basics, diagnosis and management of esotropia

2.  Derived from 2 greek words- ‘eso’ which
means ‘inward and ‘trepo’ means ‘turn’.

3.  Apparent convergent squint
 Angle kappa- negative
 Causes:
 1. Telecanthus
 2. Epicanthus

7. (A)-Symmetric central
Asymmetric –
(B) - Pupillary margin: 15°
(C) - Close to limbus: 30°
(D) -Beyond limbus: 45°

8.  Three commonly recognized stages:
 Esophoria
 Intermittent Esotropia
 Esotropia

9. ESOPHORIA

10.  Esodeviation that is intermittently controlled
by fusion mechanisms.
 Manifest under certain conditions such as
fatigue, illness and stress.

11.  Esodeviation that is not controlled by
fusional mechanisms so that deviation is
constant

12. ESODEVIATION
INCOMITANT
PARALYTI
C
RESTRICTIVE SPASTIC
CONCOMITANT
ACCOMODATIVE
PARTIALLY
ACCOMODATIVE
NON
ACCOMODATIVE
•Neurogenic
•Myogenic
•Musculofacial
•other
Refractive
Non refractive
•Essential infantile
•Essential acquired
•Acute comitant
•Microtropia
•Cyclic esotropia
•Sensory esotropia
•Nystagmus blockage
syndrome

14.  Esodeviations due to excessive convergence
associated with accomodation are called
accomodative esotropia.
ACCOMODATIVE
ESOTROPIA
REFRACTIVE
NON
REFRACTIVE
PARTIALLY
ACCOMODATIVE

15.  MOST CONSISTENT FEATURE:
VARIABLE ANGLE OF ESODEVIATION
WHICH INCREASES WITH THE EFFORT
FOR ACCOMODATION

16.  Uncorrected hyperopia
 To see clear at distance- they accommodate-
esodeviation for distance fixation.
 Normal AC/A- therefore ET same for
distance and near (within 15 PD)
 NO CONVERGENCE EXCESS
 Respond well to full cycloplegic correction of
hyperopia

17.  Usually mild to moderate hyperopia (+2 to
+6D)
 Very high hyperopia- donot accommodate-
bilateral amblyopia
 Apart from ET and amblyopia, they may
present with asthenopia due to constant
accomodative effort.

18. 6/6 6/6

20.  Heterophoria method
 AC/A= IPD+ (∆n- ∆d)/3
 Normal- 5-7.5pd/1D
 Gradient method
 AC/A= N-D/3
 Normal- 3-5pd/1D

21.  ET for distance + convergence excess
(>15PD) ET for near (at 33cm)
 High AC/A ratio

22.  No clinically significant hyperopia
 No accomodation for distance- no ET for
distance
 High AC/A ratio
 >15PD ET for near
 ‘Hyper accomodative type’

23.  Weak accomodative mechanism
 Over-accomodation
 Normal AC/A ratio
 Convergence excess type
 Remote NPA and NPC- whereas hyper
accomodative type have a normal NPA
 Seen in early presbyopes or cases under
mild cycloplegia

24.  2nd year of life
 Variable angle of ET, presence of
convergence excess and full cycloplegic
error should be looked for.

25.  Full cycloplegic correction
 If convergence excess- bifocals are
prescribed.
 The minimal plus add that corrects
convergence excess ET is added.

26. Full cycloplegic
correction/bifocals
Residual esotropia
Non-accomodative
element
Partially accomodative- require
surgery for the non- accomodative
part
MR recession with or
without retro-equatorial
myopexy. (Faden)

27. 1. Early onset- high risk of amblyopia
2. Large angle ET(30pd)
3. Free alteration/ cross fixation in alternators
and fixation preference of normal eye in
amblyopes
4. No significant refractive error
5. No Neurologic deficit
6. Confirmed only after 4-6 months

29. 7.May be associated with:
 IOOA (68%)
 Nystagmus (33%)
 DVD(50%)
8. Asymmetric optokinetic nystagmus:
Temporal to nasal- smooth
Nasal to temporal- cogwheel

30. A special characteristic of congenital esotropia - OKN
asymmetry
Temporal to nasal (T/N)
Smooth, following and
rapid refixation
Nasal to temporal (N/T)
Jerky inaccurate
movements
with halting refixation
OKN asymmetry is present in all infants but becomes symmetrical by 6 months.
Patients with congenital ET retain OKN asymmetry

31.  Ciancia syndrome
 Lang’s syndrome

32.  Early onset ET
 Bilateral abduction limitation
 Manifest-latent jerk nystagmus (fast phase in
the direction of fixating eye)
- Increasing in abduction; decreasing in
adduction
- Face turn towards fixating eye
- Fixating eye in adduction(null point in
adduction)

33.  Early onset ET
 DVD
 Nystagmus
 Excyclodeviation of non fixating eye
 May be associated with torticollis

34. DIFFERENTIAL DIAGNOSIS
Cranial nerve 6th palsy Doll’s eye manouvere
Duane’s retraction syndrome Changes in palpebral aperture,
upshoot/downshoots on adduction
CNS anomalies Down’s syndrome, Mobius, Cerebral
Palsy, Albinism
Accomodative ET/ Partially accomodative
ET
Cycloplegic refraction
Nystagmus blockage syndrome Inverse relation between amplitude of
nystagmus and degree of esotropia

35.  Unknown
 Multifactorial
 Heritable factors- monozygotic twins
showing esotropia
 Developmental anomaly in first 4 months

36.  Depends on treatment of amblyopia
 Full cycloplegic refraction under atropine 1 %
eye ointment
 Full hyperopic correction
 Occlusion

37.  Conventional full time, fully opaque occlusion
of dominant eye.
 At no point during the treatment, is binocular
viewing allowed.
 Thus, patching is done for 3:1, 4:1 or 5:1
days for a 3,4 or a 5 year old child
respectively.
 Above 6 years, the regime remains 6:1 for all
ages.

38.  Vision assessment done monthly. (fortnightly
in infants).
 End point: free alternation of the two eyes
which is equally maintained.

39.  Large angle ET- earliest/ 4 months of age
 Small angle ET- proper hyperopic correction
till 6 months or till examination can be done
satisfactorily.

40.  Associated inferior oblique ‘v’ phenomenon
 Amblyopia therapy
 DVD
 Nystagmus
 Eccentric fixation or uncorrected amblyopia
have unpredictable results.

41.  MR surgery is more effective LR surgery
 Mono-ocular recession-resection or bimedial
recession
 MR 1mm surgery corrects 3-4.5 PD of
deviation
 LR 1mm surgery corrects 2-3 PD of
deviation

42.  Onset after infancy
 No accomodative factors and no neurological
cause (excluded by CT/MRI)
 ‘acquired essential (non-accomodative)
esotropia.
 Basic type or convergence excess type
 Rarely divergence insuffiency may be present.
 Management- Surgery with better binocular
visual potential than infantile esotropia

43.  Ultra small angle ET
 Missed by ordinary methods of examination
 Usually have amblyopia of one eye with
variable levels of binocularity
 1. Primary
2. Secondary(residual deviations after
surgery)

44.  Macular scotoma
 Good peripheral fusion with fusional
amplitudes and gross stereopsis

45.  Small angle (<5˚) heterotropia
 Harmonius ARC
 Mild amblyopia
 Partial stereopsis
 Based on fixation pattern Cover test
Type 1 Central fixation Shows tropia
Type 2 Eccentric fixation without
identity
Shows tropia
Type 3 Eccentric fixation with
identity
Does not pick up a tropia

46.  Type 3- eccentric fixation with identity implies
that angle of anomaly is same as the
eccentricity of fixation.

47. CONSISTENT
 Amblyopia
 ARC
 Relative scotoma on
fixation spot
 Normal or near normal
fusional amplitudes
 Defective stereoacuity
VARIABLE
 Size of deviation (5˚-8˚)
 Foveal or non-foveal
fixation
 Relationship between
degree of eccentric
fixation and angle of
anomaly
 Presence or absence of
anisometropia
 Positive or negative
cover test

48.  Macular scotoma by Bagolini’s glasses or
4PD test.
 Presence of amblyopia and associated
refractive error should be detected.

49.  Treat amblyopia with occlusion therapy
 Good prognosis if treated in younger
children.

50.  Sudden presentation
 c/o diplopia
 2 types:
1. Those which manifest after the fusion has been
interrupted by a patch or occlusion for a short
time.
2. Those which have no such interruptions to
fusion but have very poor fusional control,
which may be further compromised by physical
or emotional stress.

51.  First type- spontaneously resolve within 6
months.
 Second type- Surgery/ prismatic
neutralisation in case of small angle ET.

52.  Regular cycles of presentation
 Usually 24-48 hours of squint alternating with
same duration of no squint.
 Squint days:
 1. large angle ET (40-50PD)
 2. sensory anomalies
 3. squint is consistent.

53.  No squint days:
 1. BSV with good fusional amplitudes
 2. No latent squints
Lasts for a few months to years before they
become fully manifest squints
Surgery as per deviation on squinting days
gives satisfactory results.

54.  Infantile ET is associated with manifest-latent
and latent nystagmus.
 However, there is a special form of nystagmus
which has a dampening mechanism with eyes
in adduction
 Inverse relationship between ET and
nystagmus
 Nystagmus is present when eyes are straight
and it disappears when eyes are locked in ET.
 Management: Faden with or without B/L MR
recession.

55.  Lost vision in one eye usually develops
squint over a period of time.
 XT or ET depending on convergence tonus
 XT- in first year and after 8-9 years of age
 ET- after first year upto 8-9 years of age
 Refractive error and accomodative status of
the straight eye needs to be evaluated
before planning any cosmetic surgery

57.  Refraction and proper prescription including
use of bifocals
 Use of prisms
 Purpose:
 Fusion and binocular vision
 Maintains relationship between
accomodation and convergence
mechanisms

58.  PROPER CYCLOPLEGIA
 PROPER PRESCRIPTION- full cycloplegic
correction with no over or under correction.
 BIFOCALS- In case of high AC/A ratio

60.  Glass prisms- upto 7-8 pd over each eye
 Fresnel prisms- upto 25-30 pd

62.  Miotics
 Cyclopegics
 Chemodenervation by botox

63.  Site of action- ciliary muscles
 Facilitates accomodation
 Reduces accomodative effort
 Hence, reduces accomodative convergence

64.  Di-isopropyl-flourophosphate (DFP)
 Phospholine iodide (Echothiophate)- 0.03%,
0.06% and 0.125%
 Demecarium bromide (Humorsol)

65.  Desirable end results after use of miotics is
proper binocular alignment at all times,
especially near work with accomodative
tasks.

66.  To make patients accept full hyperopic
correction
 To suppress accomodative convergence
mechanisms and stimulate divergence

67.  This is still under trial by Scott and McNeer
 Infantile esotropes if aligned before 6 months
can have good functional binocularity.
 While the surgical effect of botox in adult eye
muscles is transient, effect in early infancy is
permanent because of the changes in the
developmentally immature muscles.

68.  Initial overcorrection may restructure the
ocular motility balance to yield better result
ultimately.
 However on the negative side, associated
changes of oblique overactions/ AVpatterns/
DVD may still require surgical correction.

69.  PRE OP EVALUATION
 Assessment of vision and amblyopia therapy
 Measurement of deviation

70.  Weakening
 Strengthening
 Aim- symmetrizing and not symmetric
surgery

71.  To split amount of surgery across two recti
rather than single large surgery in single
muscle alone
 If AV, with obliques overaction- vertical
shifting of horizontal recti or slanting
recession and resection can be done

72.  Recession
• Conventional
• Hangback
• Adjustable
• Vertical transposition of horizontal recti
• Slanting recession
 Retroequatorial myopexy

73.  Muscle is disinserted and reinserted to a
point closer to its origin.
 Induces a slack/laxity
 Muscle becomes less effective
 Reinsertion to be done within its arc of
contact
 Max recession defined by functional equator-
depends on arc of contact

74.  Max recession MR- 6mm LR- 8mm in adults
 Children- MR 5.5mm LR 7mm
 Minimum MR 3mm LR 4mm

75.  Recession is done with long ends of the
suture between the site of insertion and the
muscle.
 This is indicated if supramaximal recession
is intended and its difficult to pass sutures
that posteriorly
 Or, there’s a risk of scleral perforation in high
myopes

76.  Weakening effect is more than a
conventional recession because of a central
(mid width) sag.
 A pseudotendon may form in the intervening
space around the sutures which may lead to
a late under correction.

77.  Ability to modify the position of a newly operated
muscle by use of adjustable sutures.
 Indications:
 Large angle deviations where results may be
inconsistent
 Reoperations/ previously injured muscles
 Incomitant starbismus with diplopia when precise
post operative results are desired.
 Mechanical limitaions as in dysthyroid orbitopathy
or musculofacial anomalies.
 Aberrant innervation in III nerve palsy or DRS

78.  Posterior fixation suture
 Musle is sutures posterior to insertion farther
than its limit of arc of contact.
 This shortens the lever arm and reduces the
action of muscle in its field of action.
 No change in primary position if no recession
is done along with Faden.

79.  MR- 12-14mm
 LR-16-20mm
 SR- 14-16mm
 IR- 14-16mm
 More effective on MR; least on LR

80.  Non accomodative convergence excess
esotropia (MR)
 Nystagmus blockage syndrome (MR)
 DVD (SR)
 Paralytic strabismus (contralateral synergist)
 DRS (contralateral MR)
 Additional weakening effect over recessed
muscle.

81.  Resection
 Advancement
 Transpositioning of adjacent muscles

82.  Shortens muscle length making itmore taut
 Improves efficiency by raising it to a higher
length tension curve
 Excision of tendinous part of the muscle.
 Therefore max limit for
 MR- 6mm
 LR- 4.5mm

83.  Strengthening procedure whereby muscle is
reinserted closer to limbus.
 Reverse of recession
 Indications:
 To correct consecutive squint in a recessed
muscle
 In paralytic squint, in addition to resection.

84.  Classification and management of esotropia in
children.
 What is faden operation.
 Accomodative squint- signs symptoms
investigations
 Management of accommodative esotropia.
 Investigations and management of concomitant
esotropia
 Describe the clinical features and management of
partially accommodative esotropia

85.  Management of alternating convesrgent
squint
 Monofixation syndrome
 What is microtropia? Discuss the types and
clinical features of microtropia
 What are the features and differential
diagnosis of infantile esotropia? When it
should be operated and its prognosis for
binocular single vision (BSV)?

86.  *Define essential infantile esotropia? Give at
least four differential diagnosis of essential
infantile esotropia and give at least two
differentiating features among them. 2+8
 25. Describe Faden’s operation as applied in
management of strabismus.
 *Describe the Clinical Features, investigations,
indications and surgical management of
infantile esotropia, and its post-operative
complications.

87.  Classify and give complete management of
esotropias in detail
 Define and classify esotropia. Management of a
6 year old patient with esotropia
 Classify esotropia. How wouldyou plan the
management of convergneceexcess esotropia
in a 5 year old child? Describe the choice of
procedure and surgical planning in detail.