Vestibular and cerebellar disease Flashcards
What is appendicular ataxia?
Jerky, uncoordinated movement of the limbs as though each muscle were working seperately from the others
What is truncal ataxia?
Postural instability, wide based stance, gait instability, inconsistent foot positioning
What is the general definition of ataxia?
Neurologicalsigns of gross incoordination of muscle movements
Ataxia shows more clearly when they are walking or running?
walking
What are the three kinds of ataxia in terms of origin?
Sensory ataxia
Vestibular ataxia
Cerebellar ataxia
What kind of ataxia are the following clinical signs of?
Abnormal postural reactions
Limb paresis
Sensory ataxia
What are the components of the vestibular system?
The central vestibular nuclei
Vestibular portion of VIII (vestibulocochlear nerve)
Peripheral vestibular receptors
What are the clinical signs of vestibular ataxia?
Head tilt
Leaning, falling or rolling to one side
Abnormal nystagmus (fast away from the lesion)
Positional strabismus
Normal (peripheral) or abnormal (central) postural reactions
What are the clinical signs of cerebellar ataxia?
Wide based stance
Intetion tremors of the head
loss of balance/truncal sway
Dysmetric hopping
Ipsilateral menace deficits with normal vision
No limb paresis or proprioception deficits
Pendular nystagmus
What is the occulovestibular reflex?
Move the head from side to side, to start with keeps the eyes in the middle then does a correction movement
What in the vestibular system senses angular acceleration and head motion?
The semicircular canals
What in the vestibular system senses head position and gravity?
Saccule and utricle
What are the other inputs to the vestibular nuclei?
Cerebellum (primarily inhibitory)
Spinal cord
Pontine reticular formation
Contra-lateral vetibular nuclei
What is the difference between a head TILT and a head TURN?
Head tilt is one ear closer to the ground than the other
head turn is head parallel to the ground but nose turned to one side
What is a searching nystagmus?
What blind animals do, very uncoordinated
What is positional strabismus and why does it happen?
When the head is moved up or down the brain no longer tells the eye that it is moving up or down so eye does not correct
Where do the sympathetic fibres exit the spine?
thoracolumbar region
Where do the parasympathetic fibes exit the spinal cord?
Craniosacral system
