Lesions and causes Flashcards
Scotoma of motion
damage to MT/V1 or V5 (global/peripheral)
see motion in only one direction
damage to MST/V3 (lobal motion)
directional pursuit deficit
damage to MST/V3
ipsiversive horizontal eye fields
Frontal eye fields
Dorsal vermis if hypometric
vertical pursuit deficit
NRTP
This breaks the vertical = midbrain rule!
contraversive horizontal pursuit deficits + hypermetria
fastigial nuclei
dysfunction of VOR and pursuits
cerebral disease
dysfunction direction is same side as hemisphere w/ damage (ipsiversive)
mild pursuit and VOR cancellation deficits
one side of ventral paraflocculus (in cerebellum)
severe deficits in pursuits and VOR
bilateral lesions of both ventral paraflocculus (VPF) and flocculus
lesioned cerebellum structure that causes no effect on pursuit
bilateral flocculus (since lesions cancel each other)
opsoclonus, ipsiversive horizontal pursuit deficits
dorsal vermis
vergence control location
cerebrum (middle temporal lobe)
Brain lesion that would cause: Smooth vergence (NPC) deficits
MST/V3 (cerebrum)
Brain lesion that would cause: jump vergence and saccade deficits
MT/V5
voluntary vergence control center
frontal eye fields
smooth, pursuit-like vergence, NPC
parietal eye fields
undershoots
dorsal vermis
lesion in the dorsal vermis causes:
DI at far (esodeviation)
fastigial nuclei lesion
cause CI by activating divergence at near
NRTP (pon lesion causes:
inappropriate divergence (aka CI)
type of nystagmus caused by vision loss
monocular APN (worse in eye w/ worse BCVA)
called Heimann-Bielschowsky
gaze-evoked nystagmus
leaky neural integrator: medial vestibular nuclei, NPH (pons) or INC (vertical)
Cerebellum responsible for integration
horizontal gaze-evoked nystagmus
neural integrator: nucleus prepositus hypoglossi (NPH) in pons
vertical gaze-evoked nystagmus
neural integrator: interstitial nucleus of Cajal (INC) in the midbrain
INO
MLF demyelination or stroke
Brun’s nystagmus
cerebellar pontine angle (CPA)
Lateropulsion
dorsolateral medulla
medulla’s olivary nucleus
afffect CN9: glossopharyngeal –> oculopalatal tremor
red nucleus
in the midbrain, control of the EOMs and soft palate (myoclonus)
dentate nucleus
cerebellum
affect control of the EOMs and soft palate
Location of the cause of oculopalatal tremor
Myoclonic triangle of guilain and Mollaret
contains red nucleus, dentate nucleus, olivary nucleus
Medial medullary syndrome
vertical nystagmus (downward drift, upgaze nystagmus)
Dejerine Syndrome
is a lingual palsy, and a medial medullary syndrome
INO lesion location
MLF
NRTP (Nucleus recticularis Tegmenti pontis) Lesion
vergence impaired w/ a horizontal gaze palsy leading to CI and DI