A and V pattern and overaction of oblique.ppt
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Transcript of A and V pattern and overaction of oblique.ppt
Overaction of oblique muscles and A - V patterns
Department of pediatric ophthalmology - VNIO
Introduction
• Strabismus with overaction of oblique muscles are common.
• A and V patterns are changes of deviation when patient looks up or down.
• A pattern: increasing divergence in down gaze >10PD
• V pattern: increasing divergence in up gaze >15PD
Inferior oblique overaction
• Primary Inferior oblique overaction– The cause is unknown– Mostly are bilateral– Often associate with congenital esotropia, but
become manifest at 1-2 year of age– Head tilt test nagative– No under action of ipsilateral SO
• Secondary Inferior oblique overaction– Due to superior oblique palsy
Inferior oblique overaction
• Clinical features – Upshoot of adducting eye– Increasing deviation in up-gaze, always cause
V pattern– Bilateral IO overaction cause:
• right hypertropia in left gaze• left hypertropia in right gaze
Superior oblique overaction
• Etiology – Primary superior oblique overaction: The
cause is unknown– Secondary superior oblique overaction:Due to
paresis of contralateral inferior rectus or ipsilateral inferior oblique palsy
Inferior oblique overaction
• Management IO overaction– Weekening procedure:
IO overaction 2+ or more• IO Recession• IO Myectomy • IO Anteriorization
Superior oblique overaction
• Clinical features:– Down shoot of adducting eye on version– A pattern in down gaze– Bilateral SO overaction cause:
• right hypotropia in left gaze• left hypotropia in right gaze
Superior oblique overaction
• Management of SO overaction– SO weakening procedures
• Superior oblique tenotomy• Silicone tendon expander• Split tendon elongation• Posterior tenectomy
Management A,V pattern without obliques overaction
- V pattern
+Transpose MR downward
+ Transpose LR upward
- A pattern
+ Transpose MR up
+Transpose LR down
Thank you for your attention