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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