Presenter

Definition

Non-Accommodative Esotropia or Non-Accommodative convergent Squint refers to the ESO-DEVIATIONS which are not primarily elicited by the direct influence of ACCOMMODATION.

Characterized by-Comitant Esotropia

-Acquired

-Onset after 6 months to 5 years

-Small to large angle deviation

-little or no hyperopia

-Normal AC/A ratio

-No neurologic or systemic sign or symptoms

SQUINT

Pseudo Squint

Manifest Squint (Tropia)

Latent Squint (Phoria)

Horizontal

Vertical

Cyclo

-Eso

-Exo

Comitant

Incomitant

Secondary

Accommodative

Non-Accommodative

Microtropia

Nystagmus Blockage Syndrome

Non-Accommodative Esotropia

Essential

Infantile Acquired

Basictype

ConvergenceExcess

DivergenceInsufficiency

Acute acquiredComitant eso

Acute strabismus afterArtificial interruptionof fusion

Acute strabismus Without Precedingdisruption Of fusion

Acute esotropiaof neurologic origin

Cyclic

Recurrent

A. Essential B. Acute Acquired Comitant

A. 1.ESSENTIAL INFANTILE ESOTROPIA

-Esotropia unilateral or bilateral

-occurs after birth within 6 months

Etiology

-Primary cause idiopathic

-Secondary causes are :

>Primary motor dysfunction associated with poor fusion

>family history of strabismus

>born prematurely

>a seizure disorder of hydrocephalus

FIXATION PATTERN INVESTIGATION

. Doll’s eye movement

. Alternate Patching

ASSOCIATED FACTOTS

Nystagmus; both manifest (rare) and latent (common)

Amblyopia ; not common

Inferior oblique Over Action

Abnormal Head Posture

DVD OR DHD

Asymmetric Optokinetic Nystagmus

Placing object on lateral side

Clinical Features Amount of Deviation =30- 40

Onset = after birth – 6 months (75% 2-3 months)

Fixation Pattern = cross fixation

Visual Acuity = Normal or Equal in Both Eyes

Refractive Error = may or may not present

TREATMENT Muscle Surgery – first check for associated factors and then wait for 6- 7 months for

surgery

Bilateral MR Recession or LR Resection

A. 2. ESSENTIAL Acquired Esotropia

a. Basic

b. Convergence

c. Divergence Insufficiency

a. Basic Esotropia

- Comitant Esotropia

- Amount of deviation is almost equal for distance and near in optically corrected eye

- Normal AC/A ratio

Etiology

-Innervational imbalance in muscle Excessive Tonic convergence

Muscle Imbalance

Improper Muscle Tone

CLINICAL FEATURES

Onset = after 6 months – 5 years

Amount of Deviation = almost equal for distance and near

Normal AC/A ratio

NPA within normal limit

Refractive Error = Hyperopia or Emmetropia

TREATMENT

(No glasses or miotics are helpful)

-First treat amblyopia

-Muscle Surgery (BL MR recession but depends on surgeon)

b. Convergence Excess Esotropia

- Comitant Esotropia

- More deviation at near than distance

-Divergence is normal ( Deviation at distance is neutralized)

-Not associated with any refractive error or High AC/A ratio

Etiology

Increased Innervational Tone of Converging Muscle

Clinical Features

onset – 1 to 5 years of age

AC/A ratio is normal

NPA is normal

Amount of Deviation is more at near than distance

Refractive Error may be Hyperopic or else EMMETROPIC

TREATMENT

Muscle Surgery ( BL MR Recession but depends on surgeon)

C. DIVERGENCE INSUFFICIENCY ESOTROPIA

Comitant esotropia in which deviation is more in distance than near and is associated with the weakening of the diverging muscle.

- Convergence for near is normal

- Chances of amblyopia is high

Etiology

Innervational imbalance in muscle action

Clinical Features

- After 6 months to any age

- AC/A ratio is normal

- NPA is normal

- Amount of deviation is more at distance than near

- Refractive Error is not associated

TREATMENT

Muscle Surgery is not reliable

Spectacles with BO prisms are helpful

Spectacle to be worn when distance vision is needed

B. ACUTE ACQUIRED COMITANT ESOTROPIA

Comitant esotropia which is always associated with diplopia.

It has acute onset and so can occur at any age.

It is not associated with paralysis of muscle

B.1. ACUTE STRABISMUS AFTER ARTIFICIAL INTERRUPTION OF FUSION

Patients may have no history of Squint.

Esotropia occurs after interruption of FUSION.

Fusion breakdown conditions are :-

i. Prolonged bandaging or Patching

ii. Occlusion in refractive amblyopia

iii. Swelling of eyelid followed by trauma

Postulate ; initially patients have ESOPHORIA which was being controlled

by well self functioning fusion.

CLINICAL FEATURES

Onset is acute , can occur at any age group

Diplopia is always present

Amount of Deviation is slightly more in near than distance

Associated with precipitating factors

TREATMENT

Refractive Error management

Systemic Illness management

Muscle Surgery

STRATEGY

Patient may close one or both eye to avoid diplopia

Refractive Error or Systemic Illness

BL MR Recession or BL LR Resection

Removal of Precipitating factors may dissolve deviation in some cases.Unless, Surgery is done

B.2. ACUTE STRABISMUS WITHOUT PRECEEDING DISRUPTION OF FUSION

Characteristics:

Acute onset

Diplopia

Relatively large angle of Esotropia

No sign of paralysis of muscle

No interruption in fusion is associated

Precipitating Factors

CLINICAL FEATURES

Onset is acute for all age group

Refractive error has minimal effect

Accommodative Element is minimal

Amount of deviation ranges from 20 - 60

Prolonged illness

ETIOLOGY

Idiopathic

TREATMENT

Refractive Error management

Systemic Illness management

Muscle Surgery BL MR Recession or BL LR Resection

STRATEGY

Removal of Precipitating factors may dissolve deviation in some cases.

Unless, Surgery is done

B.3. ACUTE ESOTROPIA OF NEUROLOGIC ORIGIN

Characterized by

It is always associated with neurological problems like

CLINICAL FEATURES

Etiology neurologic origin

Onset is acute

Refractive error Influence is minimal

No certain associations, sign or symptoms

Hydrocephalus

Brain Tumor

Craniocervical junction anomaly

TREATMENT

STRATEGYBeing a life threatening entity

Refer

To Neurologist

Treatment may dissolve Esotropia

If Not

Go for Surgery

C. CYCLIC ESOTROPIA

Characterized by

o A strabismic and no- strabismic phase of 24 hours each.

o This 48 hours of cycle is most common.

o However 72 and 96 hours cycle is also reported.

o Cycle may last from 4 months to several years.

o Unless treated , esotropia becomes constant.

CLINIAL FEATURES

Onset – early infancy

Amount of Deviation for both Near and Distance ranges from 40-70

Suppression in one eye

History of Amblyopia after being constant deviation

Fusional Amplitude is defective or absent

Fusion and stereopsis are normal

No manifest deviation, esophoria may be present.

Usually during early childhood

Non strabismic phase

Not related to

Visual Acuity

General or Ocular fatigue

Accommodation

Disruption of sensory fusion

Esotropia may be UL or B L

ETIOLOGY

Idiopathic

TREATMENT

Muscle Surgery

D. RECURRENT ESOTROPIA ( AKA Malignant Esotropia)

An unusual form of esotropia which reoccurs of the same angle even after multiple

operations.

No associations with conditions like :-

Increased uncorrected hyperopia

A deep seated ARC

Nystagmus blockage syndrome

An unstable AC/A ratio

Blind Spot Syndrome

CLINICAL FEATURES

Recurrent occurrence

AC/A Normal

Refractive Error influence is minimal

ETIOLOGY

Idiopathic

TREATMENT

Initially Muscle Surgery

BI Prisms mounted on spectacle