Strab II - Management of Esotropia

what treatment can you offer a very young child with negative PAT in which you are not entirely sure regarding sensory fusion status?

as long as NC and have normal peripheral fusion, can prescribe corrective prism and titrate over time as passive VT - titrate 2-4 prims diopters at a time - monitor <D and sensory fusion

what are the 4 main etiological causes behind acute-onset comitant ET?

following occlusion chronic illness/emotional stress (Sometimes after viral illness or psychogenic) idiopathic (MC) neurological (Need to R/O brain tumor)

what is the best prognostic factor for ET? worst?

best: normal sensory fusion (higher level, better prognosis) Doesn't need to be in free space Can be in MA or with neutralizing prism As long as they can demonstrate SF, better prognosis worse: AC

for an intermittent ET, what should you do in phase 3

improve SM in free space: - expand fusional divergence ranges at near - improve vergence facility - proceed to intermediate and far distances consider prism and/or added lenses

what is phase 2 of treating ETs? what are its components?

improve monocular visual function (if not amblyopia, you can skip phase 2) - treat amblyopia if present - normalize accommodative function - reassess ET characteristics and sensory fusion status before proceeding

if there is residual ET after surgery, what should you recomend?

lenses, prism, VT

why is follow up crucial in a partially accommodative ET?

likely to develop - amblyopia - suppression - AC

which AC treatment options use full time occlusion?

overcorrecting prism sensory stimulation flom swing (sometimes)

what are the 3 types of accommodative ETs?

refractive: normal AC/A ET aka uncorrective hyperopia (+) lenses at distance non-refractive: high AC/A (+) lenses at near combination (+) lenses at distance w/ ADD at near

sensory esotropia is the second most common presenting sign of ______

retinoblastoma *should perform DFE at 1st visit for all tropias

why may a surgery on an infantile esotrope be unsucessful in correcting the entire magnitude of deviation?

unstable/inaccurate measures often taken in children so young (concerns about putting babies under gen anesthesia)

what is the prognosis for normal BV like in DI?

very good - b/c had normal BV for many years

what is the normal BV prognosis like for acute onset comitant ET?

very good (if no CNS pathology) If neuro consult negative and Rx'ed full plus and ET still present - Tx options: Prism, VT, surgery

accommodative esotropia (is/is not) primary care

yes! Partially Accommodative is secondary care

what 2 factors are critical in determining whether a constant ET can complete phase 5?

<D magnitude and compensating BI vergence range

Infantile Esotropia: Types?

- Early-onset accommodative ET (So easy to tx) - Sensory ET (Make sure no ocular disease ex. Retinoblastoma) - Other forms of ET

Infantile ET: Diagnosis?

- Onset < 6 months - Large (30-70Δ) relatively stable angle - Normal CNS - Rule out other forms of ET (Can't just diagnose based on onset!) - Rule out accommodative ET (can still have at 3-4mo old they have fairly good accommodation)

describe how the prism adaptation test is performed

- PACT for baseline <D - Rx prims resulting in ortho/small exo over fixing eye - patient wears prism in office for 30-45 min - PACT reevaluated: negative PAT = ortho/slight exo positive PAT = eso --> suggest AC

what are the 3 components of phase 3?

- eliminate AC - eliminate peripheral suppression - improve/stabilize peripheral sensory fusion and increase motor fusion

what are the advantages of simply aiming for increased fusional vergence ranges (instead of normal BV)?

- improve aesthenopic symptoms - improve cosmetic appearance: ET smaller under binocular viewing conditions and increase patient's control & thus cosmesis

what are the 6 major management options for those with ET?

- no tx *Monitor - lenses - prims - occlusion - VT - surgery Sometimes you use all of that for one patient and sometimes is one of one, one mode of treatment, one modality, and that's sufficient.

what are the 3 consistent characteristics of infantile ET?

- onset <6 months - large (30-70 diopters) relatively stable angle - normal CNS

describe the following success rate percentages according to Wick in acccommodative ETs - refractive (basic): intermittent ____%, constant ____% - nonrefractive (CE): intermittent ____%, constant ____%

- refractive (basic): intermittent 100%, constant 90% - nonrefractive (CE): intermittent 100%, constant 75%

what are some important patient ed points to make when describing glasses as a treatment for accommodative ET?

- warn about ET without glasses: glasses do not make ET go away - will glasses and can switch to CL/LASIK when older - tell parent child must look through bifocals *parents will think the glasses are making the ET worse b/c it was int before and now EVERY TIME they take the glasses off they have an ET b/c the pts got used to seeing single and clear w/ glasses on so if they remove glasses they'll accommodate as much as possible to see clearly. Educate parents about this! And ask them to watch carefully to see if any ET occurs w/ the glasses on!

what are 3 options for an ET that cannot accept full distance plus?

1 cut distance and give add (cut distance and give add to help relax accommodation -> monitor and try to increase plus at distance) 2 cyclotherapy 3 gradual change in Rx (specs or CLs) which option you go w/ depends on how much plus your pt can accept

what 2 tests can be done to test correspondence in someone with a smaller angle strabismus?

1. Cuppers bifoveal 2. HBAIT

in a 6th nerve palsy and Duane's syndrome, the esodeviation is larger with 1. 2.

1. affected eye fixating 2. affected field of gaze

what are the 5 components that make up Flom's functional cure?

1. clear comfortable single BV at all distances in all gazes up a normal NPC 2. occasional turning (1%) with diplopia 3. allow prism in SRx up to 5 diopters 4. normal motor fusion ranges 5. stereopsis

what does eliminating AC improve prognosis for?

1. normal BV 2. increased stability of post-surgical eye alignment

what if a CET cannot establish NBV at orthoposition in free space?

1. rx prism/added lenses 2. refer for strab surgery

what are 4 factors that make a patient the best surgical candidate for ET? f/u?

1. wearing max hyperopic correction 2. no to minimal amblyopia (amblyopia does not mean you can't get get surgery, but more likely to drift again post-op b/c of disparity between 2 eyes) 3. normal SF (phases 3+4) 4. good motor fusion around <D (phases 3+4) Post‐surgical follow‐up? f/u - pts can't always see if they have a small amount of residual ET -> could do prism or VT to treat residual deviation

what are the management options for someone with DRS if they 1. have a head turn or ET in primary gaze Ex. Neck issues, weird head turn 2. do NOT have a head turn or ET in primary gaze

1. yes head turn/ET in primary - refer to peds OD for: PRISM(relieving or yoked) , VT, SURGERY (rare) 2. no head turn/ET in primary - no treatment; reassure patient

____-____% of those with pseudoesotropia are later diagnosed with esotropia what is the best management option for those with pseudoesotropia?

10-19% later diagnosed with esotropia They missed it or they developed it later (bring pt back in a couple months just in case) serial examinations and parent education

when does infantile esotropia typically develop?

2-4 months of age

what are the expected VA ranges in those with sensory ET?

20/60 - LP Usually more like 20/200-20/600 and blind eye will drift Amblyopia may be superimposed develop amblyopia on top of sensory ET Ex. Cataract -> eye turns -> amblyopia

what should the follow up schedule for a pseudoesotrope be?

3-4 months because many later develop esotropia

accommodative ET is usually diagnosed between ____ mo. and _____ years

4 mo to 7 years

when should you follow up after a new Rx has been dispensed to treat ET? what tests should you run at the follow up?

4-6 weeks evaluate sensory fusion Cover test Over-refraction and VA lean towards seeing them sooner b/c if it's not working then you can make changes

according to Wick & Cook, CETs with AC had a _____% Flom functional cure and ____% almost cure provided sufficient time of up to ____ months was devoted to VT

42% functional cure 53% almost cure up to 12 months AC is worst prognosis factor but it doesn't mean you cant tx these patients

accommodation in young children is mature by ____ months of age. what is the significance of this?

6 months of age - accommodative response matures quickly and very young infants are capable of accommodating --> leading to accommodative ET if have high hyperopic refraction

when a patient is suspected of having divergence insufficiency, one should rule out ____

6th nerve palsy Consider neurological evaluations when sudden onset and no apparent cause; acute-onset comitant ET? Ex. Always had high EP and then ET -> decompensation New ET w/o Hx -> send for work up

describe where the bifocal should be placed for the following ages: <5 6-7 >=8-9

<5 = mid-pupil 6-7 = lower pupil margin >=8-9 = lower lid margin or PAL

describe where the PAL should be placed for the following ages: <7 >= 8

<7 = 4mm above mid pupil >= 8 = 2mm above mid pupil

for CET, it is important to eliminate suppression and establish normal SF at _____

<D

full time occlusion is typically used to tx (AC/suppression)

AC

Esotropia Classification: Based on AC/A? CE basic eso DI

AC/A is a big driver for deciding type of tx

ET Classification: Based on Accommodative Etiology?

Accommodative Partially Accommodative ET Non-accommodative ET

Fundamental Principles of Treatment for Esotropia?

All ET's are not the same Treatment is based on: • Type of ET • Diagnostic profile including sensory fusion status ex. freq, correspondence • Treatment options available • Desired outcome (Stereo, straight head position, aesthetic, etc. (what's the goal?))

Follow up treat ET: Cover test

Cover test - if residual ET, re-evaluate fusion with prism if prism allows pt to have fusion, this is appropriate time to add prism if it wasn't done during initial visit

what type of bifocal should you begin within in an ET child that needs an add?

FT-28

what is phase 1 of treating ET?

Establish initial optical Rx Rx optimum lenses that: - correct RE - maximally reduce size of ET (D+N) • Distance SRx - push plus (age dependent) • Consider plus add for near • Consider prism IF normal SF

which AC treatment is safe to do for those who are unsure they can finish the entire treatment? why?

Flom swing - starting at <S and diverging magnitude of <D - if unable to diverge magnitude of <D, OK because will just revert to AC and not have diplopia (Start at <S and just train divergence NOT BREAKING DOWN SYSTEM)

what are some neurological signs/symptoms that DEFINITELY warrant referral?

HA ONH edema clumsiness, ataxia nystagmus, APD nausea/vomiting enlarged head size

what is the amount of relieving prism to prescribe for an ET?

Horizontal relieving prism only if BV can be established/stabilized in free space smallest magnitude to achieve fusion - for 6-20 prism diopter ET, leave residual vergence demand of 4-6 prism diopters

If NC & suppression, how do we eliminate peripheral suppression?

If NC & suppression, eliminate peripheral suppression • Target placement is critical (<D) • Target content also important: large w/ low detail if pt still suppressing -> modify coaching, flicker target, blink eyes, adjust contrast, etc. - Encourage pathological diplopia awareness (want to do anti-suppression therapy when eye is turned to encourage diplopia awareness -> want pt to know when their eye is turned out, should see double when eye is turned) -When have normal peripheral sensory fusion, improve motor fusion ranges around <D

Esotropia Classification: Based on Time of Onset?

Infantile ET • Onset <6 months • Classically considered non-accommodative (very difficult to get normal binocular vision in those patients versus somebody who's had normal binocular vision for a certain period of time) Acquired ET • Onset >6 months

what are some conditions that may cause sensory esotropia?

MC congenital/traumatic cataracts corneal opacities ONH or retinal lesions macular disease Not as common uncorrected aniso Ex. Plano, -14DS Moderate to profound vision in 1 eye -> tropia b/c difference in retinal clarity is obstruction to fusion

Magnitude in those with sensory ET?

Magnitude of ET varies

those with DI tend to have (NC/AC)

NC - lack of sensory adaptations with diplopia

what are some variable characteristics of infantile ET?

OIO >=72% (>1 year) DVD 50-75% (>2-3 years) A or V pattern latent nystagmus amblyopia 35-72% apparently defective abduction crossed fixation

what findings on CT and overrefraction would prompt you to do another cyclo on an ET?

OR: see more plus CT: see bigger ET than before

Order of tests at follow up to tx ET?

Order of tests to do at f/u: • intermittent ET - if you start w/ VA and CT, you are dissociated the pt a lot, so now they will deviate eyes more • IET - greater chance of getting stereo and normal sensory fusion response if you do test stereo/W4D prior to doing testing that would dissociate them a lot • stereo -> W4D -> CT -> VA and OR

Follow up treat ET: Over-refraction and VA

Over-refraction and VA - may need to repeated cyclo refraction - treat amblyopia if needed - if not amblyopic: test correspondence and in instrument sensory fusion if indicated may need to repeat cyclo if on OR you are seeing more plus -> maybe didn't pull out all hyperopia out of pt in initial visit

the prognosis for infantile esotropia is (good/poor) for normal BV/Flom cure

Poor prognosis b/c don't know if ever had normal fusion reasonable for cosmetic alignment and peripheral fusion Usually involves surgery

What are other ways to reassess esotropia prognsis?

Sensory fusion status?! NC? 2˚ fusion? 3˚ fusion? Other factors - Age of onset / duration - Frequency - Magnitude?? (magnitude doesn't matter for surgery but does matter if prescribing prism or doing VT) - Age of patient?? - Others.......

what type of ET should you especially want to rule out before diagnosing a child with infantile ET?

accommodative ET! e.g. 12 m/o with +5.00D hyperopia will have an ET due to large accommodative demand *Colin's notes: threshold of >=+1.25D where you would want to prescribe glasses for an infant to help with ET

what are 4 treatment options for partially accommodative ETs?

add prism (if normal SF) VT surgery (larger angle)

when should SMF and correspondence be assessed?

after optical correction and amblyopia treatment

what 3 factors should not be present in a patient with acute-onset comitant ET?

amblyopia, suppression, AC if truly recent, won't have had time to develop these

what are some neurological non localizing lesions that may cause acute-onset comitant ET?

cerebellar astrocytoma cerebellar medulloblastoma pontine glioma pseudotumor posterior fossa pilocytic astrocytoma nasopharyngeal angiofibroma

DI leads to a (comitant/non-comitant) ET and reduced (positive/negative) fusional vergence amplitudes

comitant ET reduced negative fusional vergence amplitudes

from the CEOS study (Strab 1), what magnitude of esotropia and hyperopia was found in children who did not have spontaneous resolution of their infantile esotropia?

constant ET >=40pd after 10 weeks on 2 xams and <=3.00D hyperopia

what type of deviation is considered an infantile estropia?

constant non accommodative larger angle ET in neurologically intact child that develops by 6 months of age NOT BORN WITH

a surgical treatment of sensory ET is usually primarily for ______ purposes

cosmetic Ex. 30ET w/ 20/80 due to sensory ET -> peds OD (ex try to get peripheral sensory fusion) -> surgical consult to at least make eyes look straight (eyes may just drift again b/c of reduced vision)

Example of pt who looks like they have bad sensory vision but sensory vision is fine?

could have someone who looks like they have bad sensory fusion -> possible that their sensory fusion is fine and they are just having a hard time diverging and that is why they are suppressing • give them neutralizing prism • W4D see 4 lights and no movement = normal sensory fusion • can make adjustments to the prism to see the amount they need to get normal sensory fusion

what is the prognosis like for a partially accommodative ET

depends on cosmetic vs. normal BV goal (secondary care)

what is phase 3 of treating ETs?

develop normal peripheral SMF

in general, why is it better for a child with infantile esotropia to receive surgery early? how early is considered too early for most surgeons? why?

earlier: better chance for stereo advocates of <12 months don't advocate <6 months; worried about neurological effects of general anesthesia

what is phase 4 of treating ETs?

eliminate central suppression establish normal central SMF at <D

what is the next step in phase 2 if your patient has CET and has NC?

eliminate peripheral suppression - encourage diplopia awareness - when have normal peripheral sensory fusion, improve motor fusion ranges around <D

what is partially accommodative esotropia?

esotropia with accommodative component but residual ET following full correction of ametropia

Follow up treat ET: evaluate sensory fusion

evaluate sensory fusion - STEREO (RDS) - second degree fusion (W4D/Peds Flashlight) (a lot of pts w/ ET, even w/ tx, can't appreciate stereo -> for these pts, evaluate 2nd degree sensory fusion)

what is phase 5 of treating ETs?

extend normal SMF to free space

true or false: comitancy is enough to rule out neurological disease in an ET

false Need Ocular motility examination

true or false: in CN 6 paresis management, one should: 1. refer for neuro consult 2. check for signs of child abuse 3. refer for immediate surgery

false - should postpone surgery by at least 6 months: may resolve especially if control disease such as HTN and DM - refer to peds OD in meantime for prism, VT or occlusion esp. monoc abduction Ex. CN6 palsy so you don't want MR contraction -> abduction to exercise MR (stretch it out) true • Neuro consult • If suspect head trauma - check for signs of child abuse

true or false: surgery on ETs can be performed while amblyopia treatment is still occurring

false! must resolve amblyopia before surgery

true or false: acute onset comitant ET is moderate to large angle of ET at distance only

false: moderate to large angle of ET at distance and near

true or false: usually infantile esotropes require one surgery for successful alignment

false: require multiple surgeries

in accommodative esotropes, one should consider Rx'ing full ______ and _____ at near

full cyclo add at near (if high AC/A) Don't always rx full cyclo but try to start with high RX and can always back off later Typically full cyclo if pt has constant ET

what is the prognosis like for normal BV in sensory ETs?

guarded with some exceptions e.g. toxoplasmosis scar on macula --> will never get normal BV

why does DI ET occur in older patinets?

have reduced compensating vergences with increasing age

when is accommodative esotropia prognosis EXCELLENT (2 factors)?

intermittent and/or short duration Dr. C's impression: many kids start off as intermittent accommodative ET but b/c they're left untreated, they become constant + AC or suppression

what is phase 1 of treating ET w/ cycloplegic refraction?

look at cycloplegic refraction data manipulate rx so that you can maximally reduce the size of the ET at both distance and near • more plus we can push = more likely to reduce ET rx an add - for pts w/ high AC/A ratio (convergence excess)

what are the 3 tests for larger angle ET correspondence? what can be performed if the 3 tests are unable to be performed? What if patient has fusion response?

major amblyoscope HBAIT Red lens/worth dot prism adaptation test if unable to do AC testing (e.g. if they adapt, this indirectly tells yo that they don't have good sensory fusion) W4D - perform UCT if pt gives fusion response to evaluate correspondence

when is a tropia considered a microtropia vs. larger angle tropia?

microtropia <10 larger tropia >10

what is an additional treatment to consider in CN 6 palsies so that there is not secondary contraction?

monocular occlusion: get paretic eye to abduct

after you verify refraction carefully in a partially accommodative esotrope, you should rx (more/less) plus if it is found

more plus After rx plus lenses and they still have residual strab They could not be a fully accommodative ET OR maybe you didn't give them full plus (scope over dry and if suspect cycloplege again)

why should you not eliminate AC or suppression unless you are sure the patient can complete the treatment program?

must be able to establish fusion with prism, VT, surgery - patient/parent must be ok with this (therapy intensive, make sure parents understand they can follow through, talk about possibility of needing treatment down the way) - potential for surgery always - otherwise patient will be left DIPLOPIC

is a neuro consult required in someone with DRS?

no

divergence insufficiency is an (accommodative/non-accommodative) ET that can develop suddenly

non-accommodative Intermittent or constant ET at distance but not at near (can be int at near) Larger ET at distance and often worse frequency

when is full time occlusion contraindicated for non-amblyopia treatment?

normal fusion somewhere e.g. if normal fusion at distance, can occlude at near only

what must a patient have to be prescribed prism?

normal sensory fusion - e.g. only if BV can be established/stabilized in free space

what is the best way to determine the amount of add for a child who is not cyclopleged? one who is?

not cyclopleged - calculated AC/A ratio - CT at near over trial frame cyclopleged - can give +3.00D if young child and hope for the best

in acute onset comitant ET, the ET (is/is not) related to RE and the patient has a (high/low/normal) AC/A Signs?

not related to RE normal AC/A Diplopia likely, but most not report, but may close / wink an eye

what are the treatment options for DI once a patient has been Rx'ed full plus and ET is still present?

prism VT surgery occlusion Normally do well w/ prism -> unsuccessful then surgery

what is phase 1 of treating ET w/ prism?

prism only IF: • pt has normal sensory fusion OR • can establish normal sensory fusion w/ prism

describe some common types of ET

pseudo infantile accommodative partially accommodative non-accommodative non-accommodative acute onset comitant ET sensory DI cyclic micro ET/monofixation syndrome paretic or mechanically restrictive: Duane's, 6th nerve palsy

what is the potential issue with full time occlusion for non-amblyopia tx?

reverse amblyopia in a child still in sensitive period prevent by alternating patching Ex. Patch amblyopic eye more often Even for adult patients out of sensitive period, should still do alternate patching

what is a potential solution to occluding an individual with normal sensory fusion at distance?

sector occlusion with LP bangerter foil can occlude at fixation distance where not fused or certain field of gaze

what is the most important factor in prognostic factors for esotropia?

sensory fusion status

what are the 3 methods to eliminate AC in CETs?

sensory stimulation at <D: ET >= 15-20 motor stimulation (Flom swing): ET <15-20 overcorrecting prism therapy: any size ET active therapy (sensory and motor) - wouldn't work very well for pts who are very young (around <6 y.o)

what 4 factors can classification of an ET be based on?

size of angle - Distance vs. near: AC/A ratio - Microtropia or not age of onset accommodative etiology AC/A No classification scheme works well for all ET's

the first management option in treating accommodative ETs is (surgery/spectacles)

spectacles! • Hyperopia +/or high AC/A • Response to lenses**** • Follow-up is imperative for definitive diagnosis Diagnosis is only certain after testing through cyclo + lenses don't do surgery in accommodative ETs

what is the best management for those with infantile esotropia?

surgery! - refer to Peds OD prior to surgeon

6th Nerve Palsy & Duane's Syndrome?

• Abduction deficit • ET primary gaze? • May have face turn toward affected eye • Differentiate whether 6th nerve palsy vs. Duane's type 1

what 3 components of an ocular exam is highly recommended in pseudoesotropes?

• Cycloplegic is standard of care • Rule out other forms of bonafide ET • Eye alignment & random dot stereopsis testing (Even if they have RDS, doesn't mean that they don't have an intermittent) • Serial examinations & parent education recommended

Infantile Esotropia Management?

• Make sure ruled-out accommET • Management is not primary eye care • Definite surgical candidate -Suggest refer to Peds OD prior to a surgeon.... • Prism prior to surgery (good precursor for surgery * esp some peripheral fusion before hand would be better) -Surgery - timing?

Management: Sensory ET?

• Take care of any active pathology • Consult w/ Peds-OD before strabismus surgeon - Although not best surgical candidates, some benefit cosmetically