Week 5.7 Vestibular DD Exam

Question 1

what must you always assess first

Answer 1

oculomotor exam

Question 2

what are tests for peripheral dysfunction

Answer 2

spontaneous nystagmus 
gaze-evoked nystagmus 
head shaking nystagmus
head thrust 
dynamic visual acuity 
Dix- hallpike 
valsalva

Question 3

what are test for central dysfunction

Answer 3

spontaneous nystagmus 
smooth pursuit 
saccadic eye movements 
vergence 
dynamic visual acuity 
VOR cancellation

Question 4

what is the difference between visual fixation and fixation removed

Answer 4

visual fixation: you do things in ambient light, and the patient has to fixate

fixation removed is when they don’t fixate, so you use something like a fresnel lens or goggles.

Question 5

when testing nystagmus, do you use natural light or goggles

Answer 5

goggles

Question 6

when doing the Dix hall pike, goggles or ambient light

Answer 6

goggles

Question 7

when doing the VOR cancellation and DVA ambient or goggles

Answer 7

ambient light

Question 8

what do you look for when testing nystagmus

Answer 8

you are looking of the abnormal beating, and what kind of fast and slow beating there is

Question 9

what happens if nystagmus is observed in ambient light (with abnormal smooth pursuit, saccadic eye movements and abnormal VOR cancellation)

Answer 9

they may have a known neurologic condition, like a stroke or TBI, to they have a central vestibular dysfunction that needs to be referred out

Question 10

what is the likely cause of nystagmus is observed with goggles

Answer 10

may have an acute peripheral hypo function or they have something central going on.

Question 11

what are you looking for when you are testing smooth pursuit and convergence

Answer 11

you are looking for whether or not it is bumpy, and if they eyes can actually come together to look at the nose and when they get double vision

Question 12

what happens if there is abnormal smooth pursuit

Answer 12

saccadic intrusions and not smooth movement.

Question 13

what happens if there is abnormal convergence

Answer 13

double Vision at greater than 3-4 inches away from the nose

Question 14

what happens if there is anything abnormal with smooth pursuit or convergence

Answer 14

a central issue

Question 15

how do you test saccadic eye movements

Answer 15

you hold the patients head, and ask them to look between two targets. check if they are hitting the target or over or under shooting, or need many tried to actually get there

Question 16

what is normal and abnormal saccadic movements of the eyes

what diagnosis

Answer 16

normal: hits the target with 1-2 movements and vert minimal symptoms
abnormal: multiple movements to reach the target, and over and undershooting the target.

central issues

Question 17

how do you test VOR

Answer 17

have the patient extend their arm, watch their thumb, and rotate their head and arm at the same time while watching the target

Question 18

what is VOR cancellation

Answer 18

VOR is the ability to move the eyes equal and opposite to a head motion, and keep the image stable on the retina. So when you cancel it out, you want everything to move together

Question 19

what is abnormal VOR cancellation and what might it mean

Answer 19

there is central dysfunction

the eyes can’t stay on the target, or they get dizzy

Question 20

what is gaze evoked nystagmus.

Answer 20

with goggles, you ask the patients to move the eyes in all directions, and look for nystagmus when they hold each position.

Question 21

TF: always go to end range when testing gaze evoked nystagmus

Answer 21

false, don’t

Question 22

how does nystagmus from a peripheral lesion look

Answer 22

direction FIXED nystagmus, the eyes beat in the same direction, no matter which way the patient looks

Question 23

what does nystagmus from a central lesion look like

Answer 23

the direction is changing nystagmus. like the eyes might beat up when looking up, but beat down when looking down

Question 24

how do you test head shaking nystagmus

Answer 24

have them close their eyes, have goggles on, 30 degrees cervical flexion, rotate their head 20 times, look at them after 20 and observe nystagmus.

Question 25

what is a positive head shaking nystagmus test

Answer 25

the nystagmus will beat toward the intact side, and the fast phase is towards the intact side. SO THE CONTRALATERAL SIDE HAS THE HYPO-FUNCTION

Question 26

a positive head shaking nystagmus usually coincides with…

Answer 26

positive head thrust test and a history of unilateral hypo function

Question 27

how do you do a head thrust test

Answer 27

fixate the patients eyes on a target like your nose, and hold in 30 degrees cervical flexion, and quickly rotate them 30 degrees. with eyes on target in random order.

Question 28

how do you interpret a head thrust test

Answer 28

there is a positive test when there is a delay in returning the the target, and the delay occurs on the impaired side

Question 29

what does a positive head thrust test mean it could be

Answer 29

unilateral or bilateral peripheral hypo function

Question 30

`what is a dynamic visual acuity test

Answer 30

read lowest line you can, move their head at 120 beats/min as they continue to read from the top to the bottom, and not the difference in which line they can read

Question 31

what does the DVA test

Answer 31

the VOR

Question 32

what is considered normal and abnormal for DVA

Answer 32

normal is 2 lines or less

abnormal is 3 lines or more

Question 33

what can an abnormal DVA mean

Answer 33

peripheral hypo function
central dysfunction
decreased VOR