7 - Strabismus Dr. O Flashcards
Consequenses of strab
Risk of amblyopia, reduced stereo and fusion, suppression, change of ARC
Symptoms: diplopia, blur, HA, anom head positionsing, asthenopia
Prevalence of strab
General pop 2-6%
Young children 2-3%
BEPEDS/MEPEDS:
Risk factors for ET
-122x’s more likely with __D spherical equivalent refractive error
-2x’s more likely with __D aniso
+5.00 or more D
1.00+ D
BEPEDS/MEPEDS: Risk factors for ET -pre-K kids have a ~\_\_x’s greater chance -maternal smoking during pregnancy -gestational age <33 weeks
8x’s
2x’s
4x’s
BEPEDS/MEPEDS: Risk factors for XT -6x’s more likely with \_\_D astigmatism -maternal smoking during pregnancy -gestational age <33 weeks -gender
2.50+ D
3x’s
2x’s
1.6x’s more likely if female
BEPEDS/MEPEDS:
Risk factors
-type of deviation assoc w/ family history, gender predilection, and variation by ethnic group
XT (females more likely)
Strabismus Neuromuscular abnormalities time of onset: -infantile -congenital -acquired
I = first 6 months
C = at birth
A = after 6 months
Strabismus
-types of acquired deviations (3)
Acute (trauma, infection, etc.)
Long-standing
Consecutive (sx over-correction)
Strabismus
-when to use prism
NRC only!
If already developed NRC and BV
Strabismus prognosis
- sensory adaptations (3)
- prognosis worse with (3)
Amblyopia, suppression, ARC
ET, ARC, constant unilateral strab
Strab: correction of refrative error
- fully correct (2)
- if no strabismus
Anisometropia, astigmatism
Cut by same amount OD, OS
Strab: added lenses
- when to use
- where to place bifocal in younger children
- how often to weat them
For add’l alignment and fusion with high AC/As
Bisect the pupil
FTW
Strab: added lenses
- added minus
- why
- do not over-minus (3)
Intermittent XT (IXT scale)
Accomm drive is incr = collapses the angle
CI, presbyopia, accomm problems
Strab: prism
- how much/range
- why keep w/in range
Up to 16-18pd
Greater than this needs sx
- deviation becomes visible
- glasses will weigh a lot
Strab: prism
- when to use Fresnel
- when to not use Fresnel and why
Acute strab pts
Larger amounts compromise VA (streaks)
Strab: botox
-why it’s not used a lot
Varying resopnses and improvement vs sx
Strab: referral for sx
- contraindicated
- watch __
Accommodative ETs
IXTs with good control (0-2 on the scale)
Strab: referral for sx
- make sure __ is tx
- infantile strab
- educate family on
Amblyopia - w/o clarity, the eye will continue to turn due to lack of stimulation
Earlier = better
Possible need for revisions
Strab: sx
-recession vs resection
Recession
- muscle is detached, reattached further back
- more pull (“stronger”)
- same length
Resection
- muscle is shortened, reattached to original site
- weakens it a bit
Strab: sx
- adjustable sutures
- why
Can be adjusted while in recovery
Afterwards, becomes permanent
Fine-tune, reduce re-operation rates
PseudoET
-when is it seen
Wide, flat nose bridge with prominent epicanthal folds, small PD
May actually have a deviation - over-diagnosis of pseudo!
Infantile ET
- onset
- type of deviation
- assoc condns
- many have __
Birth-6 months
Large constant (>30pd)
Other neurological/developmental condns
Cross fixation - use adducted eye to look into contralateral view
Strab type assoc with: A or V pattern DVD (diss vertical dev) OIO (over-action of IO) Latent nystagmus Anomalous head position
Infantile ET
Accommodative ET
- onset
- may be precipitated by
- amblyopia
- diplopia may be followed by
6mo - 7yrs
Intermittent -> constant
Trauma (accomm spasm)
With large constant unilateral angles
Active suppression
Management of refractive accommodative ET
- correction
- amblyopia tx
Full hyperopic
-residual ET may not respond to correction due to ARC/suppression
If VA doesn’t fully improve with rx
