Download Strabismus

Strabismus
Department of Ophthalmology
Tianjin Medical University Hospital
Extrinsic muscles

Inferior rectus muscle
 Superior rectus muscle
 Medial rectus muscle
 Temporal rectus muscle
 Superior oblique muscle
 Inferior oblique muscle
Actions

Abduction
 Adduction
 Elevation
 Depression
 Extorsion
 Intorsion
Strabismus

Concept: The control of the centre is with
trouble, the force of extrinsic muscle isn’t in
balance, visual axes reveal in separated state,
one is gazing at the object, another is
deviated from the object.
 Concomitant and non-concomitant
(paralytic strabismus)
Strabismus---examinations
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History: time and age of onset, treatment, family
history
Inspection: deviating direction and degree of
ocular position
Visual acuity and refractive examination: near, far
vision, corrected vision, 1% atropine
Cover test: monocular cover test (alternating or
continual cover test), cover-uncover test
Examination of eye movement
Strabismus---examinations
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Determination of the angle of strabismus
Corneal reflection of light point: pupillary margin--the deviation is about 10-15°; between
pupillary margin and the corneal limbus---25-30°;
the corneal limbus---45°
Measure with strabismeter
Prism cover test
Maddox rod plus prism test
Examination of synoptophore
Concomitant esotropia

One eye deviates to nasal side
 Eye movements is basically normal, the
deviating angles are equal in any direction
of fixation
 The first deviating angle is equal to the
second one
 Without diplopia
Concomitant exotropia

The position of one eye is deviated to
temporal side
 Without disturbance of eye movement
 The first deviating angle is equal to the
second one
 Without diplopia
Paralytic strabismus

Restriction of eye movement
 Compensatory head position: in order to
avoid or alleviate the interference of
diplopia
 The second deviating angle is greater than
the first
 Diplopia
 Ocular vertigo and staggering gait
Differentiation between paralytic
and concomitant strabismus
Paralytic
Concomitant
Onset
sudden
Eye movement
Disturbance in active
direction of paretic muscle
Gradually
develop
normal
Deviating angle The 2nd deviating angle>the The same of
primary one
both
Diplopia
Exist
No
Compensatory
head position
Exist
No
Review

How many extrinsic muscles ?
 What are the actions of extrinsic muscles ?
 How to differentiate concomitant and
paralytic strabismus ?