Clinical Approach for The Congenital Esotropia, Inward deviation of the visual axes, with an onset before 6 months of age ..

1. Infantile Congenital Esotropia
Ahmed Essam Elsayed Farrag
4th year Medical Student
Mansoura Faculty of Medicine - Egypt

2. Strabismus is one of the most relevant health problems of
the world, and infantile esotropia is perhaps the most
visually significant yet the least understood. Infantile
esotropia is the inward deviation of the eyes noted before
the patient reaches age 6 months. It is associated with
maldevelopment of stereopsis, motion processing, and
eye movements. Amblyopia is a frequent consequence
of infantile esotropia. To date, its exact cause has yet to
be identified, and an effective treatment strategy is yet to
be formulated.
Background

4. Definition:
Inward deviation of the visual axes, with an onset before
6 months of age.
Background

7. Key features :
✓ Esotropia greater than 30Δ
✓ Cross-fixation
✓ No binocular vision
✓ Typical refractive error (between +1.50 and +3.00)
✓ Initially, similar deviation at distance and near fixation
Background

9. Associated features :
✓ Inferior oblique overaction
✓ Dissociated vertical deviation
✓ Latent horizontal and manifest rotary nystagmus
✓ Amblyopia in about one-third of patients
Background

11. The incidence of congenital
esotropia is roughly 1% in
most series
Epidemiology

12. may be more common in
children who have
neurological disorders ..
Epidemiology

13. Sex and racial distributions
are equal.
Epidemiology

14. Worth Theory :
- congenital absence of cortical fusion potential
- lack of binocular fusion
Etiology
Chavasse Theory :
potential for high grade stereopsis
primary motor misalignment
disruption of binocular vision

15. Amblyopia occurs in 25–40% of
patients, but the majority ‘cross-fixate,’
i.e., use the right eye to fix across the
nose to view objects to the left of the
patient, and vice versa ..
Ocular Manifestations

17. Size of the deviation :
the angle of deviation is usually larger
than 30 PD, and it is constant
Ocular Manifestations

18. Refractive errors :
Infantile esotropia with high refractive errors
(hypermetropia more than +2.50 diopters) can easily be
confused with accommodative esotropia, which may
occur as early as 6 months of age. Accommodative
esotropia manifests as eye inturning secondary to the
increased work of focusing through significant
hypermetropia.
Ocular Manifestations

19. Ocular rotation :
Some infants may show some limitation of abduction upon
initial examination of eye movements as a result of cross fixation.
However by eliciting doll’s head maneuver where
gentle spinning of the child stimulates a vestibular movement to
the opposite direction of the spin and a refixation saccade in the
same direction, full abduction can be elicited.
Ocular Manifestations

21. Identification of the proper deviation
in infancy without evidence of cranial
nerve palsies or systemic disease to
explain the deviation ..
Clinical diagnosis

22. ➢ Visual evaluation
✓ Understanding visual milestones and anatomic development is
mandatory for precise visual assessment of the child.
-- On average, by 2 months of age, the optic nerve
completes myelinization. At 3 to 4 months, the fovea
develops, and by 6 months iris pigmentation is
approximately 90% complete.
Diagnostic procedures

23. ➢ Visual evaluation
✓Methods to evaluate vision in infants include
fixation and following visual behaviors, Visual
evoked potential (VEP) testing, optokinetic
response, preferential looking and optotype
visual acuity depending on the child’s age and
level of cooperation ..
Diagnostic procedures

24. ➢ Motor evaluation
✓Cover/uncover testing is used to detect and quantify eye misalignment.
It is necessary to test the function of each extraocular muscle (ductions and
versions) and the patient’s control over the deviation.
Additional tests may include prism adaptation and
diagnostic occlusion ..
Diagnostic procedures

26. ➢ Sensory evaluation
✓ Complete sensory evaluation in a preverbal child is difficult.
Some signs may give a clue about the sensory development and the prognosis of the condition.
✓ Detection of fixation preference for one eye can be performed
by the use of vertical prism test (10-prism diopter test).
✓ Optokinetic response to detect smooth pursuit and saccade
eye movements will aid in the diagnosis of amblyopia ..
Diagnostic procedures

27. ➢ Pseudoesotropia
➢ Congenital sixth nerve palsy
➢ Nystagmus blockage syndrome
➢ Type I Duane’s syndrome
➢ Ciancia syndrome
➢ Congenital fibrosis syndrome
➢ Mobius syndrome
➢ Infantile Myasthenia Gravis
➢ Associated with neurologic diseases e.g. cerebral
palsy, periventricular encephlomalasia
Differential diagnosis

28. Pseudostrabismus. This results from a flat nasal bridge, wide epicanthal folds, and small interpupillary distance.

29. Treatment
The theoretical goals of treatment include:
• excellent visual acuity in each eye;
• perfect single binocular vision in all gaze positions at
distance and near;
• a normal esthetic appearance.
All are obtainable except for perfect single binocular vision,
because:
(with rare exceptions)these patients, even with early
treatment, do not view with both foveae simultaneously.
However,
most obtain peripheral fusion and the monofixation syndrome and
generally stable alignment.

30. Treatment
Medical therapy :
Occasionally infants with small angle esotropia
<30 PD may be corrected with
hypermetropic spectacle correction.

32. Treatment
 Medical therapy :
-The timing of amblyopia treatment in relation to eye
muscle realignment surgery is debatable ..
-Some surgeons treat amblyopia before performing
surgery to create a stronger visual drive for
straight eyes and thus better outcomes ..
-Amblyopia occlusion treatment after the eyes are
aligned can interfere with the exercise of binocularity ..

33. Treatment
 Medical therapy :
However, some surgeons may opt to surgically
realign the eyes prior to amblyopia therapy if
strabismic amblyopia is suspected ..
Early re-alignment has been
shown to lead to improved
sensory outcomes ..

35. Treatment
 Medical therapy :
Stability of the esotropia angle is assessed prior
to surgical intervention ..
Prism adaptation testing (PAT)
may assist in this determination ..

36. Prism adaptation is defined as
the preoperative wearing of
Fresnel prisms to offset the angle
of esotropia with adjustment of
prism power over time to
accommodate buildup to larger
angle of esotropia, until fusion is
achieved or it is demonstrated
that fusion cannot be attained ..

37. Treatment
Once a correction
target angle of
esotropia is determined
surgery can be
undertaken ..

38. Treatment
 Surgery:
Theoretically, the earlier
the surgery is performed
the better the potential for
binocular function ..

39. Treatment
 Surgery:
However technically the surgery is
more difficult earlier in infancy
because of the small size of an
infant’s eye and orbit, in addition
to the lack of stability of the
deviation and the possibility of
spontaneous resolution ..

40. Treatment
 Surgery:
Parents should be aware that the goal
of treatment is to get the eyes aligned and
encourage the best sensory development
possible,
which might take more than one
surgical procedure..

41. Treatment
 Surgery:
The standard approach for treatment is
bilateral medial rectus recessions which
weakens the medial recti ..
Alternately, a medial rectus recession with an ipsilateral lateral
rectus resection can achieve the same effect ..
Botulinum toxin injection into the medial recti to
weaken them has also been used, but studies have
shown mixed sensorimotor outcomes when compared
to traditional incisional surgery ..

45. Surgical Follow up
After surgical realignment, patients are usually advised to
return within 2 weeks following surgery to assess eye
alignment and the ocular healing process ..
Intraocular infection is rare following strabismus surgery
Patients should be followed closely for amblyopia,
even if they achieve good motor alignment .

46. Complications
Undercorrection and overcorrection are
the most commonly noted complications.
Many of these are transient.
Other less common complications include perforation of
the sclera, lost or slipped muscles, infection, anterior
segment ischemia, postoperative diplopia, conjunctival
granulomas and cysts .

47. Prognosis
Untreated infantile esotropes can develop
excellent vision in each eye, but bifoveal fixation
with full binocular function will not be achieved ..
Therefore, they will have poor depth perception and atypical appearance .
When infants undergo early surgical intervention, they have
a chance of better alignment and stereopsis outcomes ..
Amblyopia, residual esotropia or consecutive persistent
exotropia may develop and should be addressed early to
get the best possible visual and fusion potential ..

48. Take Home Messages
Characteristics of Congenital Esotropia :
• Esotropia (10.00 to 90.00 D)
• Alteration or Fixation Preference
• Neurologically Normal
• Hyperopia Correction Does not Eliminate Esotropia
• Confirmed by The 6th Month
• Best Treatment Results in Subnormal Binocular Vision

49. Thank You !