Transcript Esodeviations-1390

esodeviations
An esodeviation is a latent or
manifest convergent misalignment
of the visual axes.
General consideration
 Esodeviations are the most common
type of strabismus.
 Accounting for more than 50% of ocular
deviations in the pediatric population.
Classification according to fusional
capability
 Esophoria is a latent esodeviation that is
controlled by fusional mechanisms.
 Intermittent esotropia is an esodeviation that is
intermittently controlled by fusional mechanisms
but becomes manifest under certain conditions,
such as fatigue, illness, stress, and covering 1
eye.
 Esotropia is an esodeviation that is not
controlled by fusional mechanisms, so the
deviation is constantly manifest.
Etiology
 Innervational.
 Anatomical.
 Mechanical.
 Refractive.
 Genetic.
 Accomodative.
Types of esodeviation
 Pseudoesotropia.
 Infantile (congenital) esotropia.
 Accomodative esotropia.
 Nonaccomodative acquired esotropia.
 Incomitant esotropia.
pseudoesotropia
 Is the false appearance of esotropia
when the visual axes are actually aligned
accurately.
 Flat, broad nasal bridge.
 Prominent epicanthal folds.
 A narrow interpupillary distance.
Infantile esotropia
 Classic congenital (essential infantile)
esotropia.
 Nystagmus and esotropia.
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1-Ciancia syndrome.
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2-Manifest latent nystagmus.
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3- nystagmus blockage syndrome.
Classic congenital (essential
infantile) esotropia
 Few children with classic congenital
esotropia are actually born with an
esotropia.
 Documented presence of esotropia by
age 6 months has been accepted as a
defining element of congenital esotropia.
 A family history of esotropia or strabismus is
often present.
 But well-defined genetic pattern are unusual.
 Other than strabismus, children with congenital
esotropia are usually normal.
 But up to 30% of children with neurologic and
developmental problems, including cerebral
palsy and hydrocephalus have esotropia.
Common findings
 Equal visual acuity.
 Alternate fixation.
 Cross fixation.
 Large angle esotropia , more than 30
prism.
 Amblyopia may be present when a
constant deviation of 1 eye is present.
 There may be an apparent abduction
deficit because of cross-fixation.
 The child ability to abduct each eye may
be demonstrated with the doll`s head
maneuver, by ratating the child, or by
observation with 1 eye patched.
 Inferior oblique muscle overaction and DVD
occur in more than 50% of patients, but are not
commonly recognized until age 1 year or older.
 Asymmetry of monocular horizontal smooth
persuit is normal in infants up to age 6 months.
 Patients with congenital esotropia have
persistent monocular smooth persuit
asymmetry that does not resolved.
pathogenesis
 The cause of congenital esotropia
remains unknown.
 There are 2 conflicting theories.
 Worth`s sensory concept was that
congenital esotropia resulted from a
deficit in a supposed fusion center in the
brain.
 According to this theory, the goal of
restoring binocularity was considered
hopeless.
 Chavasse disagreed with Worth`s theory and
believed the primary problem was mechanical
and potentially curable if the deviation could be
eliminated in infancy.
 Several studies report favorable sensory results
in some infants operated on between 6 -24
months of age.
 These encouraging results became the basis
for the practice of early surgery for congenital
esotropia.
management
 Cycloplegic refraction usually reveals 1-2 D of
hyperopia.
 Significant astigmatism or myopia may be
present and may require correction.
 Occasionally early onset accomodative ET may
be present and requires spectacle correction.
 A small-angle esotropia or intermittent may be
more likely to respond to hyperopic correction
than a large-angle, constant esotropia.
 Ocular alignement is rarely achieved
without surgery in a child with earlyonset esotropia.
 Surgery should be undertaken only after
correction of significant refractive error
and treatment of amblyopia.
 Failure to correct these problems may
compromise stable surgical alignment of
the eyes.
 Most ophthalmologists agree that
surgery should be undertaken early.
 The eyes should be aligned by age 24
months to optimize binocular
cooperation.
 Surgery can be performed in healthy
children between ages 4 and 6 months
to maximize binocular function such as
stereopsis.
 The Congenital Esotropia Observational
Study (CEOS) demonstrated that
patients with a constant and stable
esotropia of at least 40 P who present
between age 2 and 4 months are
unlikely to improve spontaneously.
 Smaller angles may be observed, as
they may improve spontaneously.
Surgical procedures
 Bilateral medial rectus recess is the most
acceptable procedure.
 Recess-resect of horizontal rectus of 1
eye is an alternative.
 More than 2 muscle surgery in 1 cession
may be done if the angle of deviation
would be more than 50 PD.
Botulinum toxin
 Botulinum toxin injection into the medial
rectus muscles have been used in the
treatment of congenital ET.
 Multiple injections may be required and
the long term sensory and motor
outcomes have not been shown to be
superior to those from incisional surgery.
The goal of treatment
 The goal of treatment in congenital
esotropia is to reduce the deviation to
orthotropia or as close to it as possible.
 Ideally, this results in normal sight in
each eye and in the development of at
least some degree of sensory fusion that
will maintain motor alignment.
 Approximately 1/3 of children will require
multiple surgeries.
 Alignment within 8P of orthtropia frequently
results in the development of the monofixation
syndrome.
 This syndrome is characterized by peripheral
fusion, central suppression, and favorable
appearance and is a successful surgical result.
 This small angle strabismus generally
represents a stable, functional surgical outcome
even though bifoveal fusion is not achived.
Accomodative esotropia
 Accomodative esotropia is defined as a
convergent deviation of the eyes
associated with activation of the
accomodative reflex.
 All accomodative esodeviations are
acquired.
Characteristics
 Onset generally between 6 months and 7 years,
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averaging 2.5 years of age.
Usually intermittent at onset, becoming
constant.
Often hereditary.
Sometimes precipitated by trauma or illness.
Frequently associated with amblyopia.
Diplopia may occur but usually disappears as
patient develops facultative suppression
scotoma in the deviating eye.
Types
 Refractive accomodative esotropia.
 Nonrefractive accomodative esotropia.
 Partially accomodative esotropia.
Refractive accomodative esotropia
 The mechanism of refractive
accomodative esotropia involves 3
factors.
 1- uncorrected hyperopia.
 2- accomodative convergence.
 3-insufficient fusional divergence.
 The uncorrected hyperopia forces the patient to
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accommodate to sharpen the retinal image.
Thus inducing increased convergence.
If the fusional divergence mechanism is
insufficient, esotropia results.
The angle of esotropia is generally 20 to 30 PD
and approximately equal at distance and near
fixation.
The average amount of hyperopia is +4.00 D.
Treatment
 Correction of the full amount of hyperopia,as
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determined under cycloplegia.
Any concomitant amblyopia should be treated
as well.
A gradual reduction of hyperopia correction
may be possible over time.
This reduction stimulates gradual increased
fusional divergence amplitude.
It can be result to discontinuation of spectacle
therapy in the future.
 Parents must understand the importance
of full-time wear of spectacle correction.
 The esodeviation, without glasses, may
even increase initially after the correction
is worn.
 It is helpful to explain that the glasses
help to control the strabismus, not cure
it.
Miotic therapy
 Miotic agents such as echothiophate
iodide has been suggested as a
substitute for glasses.
 Because of potential ocular and systemic
side effects, their use is usually confined
to children who are uncooperative in
wearing glasses at all or who spend long
hours playing in the water.
Surgical correction
 May be required when a patient fails to
regain fusion with glasses.
 Those who subsequently develops a
nonaccomodative component.
 However, the ophthalmologist must rule
out latent uncorrected hyperopia before
proceeding with surgery.
High accomodative convergence/
accomodative esotropia
 Patients with high AC/A have abnormal
relationship between accomodation and
accomodative convergence.
 Excess convergence tonus results from
accomodation, and esotropia develops in the
setting of insufficient fusional divergence.
 The angle of esotropia is greater at near.
 It can be reduced by +3.00 D bifocal lenses.
 Using of accomodative target in measurement
of the angle of esotropia is critical.
 This type of esotropia may be seen in patients
with high hyperopia, normal hyperopia,
emmetropia, or even myopia.
 In these latter groups the disorder is also called
nonrefractive accomodative esotropia.
 The refractive error in these patients averages
+2.25 D.
Management of high AC/A
esotropia
 Bifocals.
 Long-acting cholinesterase.
 Surgery.
 Observation.
Bifocals
 Is the most commonly used treatment.
 They should be prescribed in the executive or
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35-mm flat-top style with a power of +2.50 or
+3.00 D.
The top the segment should cross the pupil.
Conventional bifocals are preferred.
An ideal response is esophoria for near and
distance fixation.
An acceptable response is esophoria for
distance and less than 10 P of esotropia for
near fixation.
Long-acting choinesterase
inhibitors
 Starting the maximum strength (0.125%
echothiophate iodide drops) in both eyes
once daily for 6 weeks.
 If such treatment is effective, strength or
frequency should be decreased to the
minimum effective dose.
 Parents must be warned about the
potentially serious side effects of these
drugs.
Side effects
 Deletion of pseudocholinesterase from
the blood, which makes the patient
highly susceptible to depolarizing muscle
relaxants such as succinylcholine.
 Pupillary cysts: some ophthalmologists
prescribe phenylepherin 2.5% drops
twice daily concurrently to reduce the
risk of cyst formation.
surgery
 Some ophthalmologists advocate
surgery for high AC/A esotropia.
 Surgery can normalize the AC/A ratio in
these patients.
 It can be used in some patients, usually
adoalecents.
Observation
 Many patients will show a decrease in
the near deviation with time and
ultimately develop binocular vision at
both distance and near fixation.
 Some ophthalmologists will observe the
near deviation as long as the distance
deviation allows for the development of
fusion or if the patient is asymptomatic.
 For the long-term management of both
refractive and nonrefractive accomodative
esotropia, it is important to remember that
measured hyperopia usually increases until age
5-7 years.
 Therefore, if the esotropia with glasses
increases, the cycloplegic refraction should be
repeated and the full correction prescribed.
 After age 5-7 years, hyperopia may decrease,
and the full cycloplegic refraction in place will
thus blur vision and the prescription will need to
reduced.
 If glasses or drugs correct all or nearly
all of the esotropia, the clinician may
begin to reduce the strength of glasses
or drugs to create a small esophoria
when the patient reaches age 5 or 6.
 This reduction may stimulate the fusional
divergence mechanism to redevelop
normal magnitude.
Partially accomodative esotropia
 These patients show a reduction in the angle of
esotropia with glasses but have a residual
esotropia despite treatment of amblyopia and
provision of full hyperopic therapy.
 Sometimes, it results from decompensation of a
fully accomodative esotropia.
 In other instances the child may have had an
esotropia that subsequently developed an
accomodative element.
 An interval of weeks to months between
the onset of accomodative esotropia and
the onset of treatment often results in
some residual esotropia.
 Hence, prompt treatment of
accomodative esotropia may offer
substantial benefits.
 Patients with pure refractive
accomodative esotropia who have been
made orthotropic with glasses are less
likely to develop a nonaccomodative
component to their esodeviation than
patients with the type of accomodative
esotropia with a high AC/A ratio.
Treatment of partially
accomodative esotropia
 Amblyopia management.
 Prescription of the full hyperopic
correction.
 Surgery for the nonaccomodative portion
of esotropia.
Nonaccomodative acquired
esotropia
 Basic acquired esotropia.
 Acute esotropia.
 Cyclic esotropia.
 Sensory deprivation esotropia.
 Divergence insufficiency.
 Spasm of the near synkinetic reflex.
 Surgical consecutive esotropia
Basic acquired esotropia
 Esotropia that develops after age 6 months and
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that is not associated with an accomodative
component.
The amount of hyperopia is not significant.
The near deviation is the same as the distance
deviation.
Although most children with this form of
esotropia are otherwise healthy, CNS lesions
must be considered.
Therapy consists of amblyopia treatment and
surgical correction as soon as possible.
 When planning surgery for patients with
acquired esotropia, some ophthalmologists
advocate prism adaptation.
 Prism adaptation is a process of prescribing the
full hyperopic correction if indicated and adding
press-on prism to neutralize any residual
esodeviation.
 The patient wears the glasses with the press-on
prisms for 1 or 2 weeks and is then
reexamined.
 If the esodeviation increases with the
prisms, new prisms are prescribed to
neutralize the deviation.
 In some patients, the deviation continues
to increase and more prism is required to
correct it.
 Surgery is then planned for the full
prism-adapted deviation.
Acute esotropia
 Occasionally, an acquired esotropia is
acute in onset.
 The patient is aware of deviation and
frequently has diplopia.
 Artificial disruption of binocular vision,
(patching of an eye) for any reason is
one of the known cause of acute ET.
 Neurologic evaluation may be indicated.
 Most patients with acute onset of
esotropia have a history of normal
binocular vision.
 Therefore the prognosis for restoration of
single binocular vision is good.
 Treatment consists of use of prisms
during the period of observation and
later on performing surgery.
Cyclic esotropia
 Is a rare condition, with an incidence of
1:3000-1:5000 strabismus cases.
 Onset typically occurs during the
preschool years.
 The esotropia is present intermittently,
usually every other day (48-hour cycle).
 Variable cycles and 24-hour cycles have
also been documented.
 Fusion and binocular vision are usually
absent on the strabismus day, with
marked improvement on the straight day.
 Diplopia is unusual but may be seen in
older patients who are not able to
develop suppression.
 Occlusion therapy may convert the cyclic
esotropia into a constant one.
 Surgery is usually curative.
Sensory deprivation esodeviation
 Monocular vision loss from various
causes
 Cataract, corneal scarring, optic atrophy,
or prolonged blurred or distorted retinal
images, may cause an esodeviation.
 Anisometropia with amblyopia is
common in this type of esotropia.
 Obstacles preventing clear retinal images must
be identified and remediated as soon as
possible.
 Symmetric inputs must be accomplished at an
early age if irreversible amblyopia is to be
avoided.
 Any secondary amblyopia should be treated
before surgery if it is possible.
 Surgery for residual esotropia may be indicated.
Divergence insufficiency
 The characteristic finding of divergence
insufficiency is an esodeviation, generally in
adults, that is greater at distance than at near.
 The deviation does not change with vertical or
horizontal gaze.
 Fusional divergence is reduced.
 Divergence paralysis may represent a more
severe form of divergence insufficiency.
Divergence paralysis
 Can be divided into 2 form:
 1- primary isolated form.
 2- secondary form associated with other
neurologic problems, such as pontine
tumors or severe head trauma.
Primary isolated form
 Is frequently a benign condition.
 Symptom resolve in 40% of patients
within several months.
Secondary divergence paralysis
 May obtain relief from symptoms with
treatment of the underlying neurologic
disorder.
 Management of diplopia consist of baseout prism and sometimes surgery.
Spasm of the near synkinetic
reflex
 Patients can present with varying
combinations of excessive convergence,
excessive accomodation, and miosis.
 The etiology is generally thought to be
functional, but rarely, it can be
associated with organic disease.
 Patients may present with acute,
persistent esotropia alternating at other
times with orthotropia.
 The characteristic movement is the substitution
of a convergence movement for a gaze
movement on horizontal versions.
 Monocular abduction is normal in spite of
marked abduction limitation on version.
 Pseudomyopia may occur.
 Treatment consist of cycloplegic agents such as
atropin or homatropin, plus lenses for patients
with significant hyperopia and bifocals.
Surgical consecutive esodeviation
 Esodeviation following surgery for exodeviation
frequently improves spontaneously.
 Treatment includes base-out prisms, plus
lenses or miotics, alternate occlusion, and
finally surgery.
 Unless the deviation is very large or
symptomatic, surgery should be postponed for
several months because of the possibility of
spontaneous improvement.
A slipped or lost lateral rectus
 Produces varying amounts of esotropia.
 A slipped muscle should be suspected in the
case of consecutive esotropia with a large
abduction deficit following surgery on a lateral
rectus muscle.
 Surgical exploration and reattachment of the
muscle is required.
 Transposition procedures may be necessary
when lost muscles cannot be found.
 For slipped muscle, advancement of the muscle
is required.
Incomitant esodeviation
 The term incomitent esodeviation is used
when esodeviation varies in different
fields of gaze.
Sixth nerve (Abducence)
paralysis
 Congenital 6th nerve palsy is uncommon.
 Congenital 6th N. palsy is thought to be caused
by increased ICP associated with the birth
process and usually resolves spontaneously.
 6th N palsy occurs much more frequently in
childhood than in infancy.
 Older patients may complain of double vision
and often have a face turn toward the side of
paretic 6th N. to avoid diplopia.
 Approximately 1/3 of these cases are
associated with intracranial lesions and
may have associated neurologic finding.
 Other cases may be related to infections
or immunologic processes.
 Spontaneous benign lesions usually
resolve over several months.
Characteristics
 Usually equal vision of both eyes.
 The esotropis increases in gaze toward
the paretic muscle.
 Saccadic velocities show slowing of the
affected LR muscle.
 Active force generation tests weakness
of that muscle.
 Versions show limited or no abduction of
the affected muscle.
Work-ups
 A careful history to define any
antecedent infections, head trauma, or
other factors.
 CT scan and MRI are indicated when
neurologic signs or symptoms are
present.
 Patching of sound eye to prevent amblyopia of
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deviated eye in children.
Fresnel Press-ON prisms to correct the diplopia
in primary position.
Correction of any concurrent refractive error
specially hyperopia in children.
Botux injection into the antagonist MRM may
align the eye temporarily.
Spontaneous resolution may occur in more than
half of the patients with traumatic palsies.
Surgery
 Is indicated when spontaneous
resolution does not take place after 6
months or more of follow-up.
 In patients with some LR muscle
function, a large recession of ipsilateral
MR muscle with resection of the LR
muscle.
 In cases of total paralysis, muscle
transposition may be required.
Other forms of incomitant
esodeviation
 Medial rectus muscle restriction may
result from thyroid myopathy, medial
orbital wall fracture, or excessively
resected MRM.
 Incomitant esodeviation also may be
seen in Duane syndrome, Mobious
syndrome and other special forms of
strabismus.