Examination of Cerebellar Dysfunction Flashcards
what are the different functions of the cerebellum?
- motor coordination
- balance
- saccades (ability to track moving objects)
what happens if there are any masses that pushes down on the cerebellum or brainstem?
sudden INC in ICP
what are the lcoaitons of the parts of the cerebellum?
superior cerebellar peduncle = midbrain
middle cerebellar peduncle = pons
inferoir cerebellar peduncle = medulla
what re the 4 cardinal signs of cerebellar dysfunction?
ataxia
tremors
hypotonia
asthenia
what supplies blood to the cerebellum?
posterior circulation -> basilar arery
what are initial signs of cerebellar dysfunction?
dizziness, vertigo or imbalance due to affectation of the vestibular nuclei
what is the cerebellar tract of outputs from the L cerebellar hemispheres?
goes to the Inferior olivary nucleus -> dentate nucleus -> thalamus -> motor cortex -> crosses 2x compared to CST -> ipsilateral manifestation
what is the cerebellar tract of outputs from the intermediate cerebellar hemisphere?
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
what is the cerebellar tract of the outputs from the cerebellar vermis & flocculonodular lobe?
goes thru Fastigial nucleus (M motor systems)
Flocculonodular lobe & inferoir vermus -> direct projections to vestibular nuclei -> influence balance & vestibulo-ocular control
what are the diff examinations of the cerebellum?
gait
ataxia
dysdiadochokinesia in the upper ex
dysmetria in the lower ex
nystagmus
dysmetria in the upper ex
what is done in checking for nystagmus?
hold the gaze laterally & vertically to check for JERKY EYE MOVEMENT
In checking horizontal nystagmus, what is done?
ask px to look R or left?
what is the most common cause of horizontal nystagmus?
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
in checking for vertical and torsional nystagmus, what is done?
ask px to look up & down
what are the impairment of Vestibulo-ocular reflex?
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
what is dysmetria?
inability to calculate disrtances
what are the diff techniques used to diagnose dysmetria?
finger-nose-finger test
precision finger tap
loss of check-holes test
arm pulling test
in finger-nose-finger test, what is the presentation of dysmetria?
wiggly motion or they completely miss the target
in loss of check-holmes test, what is positive for cerebellar lesion?
overshooting oscillation: arm oscillates up and down & doesnt end up at the same level of other arm
what test assesses the ability to coordinate that the hand should not hit the face?
arm pulling test
(+) = when u let go, the px’s hand would hit his face without meaning to
what is done in Dysdiadochokinesia in the upper ex?
finger tapping = check for uncoordinated movement
what re the 3 tests done to check for dysmetria in the lower ex?
shin tap test
heel-to-shin test
foot tapping
what are positive signs of cerebellar lesion in Shin tap test & Heel-to-shin test?
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
what are the tests done to check for ataxia?
head tremors
truncal ataxia
romberg
what is indicated as positive signs of cerebellar problem in Rombergs test?
sways with eyes CLOSED = DCML pathway problem
sways with eyes OPEN = cerebellar problem
what are speech abnormalities in cerebellar px?
scanning speech
- irregular fluctation in both RATE & VOLUME
- robot talking
