Exotrpoia
With A Patterns
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If
exotropia is at least 20 prism diopter
more in down gaze ( 25 degree
down) than the up gaze (25 degree up)
then it called as A pattern exotropia.
Causes of A
-pattern strabismus
- Superior oblique
muscle over action
- Relative under
action of the Inferior oblique muscles
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Management Of A-Pattern
Strabismus |
Surgical treatment of
Exotropia with A -pattern
strabismus with Superior oblique
muscle overaction
-
Lateral rectus muscle
recessions with superior
oblique muscle weakening
-
Lateral rectus muscle
recession with Medial rectus
resection with superior
oblique muscle weakening
|
Surgical treatment of
Exotropia with A-pattern
strabismus without superior
oblique muscle overaction |
-
Bilateral lateral rectus muscle
recessions with down shift
-
Lateral rectus muscle recessions
with down shift + medial rectus
muscle resections with up shift
|
Bilateral
lateral rectus muscle recessions with down
shift |
Lateral
rectus muscle recessions with down shift +
medial rectus muscle resections with up
shift |
|
Surgical treatment of Esotropia with
A-pattern strabismus
with
superior oblique
muscle over action |
- Medial
rectus muscle recessions with
superior oblique muscle
weakening
- Medial
rectus muscle recession with
lateral rectus resection with
superior oblique muscle
weakening
|
Surgical treatment of Esotropia with
A-pattern strabismus
without oblique muscle overaction |
- Bilateral medial
rectus muscle recessions with up shift
- Medial
rectus muscle recessions with up shift +
lateral rectus muscle resections with
down shift
|
Bilateral medial rectus muscle recessions
with up shift
|
Medial
rectus muscle recessions with up shift +
lateral rectus muscle resections with down
shift |