Dizziness, Vertigo, & Syncope Flashcards
Causes of “dizziness”?
Presyncope Loss of balance, unsteadiness of gait Vertigo Double Vision Psychological dissociative feelings Vague sensations
Causes of presyncope?
Orthostatic hypotension Cardiac Problems (Decreased cardiac output)
Gait imbalance in elderly –> neuronal loss due to aging or disease in networks the sub serve?
Cerebellar function Vestibular function Visual orientation Peripheral nerve function Motor strength Frontal lobe apraxia Basal ganglia Arthritis and Pain Inactivity and fear of falls
“True” Vertigo?
Disease of the vestibular system (central and peripheral)
Illusion of movement (whirling, spinning, swaying)
Nystagmus
Often accompanied by nausea and vertigo
How many degrees of freedom?
6
Roll?
Rotation around x axis
Yaw?
Rotation around z axis
Pitch?
Rotation around y axis
Translational motion?
Linear along x,y, and z
Rotational motion?
Angular around x, y, and z
What senses linear motion and effects of gravity?
Sacculus
Utricle
What does the sacculus lie coplanar to?
Vertical axis
What does the utricle lie coplanar to?
Horizontal axis
What detects angular movements?
Semicircular canals
What lies inside the semicircular canals? What do they do?
Ampulla –> detects rotational acceleration or deceleration within the plane of the canal
