Examination of Cerebellar Dysfunction

Question 1

what are the different functions of the cerebellum?

Answer 1

• motor coordination
• balance
• saccades (ability to track moving objects)

Question 2

what happens if there are any masses that pushes down on the cerebellum or brainstem?

Answer 2

sudden INC in ICP

Question 3

what are the lcoaitons of the parts of the cerebellum?

Answer 3

superior cerebellar peduncle = midbrain
middle cerebellar peduncle = pons
inferoir cerebellar peduncle = medulla

Question 4

what re the 4 cardinal signs of cerebellar dysfunction?

Answer 4

ataxia
tremors
hypotonia
asthenia

Question 5

what supplies blood to the cerebellum?

Answer 5

posterior circulation -> basilar arery

Question 6

what are initial signs of cerebellar dysfunction?

Answer 6

dizziness, vertigo or imbalance due to affectation of the vestibular nuclei

Question 7

what is the cerebellar tract of outputs from the L cerebellar hemispheres?

Answer 7

goes to the Inferior olivary nucleus -> dentate nucleus -> thalamus -> motor cortex -> crosses 2x compared to CST -> ipsilateral manifestation

Question 8

what is the cerebellar tract of outputs from the intermediate cerebellar hemisphere?

Answer 8

either of the 2:

goes to interposed nuclei -> rubrospinal tract -> double crossing before inrerposed nuclei & to the tracts

goes to CL ventrolateral thalamic nucleus -> moroe, supplementary motor, premotor context -> L CST -> L motor systems

Question 9

what is the cerebellar tract of the outputs from the cerebellar vermis & flocculonodular lobe?

Answer 9

goes thru Fastigial nucleus (M motor systems)

Flocculonodular lobe & inferoir vermus -> direct projections to vestibular nuclei -> influence balance & vestibulo-ocular control

Question 10

what are the diff examinations of the cerebellum?

Answer 10

gait
ataxia
dysdiadochokinesia in the upper ex
dysmetria in the lower ex
nystagmus
dysmetria in the upper ex

Question 11

what is done in checking for nystagmus?

Answer 11

hold the gaze laterally & vertically to check for JERKY EYE MOVEMENT

Question 12

In checking horizontal nystagmus, what is done?

Answer 12

ask px to look R or left?

Question 13

what is the most common cause of horizontal nystagmus?

Answer 13

Benign Positional Paroxysmal vertigo
- dizziness with sudden head movements
- problems in middle ear or balance mech
- peripheral: ear-induced
- central: lesion in the cerebellar hemisphere

Question 14

in checking for vertical and torsional nystagmus, what is done?

Answer 14

ask px to look up & down

Question 15

what are the impairment of Vestibulo-ocular reflex?

Answer 15

Saccades = rapid, ballistic movements of the eyes that abruptly change the point of fixation

ask px to focus on ur nose while holding the patient’s face
- normal VOR: eyes are fixed on examiner’s nose
- abnormal VOR: eyes are moving to the direction of where the head is turned

Question 16

what is dysmetria?

Answer 16

inability to calculate disrtances

Question 17

what are the diff techniques used to diagnose dysmetria?

Answer 17

finger-nose-finger test
precision finger tap
loss of check-holes test
arm pulling test

Question 18

in finger-nose-finger test, what is the presentation of dysmetria?

Answer 18

wiggly motion or they completely miss the target

Question 19

in loss of check-holmes test, what is positive for cerebellar lesion?

Answer 19

overshooting oscillation: arm oscillates up and down & doesnt end up at the same level of other arm

Question 20

what test assesses the ability to coordinate that the hand should not hit the face?

Answer 20

arm pulling test
(+) = when u let go, the px’s hand would hit his face without meaning to

Question 21

what is done in Dysdiadochokinesia in the upper ex?

Answer 21

finger tapping = check for uncoordinated movement

Question 22

what re the 3 tests done to check for dysmetria in the lower ex?

Answer 22

shin tap test
heel-to-shin test
foot tapping

Question 23

what are positive signs of cerebellar lesion in Shin tap test & Heel-to-shin test?

Answer 23

Shin tap test
- (+): px misses teh spot & taps disrhythmically

Heel-to-shin test
- (+): heel would zigzag on the way down or they can’t control or stay on the track, no graceful movement

Question 24

what are the tests done to check for ataxia?

Answer 24

head tremors
truncal ataxia
romberg

Question 25

what is indicated as positive signs of cerebellar problem in Rombergs test?

Answer 25

sways with eyes CLOSED = DCML pathway problem
sways with eyes OPEN = cerebellar problem

Question 26

what are speech abnormalities in cerebellar px?

Answer 26

scanning speech
- irregular fluctation in both RATE & VOLUME
- robot talking