Strabismus

Question 1

Orthophoria

Answer 1

the ideal condition of ocular

alignment under binocular conditions

Question 2

Heterophoria

Answer 2

ocular deviation kept latent by the fusional

mechanism (latent strabismus)

Question 3

Heterotropia

Answer 3

deviation that is manifest and not kept under control by
the fusional mechanism (manifest
strabismus)

Question 4

Eso-

Answer 4

this is also known as

convergent strabismus.

Question 5

Exo-

Answer 5

this is also known as

divergent strabismus.

Question 6

Hyper-

Answer 6

This is also known as

vertical strabismus.

Question 7

Hypo-

Answer 7

This is also known as

vertical strabismus

Question 8

-phoria

Answer 8

A latent deviation (e.g.,
esophoria, exophoria, right
hyperphoria) that is controlled
by the fusional mechanism so that
The eyes remain aligned under
normal binocular vision

Question 9

-tropia

Answer 9

A manifest deviation (eg,
esotropia, exotropia, right
hypertropia, excyclotropia) that
exceeds the control of the fusional
mechanism so that the eyes are not
aligned under binocular conditions
Can be intermittent or constant

Question 10

Comitant : (concomitant)

Answer 10

The
size of the deviation does not
vary by more than a few prism
diopters with direction of gaze
or with the eye used for fixating.

Question 11

Incomitant : (noncomitant)

Answer 11

The
deviation varies in size with the
direction of gaze or with the
eye used for fixating. Most
incomitant strabismus is
paralytic or restrictive.

Question 12

Alternating fixation

Answer 12

Spontaneous alternation of fixation from one eye to the other.

Question 13

Monocular fixation

Answer 13

Definite preference for fixation with one eye.

Question 14

Congenital

Answer 14

before 6 months / infantile. Antonym: acquired

Question 15

Torsional deviation

Answer 15

Incyclodeviation or Excyclodeviation

Question 16

rectus muscles

Answer 16

four of them: superior, inferior (CN VI), lateral, medial. All others (CN III innervation)

Question 17

oblique muscles

Answer 17

two of them: superior (CN IV) and inferior (CN III).

Question 18

Levator palpebrae superioris

Answer 18

LPS - innervated by CN III - elevates and retracts the upper eyelid

Question 19

primary position

Answer 19

the normal state of the eyes. The primary action of the muscle is the way the eye turns when it is contracted, away from the primary position. Eye can turn up to 50 degrees in any direction, but typically more than 15-20 degrees will result in head movement

Question 20

MR vs LR

Answer 20

medial rectus vs lateral rectus. Medial is an adductor, lateral is an abductor. The MR muscle is the only
rectus muscle that does not
have an oblique muscle running
tangential to it

Question 21

annulus of Zinn

Answer 21

ring of fibrous tissue surrounding the optic nerve at its entrance at the apex of the orbit. Origin of five of seven EOM

Question 22

limbus

Answer 22

border of iris and sclera

Question 23

Tenon’s capsule

Answer 23

membrane that envelopes the eyeball from the limbus to the optic nerve, separating it from the orbital fat and the socket which it moves

Question 24

retinoscopy

Answer 24

https://www.youtube.com/watch?v=kAreDffuVCQ

Question 25

epicanthic fold

Answer 25

denoting a fold of skin from the upper eyelid covering the inner angle of the eye, typical in many peoples of eastern Asia and found as a congenital abnormality elsewhere.