ET And XT Flashcards
When should you never give a partial prescription
Any ET
-they need a full Rx to make sure there is no type of accommodative issue going on
You will give the full cyclo refraction to all _____
Esotropes
Nonrefractive accommodative ET
- due to high AC/A ratio
- ET greater at N than D
- always important to eval at D and N
- may be intermittent alternating at N
- moderation hyperopia to myopia is seen (similar to general population)
Treatment for non refractive accomodative ET
- treat underlying refractive error-full RX
- bifocals based on AC/A
- segment height must bisect the pupil (executive or flat top)
- repeat cyclo yearly for any changes
- surgery is contraindicated. May be weaned off add if there is improved alignment at N
Who should get a bifocal
Non refractive accommodative ET
Mixed accommodative ET
Surgery and non refractive accommodative ET
Contraindicated
How long will the kid be in a bifocal for non refractive accommodative ET
Stay in it for a very long time, usually always
-could be weaned off about 7 years later
Mixed accommodative ET
- combination of refractive accommodative and non refractive accommodative findings
- high hyperopia and high AC/A ratio
Management of mixed accommodative ET
Full hyperopic Rx
Bifocal (based on AC/A)
Surgery is contraindicated
Surgery and mixed accomodative ET
Contraindicated
How can you suspect mixed accommodative ET
Some type of ET at D and N
Partially accommodative ET
- accommodation contribute to, but does not account for the entire deviation
- there is a reduction in the angle, but there is residual ET after treatment.
- this may result after delayed treatemtn of trule accommodative ET
- constant, unilateral
- suppression, ARC common
Early onset non accommodative ET
- onset is after about 6 months of age to before age 2
- clinically similar to infantile ET, but the onset is later
- ET same at distance and near
- there is no accommodative element
- insignificant amount of hyperopia
Management of early onset non accommodative ET
- correct error, consider prisms or bifocal
- amblyopia treatment
- VT to improve ranges
- consider surgery
- consider near cuases (even if child appears healthy)
Early onset vs infantile non accommodative ET
Looks similar but onset is later
Acute acquired ET
- comitant
- sudden onset in 3-5 years old (or older)
- unilateral and constant moderate angle (20-30PD)
- refractive error similar to general population
- could be as a s result of illness, stress, aging
Management of acute acquired ET
Neuro evaluations ASAP
Correction
Prism or surgery since patient probably had BV before the ET-sensory adaptations can still occur in some
Amblyopia treatment, if needed
Other esodeviations
- sensory ET
- divergence insuffiency ET
- consecutive ET
- microtropia-ultra small ET
- decomensating ET- FV no longer able to maintain EP
Who is a good candidate for strab surgery
Acute acquired ET
Sensory ET
- as ET that develops due to vision loss in one eye
- pathology prevents symmetrical visual stimulation OU
- poor VA in affected eye
- constant unilateral deviation, about 10-45 PD, poor cosmesis
Things that can cause sensory ET
Congenital cataract Corneal scarring Optica atrophy Prolonged blur Retinal/mac disease Anisometropia amblyopia Ptosis PHPV
Managment of sensory ET
-need to eliminate pathology (if possible) especially during the critical peieord
-polycarbonate lenses
-treat secondary amblyopia
Surgery can be for any residual deviation (or basically for cosmesis)
Divergence insufficiency ET
A non accommodative esodeviation greater at D than N
- comitant
- onset in adutls
- decreases fusional divergence at distance
- diplopia complaints at distance
- HA
Refractive error similar to normal population
No sensory adaptations since ate onset
Which deviation would you send out the door to the ER right away
Divergence insufficiency ET
Managment of DI ET
- neuro referral asap
- rhrorough eval
- correct any refractive error
- BO for diplopia at D
- VT
- Botox
- surgery in some cases if MD decides, but deviation only at distance
Consecutive ET
- esodevaition after strab surgery
- patient could be asymptomatic
- amblyopia could develop
- magnitude varies
- unilateral or alternating
- spontaneous improvement could occur
- treat refractive error
- try BO or plus lenses
- repeat surgery for very large or symptomatic consecutive deviations
Constant XT
-commonly seen in older patients with a sensory XT pr patients with a longstanding XT that age decompensating (decomensating XP)
Surgery may be indicated
Some patients may appreciate the enlarged visual field
Examples
- infantile XT
- sensory XT
Infantile XT
- large, constant angle
- could alternate
- less common than infantile ET
- present before 6 months of age
- these children are very likely to have neuro issues or craniofacial disorders
Things seen in infantile XT
- poor abduction on version (full on duction)
- DVD and OIO common
Good developmental Hx is needed and consider a an euro consult
Treat refractive error
Treate ambvlyopia
Surgery is performed for these kids-early to promote some form of sensory cooperation, since prognosis for BV is poor
Sensory XT
- any condition that causes vision loss in one eye can lead to sensory XT
- not sure why XT is seen in some and ET inothers
- poor VA
- poor cosmesis
- constant and unilateral
- large angle
VA in sensory XT
- need to determine if VA can be improved since this may improve alignment with peripheral fusion
- if VA improved, surgery can be useful for better alignment
- if VA is not correctable, misalignment could occur again after surgery
Consecutive XT
- this is common post surgery-could occur after months or years of surgery
- before another surgery, need to consider the type and mount of precision surgery, any duction limitation/scarring or non comitancy
Atypical UHARC is likely in these cases
IXT types
DE XT
Basic XT
CI XT
Divergence excess XT
- in childhood
- XT larger at distance, and seen prominently when targetis at a distance
Basic XT
In adutls
XT same at D and N
Convergence insufficiency XT
- in adults
- XT larger at near
Intermittent XT
- Most common XT
- deviation is latent and then becomes manifest
- onset before 5
Manifests during visual inattention, fatugye or stress because compensating fusional factors are not active
Could occur late in the day, with fatugyem, when daydreaming, when drowsy
Bright light may cause reflex closure of one eye
IXT can be assocaited with
Small hyperopia and/or A/V pattern
Untreated intermittent XT
Can lead to constant
-it will start to manifest at lower levels of fatigue and occurs for longer
Bright light causing someone to close an eye
IXT
Sensory adaptation of IXT
May occur after some diplopia- then suppression or ARC
Stereo and NRC and IXT
Prestn if control is good
Amblyopia and IXT
Not common unless constant deviation was early in life
CI XT
- XT greater at N
- usually an intermittent alternating deviation at near
- low AC/A
- poor fusion convergence amplitudes and receded NPC
- VT is successful in these cases-pencil push ups, convergence based computer programs
- BI reading glasses could be used
