Oculomotor disorders Flashcards
Strabismus?
Misalignment of the visual axes
Types of strabismus?
Paralytic (Non-comitant)
Non-paralytic (Comitant)
Characteristics of Paralytic Strabismus?
Adult Angle of deviation varies in different fields of gaze Diplopia No amblyopia Muscle weakness identified
Characteristics of comitant strabismus?
Early childhood Angle of deviation remains constant in different fields of gaze No diplopia Amblyopia No muscle weakness identified
Tropia?
Visible deviation always
ESOtropia?
Inward (“Crossed Eyes”)
EXOtropia?
Outward (“Wall Eyes”)
HYPERtropia?
Upward
HYPOtropia?
Downward
Phoria?
Aligned unless fusion is disrupted
Movements of only one eye?
Duction
ADduction?
Move in toward nose
ABduction?
Move out toward ear
SUPRAduction?
Elevation, move up
INFRAduction?
Depression, move down
Movement of both eyes?
Versions
Dextroversion?
Right gaze
Levoversion?
Left gaze
Supraversion?
Up gaze
Infraversion?
Down gaze
Vergence?
Movement of both eyes in opposite directions
Convergence?
Movement of both eyes toward nose (in)
Divergence?
Movement of both eyes away from nose (out)
Main use of divergence?
Not well developed except to return from converged position
Intorsion?
Rotation of 12 o’clock position of the cornea toward the nose
SO and SR
Extorsion?
Rotation of 12 o’clock position of the cornea away from the nose
IO and IR
Nystagmus?
To and from oscillations of eyes
Jerk Nystagmus?
Slow then fast recovery (neurologic)
Pendular nystagmus?
Equal amplitude to and fro (poor vision)
Diplopia?
Sees two images with both eyes open
What does diplopia indicate? Causes?
Acquired weakness of EOM
Palsy of CN III, IV, VI
Greatest deviation in a patient with diplopia is seen when?
Direction of action of weak muscle
Horizontal diplopia?
Weak LR or MR
Vertical diplopia?
Weak SO, IO, SR, IR
