Orthoptics Flashcards
What is the purpose of a cover test?
Detect a manifest squint
What is needed for a cover test?
Occluder
Pen torch
Near and distance fixation target
How is a cover test performed?
Corneal reflections - are they symmetrical
Cover one eye, watch the other eye for movement, if it moves to fix on the target this a a tropia
The direction of movement tells you which type
What will outward movement of the eye tell you?
Esotropia - the eye will have a squint inwards
What will inward movement of the eye tell you?
Exotropia - the eye will have a squint outwards
What will downward movement of the eye tell you?
Hypertropia - the eye has a quint upwards
What will upward movement of the eye tell you?
Hypotropia - the eye has a squint downwards
What will a normal ocular motility test show?
There should be no visible sclera left in either eye in each position of gaze
Visible sclera means there is a weak muscle
What muscles will be tested looking straight up?
SR/ IO
What muscles will be tested to look up and out?
Superior rectus
What muscles will be tested to look up and in?
Inferior oblique
What muscles will be tested to look to the left?
Lateral rectus (abducens)
What muscle will be tested to look down and out?
Inferior rectus
What muscles will be tested to look down and in?
Superior oblique (trochlear)
What muscles will be tested to look straight down?
Inferior rectus and superior oblique