OCULAR MOTILITY DISORDERS

DR. MANALI HAZARIKA SINGH

HETEROPHORIA

ESOTROPIA

EXOTROPIA

Heterophoria

• Misalignment , corrected by fusional capacity.

• Esophoria, Exophoria, Hyperphoria, Hypophoria,

• Cyclophoria –Incyclophoria & Excyclophoria

• Overstimulation of convergence with accomodnhyperopiaesophoria

Heterophoria - Symptoms

• Asymptomatic, eyestrain, blurring , headache.

• Manifest in conditions of fatigue.

• Exophoria m/c.

Cover & Alternate cover test for heterophoria

Maddox rod test• fix on a point light in the

centre of Maddox tangent• scale - 6 metres. • consists of many glass

rods of red colour set together

• placed in front of one

eye with axis of the rod parallel to the axis of deviation

Maddox wing test

• the amount of phoria for near

• at a distance of 33 cm.

• It is based on the basic principle of dissociation of fusion

by dissimilar objects.

Measurement of fusional reserve.

• synoptophore or prism bar.

• normal values of fusional reserve are as follows:

• Vertical fusional reserve: 1.5°-2.5°

• Horizontal negative fusional reserve (abduction

• range): 3°-5°

• Horizontal positive fusional reserve (adduction

• range) : 20°-40°

Treatment of phorias

• Spectacles

• Correct underlying refractive error

• Exercising the weak muscle against prisms or by using synoptophore

• Pen push ups

• Prisms in spectacles

• Finally, Surgery

Heterotropia

• Misalignment of the eyes is apparent

• Cyclotropia – Incyclotropia, Excyclotropia

Manifest strabismus may be-

Intermittent, Constant, Monocular, Alternating

Manifest squint is mainly of two types

Non-paralytic or comitant – There is no primary muscle impairmentDeviation is equal in all directions of gaze

Paralytic or incomitant – One or more muscle is weakened

Restriction of eyeball movement

Deviation different in different directions of gaze

Adaptation to strabismus – May be sensory or motorSensory adaptations-

Suppression- Inhibition of an image from one eye when both eyes are open

Abnormal retinal correspondence [ARC] – Here, non-corresponding retinal elements acquire a common subjective visual direction The fovea of the fixating eye is paired with a non-foveal element of the deviated eye. ARC allows some binocular vision

Motor – This involves adoption of an abnormal head posture

TYPES OF ESODEVIATION

• Pseudoesotropia

• Infantile esotropia

- Essential infantile

- Nystagmus & esotropia

– Ciancia

- Manifest latent nystagmus

- Nystagmus blockage synd

• Incomitant Esotropia

TYPES OF ESODEVIATION

Accommodative Esotropia

• Refractive (normal AC/A)

• Non refractive(high AC/A)

• Partially accomodative

Non accommodative acquired esotropia

• Basic • Acute• Cyclic• Divergence insufficiency • Sensory deprivation• Spasm of near

synkinetic reflex• Surgical (consecutive)

PSEUDOESOTROPIA

Pseudoesotropia due to wide bridge of the nose.  The eyes are perfectly straight as evidenced by the central location of the camera flash in the pupil of each eye.

ESSENTIAL INFANTILE ESOTROPIA

• Develops within 6 months of age

• Large angle eso >30∆

• Cross fixation

• Ref error-

+1-+2D

MANAGEMENT

• Astigmatism , myopia – correction

• Small angle eso- variable/ intermittent – hyperopic correction

• Large angle eso – constant –

correct ref error

treat amblyopia

surgery before 24 months (Recession of both MR)

ACCOMODATIVE ESOTROPIA

Convergent deviation assoc. with activation of accomodation reflex.

• Onset – 6m – 7y

• Intermittent at onset constant

• Hereditary, trauma, illness

• Amblyopia

REFRACTIVE ACCOMODATIVE ESOTROPIA

• Uncorrected Hyperopia (+4 TO +7D)

• Accomodative convergence

• Insufficient fusional divergence

• 20 ∆ - 30 ∆

Refractive accommodative eso

TREATMENT

• Full cycloplegic correction of the hyperopia

• Treat amblyopia

• Surgery – if eso fails to regain fusion with glasses or develops non accomodative component

NON REFRACTIVE ACCOMODATIVE ESOTROPIA

• High AC/A Ratio

• No Refractive Error

• Esotropia Is Greater For Near

TREATMENT

 A: The esotropia at near viewing is eliminated (B) with the use of bifocals.

BASIC/ACQUIRED

• > 6 months + no accomodative component

• Hyperopia not significant

• Near deviation = Distance deviation

• CNS lesions

• Rx- amblyopia treatment , surgery asap

ACUTE

• Acute onset of acquired type

• Diplopia

• Cause- patching for amblyopia,CNS lesion

• Prisms, surgery

CYCLIC

• Esotropia- every 48 hrs.

• Fusion and BSV absent on the strabismic day

• Occlusion converts cyclic to constant

• Surgery - best

SENSORY DEPRIVATION

• Cataract , corneal scarring , optic atrophy , anisometropia

• Amblyopia

DIVERGENCE INSUFFICIENCY

• Usually adults

• Greater at distance than at near

• Diplopia

• 40% - spontaneous

• Neurological lesion – pons, treatment of intracranial hypertnsion , steroids

• Base out prisms

SPASM OF NEAR SYNKINETIC REFLEX

• Excess convergence, accomodn & miosis

• Psychological

• Acute persistent eso alternating with ortho

• Atropine / homatropine, plus lenses with significant hyperopia and bifocals.

SURGICAL (CONSECUTIVE)

• Eso foll surgery for exo

• Slipped or lost muscle

• Base out prisms , lenses , miotics

EXODEVIATION

• PSEUDOEXOTROPIA

• EXOPHORIA

• INTERMITTENT EXOTROPIA

• CONSTANT EXOTROPIA

PSEUDOEXOTROPIA

• + ve pupillary axis is nasal to the visual axis

• - ve pupillary axis is temporal to the visual axis.

A, When the observer places his or her eye in line with the light located on the subject’s line of sight, the reflection of that light appears displaced nasal ward on the cornea. B, When the examiner brings his or her eye and the light into line with the patient’s pupillary axis, the reflection of the light appears centered.

EXOPHORIA

• Controlled by fusion.

• Detected – Alternate cover test – BSV interrupted.

• Asthenopia on prolonged reading.

• No treatment – unless – intermittent exotropia.

INTERMITTENT EXO

• Onset < 5 yrs.

• Manifest – inattention, fatigue, stress, distant visual target.

• Progress to

constant exo

• Amblyopia –

rare

INTERMITTENT EXO O/E

• Good control : XT manifests only after cover test & pt. resumes fusion rapidly.

• Fair control: XT manifests only after cover test & pt. resumes fusion only after blinking or refixating.

• Poor control: XT manifests spontaneously and remains manifest for long time.

INTERMITTENT EXO O/E

• Deviation at near is less than deviation at distance.

• Tenacious proximal fusion

CLASSIFICATION

• Intermittent exotropia– Divergence excess(XT DIST>NEAR)– Convergence insufficiency (XT NEAR >DIST)– Basic (XT NEAR=DIST)

TREATMENT OF INT. EXOT

• Non surgical

- Correction of mild myopia

- > 4D hyperopia

- > 1.5 D hyperopic anisometropia• Part time patching of dominant eye – 4-6

hrs /day, or alternate daily patching when no ocular preferance.- small/mod XT

• Base in prisms- not used since reduction in fusional vergence amplitudes.

TREATMENT OF INT. EXOT

• Ultimately require surgery- manifestation of the deviation >50% of the time.

• Before age of 7yrs – good sensory and motor.

• Recession of (BE) LR.

• Basic type – Recession of 1 LR + Resection of ipsilateral MR

CONSTANT EARLY ONSET EXO

• AT BIRTH

• NORMAL REFRACTION

• NEURO ANOMALIES

• TREAT- LR RECESSION & MR RESECTION

SENSORY EXO

• MONOCULAR/BINOCULAR VISUAL IMPAIRMENT – CATARACT

• EXO- OLDER CHILDREN OR ADULTS

• ESO- INFANCY

• TREATMENT – CORRECTION OF THE VISUAL DEFICIT , FOLLOWED BY SURGERY

CONSECUTIVE EXO

• DEVELOPS SPONTANEOUSLY IN AN AMBLYOPIC EYE OR FOLL. SURGICAL CORRECTION OF AN ESO.

Principles of surgery

• Cosmetic: proper alignment

• Functional: restore and maintain binocular single vision

Weakening procedures• Recession• Faden procedure• Marginal myotomy• Myectomy• Disinsertion• Chemical

denervation: botulinum toxin

Strengthening procedures

• Resection • Advancement• Double breasting/

tucking• Transposition of

adjacent muscles

THANK YOU