, mild diuretic, and surgery when symptoms are uncontrolled. Describe migraine headache and its relation to dizziness. WHat are some associated symptoms? What are some treatment options? Nearly 25-40% of patients with migraines report episodic vertigo. Symptoms include vertigo, auditory symptoms, photophobia, and phonophobia. Treatment includes avoiding triggers including stress and multiple dietary products and medication. Describe vestibular neuronitis including its possible etiology, symptoms, and treatment. VN is a dysfunction of one side of the peripheral nervous system without any associated auditory deficit. Etiology: related to a viral infection of the vestibular nerve. Symptoms include- vertigo lasting 1-3 days, often results in permanent unilateral vestibular weakness and disequilibrium with head movement. Treatment: acute treatment include antiemetics and sedatives, treatment aimed at stopping the inflammation, long term treatment includes vestibular rehabilitative therapy. Descrive labrynthitis including its possible etiology and symptoms. Labyrinthitis is an infection of the entire inner ear, includes hearing loss and tinnitus. May be viral or bacterial in origin. Etiology: can result from otitis media, meningitis, or systemic illness. Symptoms: acute in onset but usually self-limited with spontaneous resolution. Describe head trauma and dizziness. Minor trauma may result in dizziness through post-concussive vertigo, labyrinth may also be injured by temporal bone fracture. Describe cerebrovascular disease and dizziness including symptoms, risk factors, and treatment.

Altered posterior intracranial circulation supplying the vestibular system causing vertigo. SymptomsL vertigo, disequilibrium, visual disturbances, confusian, headaches, hearing loss, numbness, incoordination, or altered speech. Risk factors: transient ischemic attacks (TIA), strokes, vertebrobasilar insufficiency. Treatment: blood thinning with medicines. Describe medication and dizziness. Medication may cause injury to the vestibular system or alteration of neurotransmitters. Most common ototoxic meds are antibiotics and chemotherapeutic agents. What disorders are associated with single attacks and what disorders are associated with multiple attacks? Single: permanent vestibular injury such as labyrinthisis, vestibular neuronitis, strokes, multiple sclerosis, or traumatic injury. Multiple: BPPV, peripymphatic fistula, Meniere's disease, transient ischemic attacks, or psychiatric disease. What is a vestibular schwannoma? What are the symptoms? VS is a tumor on the cranial nerve 8. Symptoms: HF HL, tinnitus before vestibular complaints, can also cause facial numbness or weakness, incoordination, or ataxia. What are some neurologic symptoms associated with dizziness? Nausea, vomiting, photophobia, phonophobia, also includes muscle weakness, dysarthria, visual changes, hearing changes, parestheasis, altered level of consciousness, or ataxia. How would surgery cause dizziness? If the stapes prosthesis is too long, sounds may induce excessive pressure on the vestibule and cause dizziness. May experience vertigo similar to perilymphatic fistula if the defect in the oval window is not repaired. How can a balance system disability/ handicap affect an individual's physical and/or phychosocial function? It is an invisible handicap and it's unpredictability produces anxiety, depression, and panic that often isolates one from daily activities. Why should we preform formal quantitative measures for dizzy patients? What do these measures provide? Provides us with a method for determining the extent that contextual factors influence activity limitation. It also serves as a standardized outcome measure. Descrive the Functional Level Scale/ Who designed this measure? It was developed to address the disabling accompaniments of vertigo, a patient makes a single decision of which statement best reflects their current status. Designed by the American Academy of Otolaryngology (AAO).

Explain the Dizziness Handicap Inventory. A standardized measure of self-report activity limitation and participation restriction resulting from dizziness and unsteadiness. Describe the "Welcome to Medicare Visit." The visit includes an initial preventative physical exam (IPPE) that includes assessment of depression, hearing, activities of daily living, home safety, and an assessment of falls risk. What is the objective of the Risk of Falls Clinic? To identify those elderly people at greatest risk for falling by administering a set of evaluations aimed at the assessment of specific risk factors known to be associated with falling. List five known risk fall factors. Parkinson's disease. Osteoporosis. Heart disease. Diabetes. Postural hypotension. What are four age-related physiologic functions for postural control? Vision, somatosensory, vestibular, and muscle tone changes How is depression a risk factor for falling? Makes patients less aware of their environment. Medications can cause side effects. How is impaired vision a risk factor for falling? Makes it difficult for patients to identify edges that may result in falls. Visual acuity poorer than 20/50 can result in measurable decrements in postural control. Vestibular bedside evaluation are designed to evaluate what? Evaluate the vestibule-ocular reflex (VOR) and setibulospinal reflex (VSR). How do we test for spontaneous nystagmus? What should be recorded? What do these findings indicate? Specifically check that the patient has a full rage of movement of each eye. Have the patient fixate on a target that is approx 4 feet away. If nystagmus is notes, amplitude and direction of nystagmus should be recorded as well as the differences in the nystagmus between eyes (with and without vision) Indicate: acute peripheral disorders of the labyrinth or central nervous system disorder. When do we perform mental alerting tasks? Why? When vision is denied and the patient is sitting upright while examining the eyes for any SN. In order to help the patient fixate. When the head is accelerated, which is is associated with increased neural activity and which ear is associated with decreased neural activity? The leading ear assumes a level of increased neural activity. The nerve with the paired canal on the opposite side is associated with decreased neural activity. Unilateral loss of peripheral function causes what? Causes spontaneous nystagmus as the system attempts to visually track perceived rotation away from the side of lesion.

Which phase is used to describe nystagmus? Which phase is generated by the vestibular system? The fast phase is used to describe nystagmus, but the slow phase is generated by the vestibular system. With spontaneous nystagmus, patients report they are rotating __________ the intact side. Towards. What does the presence of spontaneous nystagmus demonstrate? May lead an examiner to suspect unilateral vestibular hypofunction, but need multiple tests to diagnose this. Explain the head-impulse test (HIT) What is a normal and abnormal test result? The patient is instructed to fixate on a target while the examiner grasps the patients head and guides it through a quick head turn. Examiner observes the patients eyes to confirm they remain stationary on the target. Normal: fixation is maintained on the target. Abnormal: abnormal catch-up saccade observed. During the HIT test, when the head is thrust in the direction of the impairment, what will be observed? An abnormal catch-up saccade, the eyes are trying to vixate again. Ability or inability of a patient to maintain fixation on a target during an extremely fast angular excursion of the head (HIT) can give the examiner some insight into what? Into the integrity of the lateral SCC ipsilateral to the direction of the head turn. What is the difference between the HIT and the caloric test? Calorics use temperature inputs. Caloric response is analogus to a rotational stimulus of 0.003 Hz and the HIT represents a high frequency movement characteristic of those in everyday life. Peripheral vestibular systems affect which frequency movement first? Low frequency spectrum. Explain the head shake test. What is active vs passive testing? What is seen with a positive test result? When the head is shaken vigorously for 10 to 30 cycles and then stopped, a transient vestibular nystagmus may emerge in patients with peripheral and central vestib disorders. Active: patient shaves their own head Passive: examiner shakes head for them Positive test results: can produce head shaking nystagmus (HSN). What is oscillopsia and what is its cause? The perception of objects bouncing or blurring when the head is moving. Can be caused by a deficit in the VOR. Explain the hyperventilation-induced nystagmus test. What is a normal and abnormal response?

Using goggles, the patient should be in a standing position and instructed to take deep, rapid breaths for 30 - 60 seconds. Normal: No nystagmus Abnormal: nystagmus (direction of fast phase is ipsilesional) Explain Romberg's sign. What does the test help distinguish? Decrease in postural stability when the eyes are closed. Distinguish patients with unsteadiness due to the proprioceptive anomalies in the lower extermities from those with vestibular system damage. Describe the Romberg test. What is a normal and abnormal result? What does it assess? Patient stands with eyes open and arms crossed- postural stability is evaluated, then compared to stability with eyes closed and arms crossed. Normal: Should not fall or increase in sway for 30 seconds Abnormal: increase in sway, stagger, fall. Assess function of the lower limb proprioceptive spinal reflex arcs. Describe the Fukuda Stepping test. WHat is a normal and abnormal result. Designed to identify presence of a peripheral vestibular system impairment. Arms extended 90 degrees, march in place for 50 steps. Normal: no significant deviation from starting position Abnormal: rotation or 45 degrees in either direction. What is the difference between bitemportal and monocular recording techniques? Bitemportal: a pair of electrodes on the outer canthus of each eye as well as a pair of electrodes above and below one eye. Monocular: allows for recording each eye movement separately. Electrode montage is similar to bitemporal but one electrode is added to both sides of the bridge of the nose. What are the advantages and disadvantages of the VNG system over the ENG system. Advantages: No physical contact with the cornea is required, avoids the use of electrodes, temporal resolution is sufficient for all but the fastest eye movements, measurements can be made without vision by obscuring outside light from the patient's view, recordings provide a means of documenting the presence of, and direction of, torsional eye movements Disadvantages: impossible to measure the eye movements with the eyes closed because the system requires direct visualization of the pupil and cornea to perform the necessary calculations for localization of gaze, goggles can be uncomfortable, cameras focus on makeup instead of pupil, patients that blink excessively make interpretation of results difficult, bulky goggles can make different positional tests difficult to maneuver What are the four principal ocular motor tests? Saccade testing Smooth pursuit tracking

Gaze stability Optokinetic nystagmus Saccadic testing is used to identify what? central brainstem or cerebellar lesions What are the three saccadic test measurement parameters? Velocity- speech in which the eyes move Accuracy- ability to closely approximate the target movement Latency- delay of the eye movement after the target has moved. Smooth pursuit tracking testing is used to identify what? Central brainstem or cerebellar lesions What are the three smooth pursuit test measurement parameters? Velocity gain- indirectly a measure of how sinusoidal the eye movement was in comparison to the target. Asymmetry- the percentage difference for velocity gain for the left or right eye moving rightward and leftward Phase angle- measure of how much the eye is lagging or leading the target. Gaze stability testing is used to identify what? central or peripheral vestib lesion What designations are made in gaze stability testing? As to fixation present or fixation removed, along with indications to the direction of the nystagmus beat. Explain the 3 degrees of gaze-evoked nystagmus. 1st- nystagmus present when gazing only in the direction of the fast phase. 2nd- nystagmus in the direction of the fast component and in primary. 3rd- nystagmus in the direction of the beat, primary, and while gazing away from the beat of the nystagmus. Gaze is the only oculomotor tests where the results can indicate what? peripheral or central lesion. What are the characteristics of central nystagmus? direction changing, pure vertical , or torsional nystagmus Nystagmus beats _______ the more active neural side. toward Square-wave jerks likely represent what? Cerebellar or upper motor neuron pathology. What are the four characteristics of congenital nystagmus?

1. history of ongoing eye movement
2. usually horizontal even in up or down gaze.
3. can be slowed with convergence
4. slow phase of the nystagmus will show as increasing in velocity.

What is cog wheeling? Classic saccadic disruptions to the attempt to move the eyes in a smooth manner when tracking the light bar What is the least useful of the oculomotor tests? OKN What are the otoliths stimulated by? linear acceleration Nystagmus with no vertigo indicates what? central nervous system involvement What is geotrophic and ageotrophic nystagmus? geotrophic- beating towards the earth ageotrophic- beating away from the earth What are some other causes of positional nystagmus? medications, CNS changes, age, migraine Fixation supression is expected with a _______ origin, while no fixation is expected with a _____ origin. peripheral, CNS