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7/28/2019 Strabismus and Eye Muscle Surgery
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Strabismus
and Eye Muscle Surgery
G. Vike Vicente M.D.
Eye Doctors of Washington
G.Vicente,MD
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• Dr. Vicente Strabismus review outline:
• Horizontal strabismus – Anatomy review
– Nomenclature review
– Accommodative esotropia
• Pediatric Bifocals? – Infantile esotropia
– Viral & Diabetic esotropia
– Sensory strabismus
– Pseudostrabismus
– Duane’s syndrome
– Exotropia – Convergence insufficiency
– Phorias
– Tropias
– Eye Muscle Surgery• Recession
• Resection• Vertical Strabismus
– Parks’ Three step test
– Superior Oblique Palsy
– Brown Syndrome
– Inferior Oblique Overaction
– DVD- Dissociated Vertical Deviation – Blow out Fracture
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SkinConjunctiva
Tenon’s layer
Eye Muscles
Left eye
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Eye MusclesLeft eye
Superior Oblique/Trochlear Muscle
Superior Rectus Muscle
Lateral Rectus Muscle
Inferior Rectus Muscle
Inferior Oblique Muscle
Medial Rectus Muscle
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Nomenclature
• Orthorphoria o
• Esophoria E
• Esotropia ET
• Intermittent Esotropia E(T)
• Exophoria X
• Exotropia XT
• Intermittent Exotropia X(T)
• At near X(T)’
• Right Hypertropia RHT
convergent
divergent
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Strabismus Why is it Important?
• Preserving Stereo acuity 8 yo withworsening X(T) Intermittent Exotropia.
•Enlarging Visual field
– for Pts with ET.
• Appearance
– Would you hire me?
– Would you date me?
– Is there something wrong with you?...
•Diplopia
G.Vicente,MD
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Strabismus Why operate?
Diplopia
Can be a very debilitating symptom affecting lifestyle and
quality of life.G.Vicente,MD
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Accommodative esotropia
Typically presents around age 2 years, may presentacutely.
Always put +3.00 sph OU when you see an ET for the
first time. If its improved or resolved think Accom ET!
Why is there ET with Accommodation?
Eyes will usually converge when accommodation is
attempted. If high hyperope then must accommodate, if
accommodating then will converge, cross, specially atnear.
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Accommodative ET Use cyclogyl to measure Rx (wait 40 minutes) Recheck 4 weeks later with glasses, If still some ET present, use Atropine to make
sure you measured the full CRx
Tell parents they eyes will continue to crossevery time the glasses come off.
Always give full CRx, cycloplegic refraction forsuspected Accom ET.
Child might not like full CRx Use Atropine when using hyperopic glasses for
the first time, it will break the accommodativespasm and allow the pt to get used to the
glasses.
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emmetropia
+3D
CRx = +5D hyperopia, no accommodation
+5D hyperopia
(lets say the pt is able to accommodate 3D,
so effectively they are only +2D hyperope)
+3D
+5D +3D
+5D Rx +3D accom spasm = +8D, pt is only a +5.00 so
Pt ends up feeling like a -3.00D myope with your Rx
My son does not like the glasses you recommended,
The optician was right, they are too strong
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Accommodative ET, AC/A
AC/A =
Accommodative convergence / accommodation
An accom ET crosses because he/she has normal AC/A.
Ie of high AC/A: an emmetrope, WRx = plano OU pt
At Distance they are ortho
At near they are 25PD ET’
They are over converging for a normal amount of accommodation.
This is a high AC/A ratio.
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AC/A
Example of a pt with low AC/A?
who underconverges?
+8.00 hyperope who is ortho at near anddistance.
They have adapted to their hyperopia byunder converging.
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Infantile Esotropia Syndrome
Aka congenital esotropia
Esotropia usually present by age 6months
Not improved with hyperopic Rx Most pts will never have good stereo
Associated with inferior oblique overaction
And DVD, dissociated verticaldeviation.
The 2 latter conditions may not bepresent initially must remember towarn parents that if they occur in thefuture it is not the surgeon’s fault.
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Infantile esotropia continued
Must rule out other causes
CN 6 palsy from birth? Often spontaneous
resolution
Remember some variable, intermittentstrabismus is expected until 4 months of
age.
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Esotropia associated with Viral
illness Often self limited, will spontaneously
resolve in 3-6 months.
Acute
Not improved with hyperopic glasses.
Consider ruling out neoplastic causes.
Treat/prevent amblyopia in the mean time
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Esotropia associated with Diabetes
Abducens, lateral, CN 6 usually affected.
Isolated unilateral palsy
Ischemic
Usually resolves after 4-6 months.
Consider Botox in the meantime, to whichmuscle…
The medial rectus
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Botox injection to Medial Rectus
For temporary lateral rectus ischemic palsy
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Add droopy lid
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Sensory strabismus - Peds
Young pts with poor monocular vision willoften develop esotropia in that eye.
OKAP NOTE:::::::: DOES YOUR PEDS PT HAVE ESOTROPIA
BECAUSE THEY CAN NOT SEE OUT OFTHAT EYE?
WHY? CATARARCT, RETINOBLASTOMA,MACULAR SCAR, ANISOMETROPIA?
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Duane’s Syndrome
G. Vike Vicente, MD
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Duane’s Syndrome ALL FORMS RETRACT IN ADDUCTION
• Abda Dubba Deux• Type I: deficit in abduction and retraction in adduction
(due to co-contraction of MR and LR
• Type II: deficit in adduction
• Type III: both.
• Watch for strabismus, face turn: attitude
• Usually sporadic, also think Goldenhars, Wildervancksyndromes
• OS more common than OD• Females > males
• Watch also for vertical pull, leashing phenomenom.
• Occasional absent CN 6 nucleus.
G.Vicente
Duane’s Syndrome Type I: OS
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Duane s Syndrome Type I: OS
limited abduction,
retraction in adduction
G.Vicente
Duane’s Syndrome Type I
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Duane s Syndrome Type I
limited abduction,
retraction in adduction: superior view
notice co-contraction of LMR & LLR
Dr. G.Vicente
OS OD
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Duane’s Syndrome Type I
retraction in adduction limited abduction, superior view
OS OD
G.Vicente
Duane’s Syndrome Type II: OS
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Duane s Syndrome Type II: OS
limited adduction
retraction in adduction
G.Vicente
Duane’s Syndrome Type III: OS
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Duane s Syndrome Type III: OS
limited adduction and abduction
retraction in adduction
G.Vicente
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Funny Story…
• 15 yo wm
• Bad attitude…
• ortho…? Right gaze,
Left face turn…
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Funny Story…
• 15 yo wm
• Bad attitude…
• ortho…?
• 30 PD LET actually,
• But can fuse in rightgaze, left head turn
And I forgot to
Check his ductions…
1ry gaze
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Funny Story…
• 15 yo wm
• Bad attitude…
• ortho…?
• 30 PD LET actually,
• But can fuse in rightgaze, left head turn
• And, I forgot to notice
the limited abduction
and narrow fissure inadduction
Left gaze,
Right face turn…
Duane’s Syndrome Type I: OS
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Duane s Syndrome Type I: OS
limited abduction,
retraction in adduction
G.Vicente
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Duane’s treatment
• If strabismus in 1ry position
– ET>XT
• Or significant head turn: attitude.
• Never resect LR if no abduction.
– This will worsen globe retraction and not
improve abduction.
G.Vicente
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Sensory strabismus- adults Adult with poor monocular
vision will often developexotropia. Think dense cataract X 5
years Warn pt about possible post
op diplopia and need forstrabismus surgery
Pt may have lost the ability tofuse.
Think monovision, orunilateral under correctionLasik pt who had undiagnosed
intermittent exotropia.
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Pseudo ET
Orthophoria
Esotropia
G.Vicente,MD
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Initially the baby has
a “button nose, with
a very flat nasal
bridge.The baby lids cover
the medial white part
of the eyes causing
the appearance of
the eyes being
crossed. As the nasal bridge
develops and grows
forward it will drag
the medial portion of
the lids inward
reducing theappearance of the
eyes being crossed.
1
Pseudo ET
G.Vicente,MD
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Initially the baby has
a “button nose, with
a very flat nasal
bridge.The baby lids cover
the medial white part
of the eyes causing
the appearance of
the eyes being
crossed. As the nasal bridge
develops and grows
forward it will drag
the medial portion of
the lids inward
reducing theappearance of the
eyes being crossed.
2
Pseudo ET
G.Vicente,MD
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Initially the baby has
a “button nose, with
a very flat nasal
bridge.The baby lids cover
the medial white part
of the eyes causing
the appearance of
the eyes being
crossed. As the nasal bridge
develops and grows
forward it will drag
the medial portion of
the lids inward
reducing theappearance of the
eyes being crossed.
3
Pseudo ET
G.Vicente,MD
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Initially the baby has
a “button nose, with
a very flat nasal
bridge.The baby lids cover
the medial white part
of the eyes causing
the appearance of
the eyes being
crossed. As the nasal bridge
develops and grows
forward it will drag
the medial portion of
the lids inward
reducing theappearance of the
eyes being crossed.
4
Pseudo ET
G.Vicente,MD
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Exotropia
Intermittent is very common
How symptomatic are they?
Make sure they have BCVA glasses
Diplopia?
Often familial, so what? Dad had it too.
“What hump?”
Intermittent exotropia can breakdown over time,check serial stereo. If worsening think surgery.
Most common time of pediatric surgery is 7 years old.
Can the pt converge?
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Convergence insufficiency
Seen in kids who have trouble reading Adults with Parkinson’s disease Sometimes over diagnosed by some vision
therapy developmental optometrist. Consider
Convergence exercises by an orthoptist, or software Decreasing add in bifocals to extend reading distance
(holding reading material further away) Prisms, etc. pencil pushups.
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Nomenclature
• Orthorphoria o
• Esophoria E
• Esotropia ET
• Intermittent Esotropia E(T)
• Exophoria X
• Exotropia XT
• Intermittent Exotropia X(T)
• At near X(T)’
• Right Hypertropia RHT
convergent
divergent
G.Vicente,MD
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Cover – Uncover test
Orthophoria, normal
No complaints, asymptomatic
G.Vicente,MD
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Cover – Uncover test
Esophoria, abnormal, common
Only seen when eye is covered
Often asymptomatic, no complaints
Note OS does not move.
G.Vicente,MD
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Cover – Uncover test
Exophoria, abnormal, common
Only seen when eye is covered
Note OS does not move
Often asymptomatic, no complaints.
G.Vicente,MD
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Alternate cover test
• Remember to allow the pt time to fixate on
the target, give them a minute.
• Then quickly cover the other eye to
prevent the pt from regaining fusion.
• But do not go back and forth quickly
because the pt will not have time to
refixate.
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Alternate Cover test
Exotropia, intermittent
May be visible with or without
alternate cover May have intermittent diplopia,
especially when tired or sick
Mom sees misalignment every
now and then.
G.Vicente,MD
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Alternate Cover test
Exotropia, Constant
May be visible with or without
alternate cover
May or may not have constant
diplopiaG.Vicente,MD
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Cover Uncover test
Left Exotropia, Constant
May be visible with or without
alternate cover
Right eye preference
G.Vicente,MD
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Cover Uncover test
Left Exotropia, Constant
May be visible with or without
alternate cover
Right eye preference
Note: no eye movement, so besure to check both sides G.Vicente,MD
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Normal Convergence
Convergence Insufficiency
G.Vicente,MD
C t t St bi
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Constant StrabismusWorkup, acute presentation, nerve palsy
– (Case of newly acquired left CN 6 in a 55 yo male)
– Ischemic, GCA
– Neoplastic
• Invasive
• Paraneoplastic
• Compressive
• Nerve regeneration
– Longstanding breakdown.
– Sensory
– Degenerative CNS, Parkinson’s, MS
– Infectious
• Myositis (trichinosis)
– Iatrogenic
• Post non-strabismus surgery• Cataract, retrobulbar blocks (nerve damage vs. contracture)
• Glaucoma, valves
• Lasik
– Mechanical
• Trauma
• Blow out Fracture• Tumor G.Vicente,MD
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More Types of Strabismus
– Convergent, Esotropia• Accommodative
• Congenital or infantile
• Acquired, CN 6 palsies
– Divergent, Exotropia
– Vertical, Torsional and Oblique
• Parks 3 Step test• Superior Oblique Palsies
– Tucks vs. IO recessions
• Inferior Oblique Over action (V patterns)
• DVD’s Dissociated Vertical Deviation
– Complex Cases• Adjustable vs Fixed sutures.
• Re-ops – Different measurements based on eye fixation
• Optics
• Angle Kappa
G.Vicente,MD
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Alternate Cover test with Prism
Exotropia, Constant
Use prism to quantitate the
deviation.
Change prism power until
movement is neutralized.
Use this number to plan surgery
How much to operate…
G.Vicente,MD
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Exotropia
• Remember to measure while fixating at a
far distance.
• Also use +3.00 sph in front of each eye to
eliminate the accommodative convergencecomponent at distance.
• Consider 30 minute patch test to break
fusion and really see how bad the XT canget.
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How much to operate?
– How much to
operate
• Tables:
• Personal experience
• Dosages (surgical)• bilat , 2 muscles
• ie for ET 40PD recess 5.5mm both MR
• ET XT
• PD Rec Rst Rec Resect
• 15 3 3 4 2.5
• 20 3.5 4 5 3
• 25 4 5 6 4
• 30 4.5 6 7 5
• 35 5 7 7.5 5.5
• 40 5.5 7.5 8 6
• 50 6 8 9* 7• 60 6.5 8.5 10* 8
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Where to operate?
Option A: recess, loosen bilateral MR Medial Recti.
Option B: recess Left MR and resect, tighten Left Lateral Rectus LLR
RMedial RectusLMedial Rectus
L Lateral Rectus
G.Vicente,MD
L ET (65PD) bil t l MR
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Large ET (65PD) , bilateral MR
recession, and LLR resection
preop
1 month post op
3 d
post op
G.Vicente,MD
H h t t
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How much to operate
-Patient preference
Case of monocular 85 yoBF with sensory XT
one eye or two?
Pt wished to not have ODoperated, understood riskof under correction.
Therefore only recessed
LMR 7mm and LLR 6mm. Pt had some residual XT
15-20 PD, but was happy,therefore surgeon washappy too.
G.Vicente,MD
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Surgical Notes Sutures:
– Most stitches used in eye surgery are thinner than humanhairs.
– They will dissolve on their own over 6 weeks. They may makeyour eye feel scratchy for the first few weeks.
– The antibiotic ointment and a cool compresses will alleviatethis symptom if it occurs.
– Adjustable sutures What to expect after surgery
– Some double vision is normal for the first few weeks after eyemuscle surgery.
Precaution:
– General post op hygiene – Eye rubbing
– Can my child swim after his or her eye surgery?
Length of surgery and recovery
G.Vicente,MD
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Notes on Anesthesia
– Notes on Anesthesia
General
Pediatric anesthesia doctors
Risk of Gen. Anesthesia in children
Primary MD clearance
G.Vicente,MD
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Complications and Risks or surgery
Infection (1 in 3 years, Tx oral Abx)
Nausea (Tx: Phenergan, etc.)
Blood loss – (what blood loss, maybe a little more than corneal
surgery) Loss of sight? (globe perforation)
Scar tissue
Diplopia
Residual or consecutive strabismus Oculo-Cardiac Reflex – Bradycardia
– Tx: Atropine
G.Vicente,MD
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When to operate? Or …When NOT to operate?
• Prisms – Fresnels
– Permanent prisms
• Occlusion (non-operable, CNS disease)
• BCVA (sharp image will often help pt fuse)
G.Vicente,MD
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When not to operate cont.
• Botox – best for small, new, noncontractile strabismus, ie ischemic CN 6
palsy.
– Or very variable strabismus ie cerebral palsy, to preventcontracture and save time.
• Exercises, best for convergence insufficiency X(T)’.
• Small Magnitude (<8 PD)
• Tolerability, symptoms – head position, career, lifestyle
• Surgeon aggressiveness, cut, cut, cut• Pre-existing Amblyopia – (how much to treat before surgery?)
• Angle Kappa pseudo XT…
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How to operate
Go to Recession and Resection Lectures
G.Vicente,MD
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