4. Eye involved-uniocular/binocular
Direction of deviation-constant/intermittent
Mode of onset-sudden/gradual
Double vision
Precipitating factors
Duration
Type of deviation,photophobia,asthenopia,prior
treatment
Medical History,Birth Weight,Family History
HISTORY
7. • Undercorrected
visual acuity
• Best corrected visual
acuity
• Near vision
• Abnormal head
posture
• FIXATION
Central/Steady/Main
tained
VISUAL ACUITY
8. Grade Description of response
0 Not hold fixation with preferred eye
1 Holds fixation momentarily with non
preferred eye
2 Hplds fixation 2-3 sec with non preferred
eye
3 Holds fixation through a blink
4 No fixation preference,alternates
spontaneously
GRADES OF FIXATION
9. • Prism bars,
• Loose prisms (30 &45 PD)
• Occluder
• Torch light/Snellen’s chart as
fixation targets
• Bagolini’s striated glasses
• Red &green goggles
• Two Maddox rods
• Ophthalmoscope
• Retinoscope
• Synaptophore
• Hess chart
• Camera
• Indirect Ophthalmoscope
• VER
• ENG
Essentials Desirable
EQUIPTMENTS
10. • Head posture
• Ocular deviation
• Limitation of movements or the
extent of versions
• Fusional vergences
• Presence of binocularity
• Presence of diplopia
• Type of correspondence
• Suppression
• Amblyopia
• Stereopsis
Motor status Sensory status
EXAMINATION
11. • HEAD POSTURE
• Lid fissure: Palpebral fissure
• Facial symmetry
• Chin elevation/depression(vertical)
• Face turn right/left(Horizontal)
• Head tilt to right/left(torsional)
• Ocular torticollis, nystagmus,
• Marcus Gun phenomenon
• Bell’s phenomenon
MOTOR STATUS
12. Normal Right.
4th
Head posture in rightsuperior
oblique palsy.
The chin is down and the headtilted
left while the eyes look up to the
right. This compensates for boththe
vertical and the torsional defect.
13. •
Brown right eye
Face Up - Left
SR palsy or IR restriction one or
both eyes chin up
IR palsy with limited depression one or both
eyes Chin Down
18. Esodeviation
Exodeviation X’ X XT’ XT X(T)’ XT
RT hyper RH’ RH RHT’ RHT RH(T)’RHT
LT Hyper LH’ LH LHT’ LHT LH(T)’LHT
Heterophoria Hetrotropia
Near Distance Near Distance
E’ E ET’ ET
Intermittant
Near Distance
E(T)’ E(T)
COMMON SQUINT ABBREVIATIONS
19. Important to rule out existence of true
and apparent squint
True squint is misalignment of two
visual axis so that both do not meet at
the point of regard.
Apparent squint is appearance of squint
inspite of alignment :
Due to abnormal adnexal structures
Or abnormality between visual axis and
optical axis as in
telecanthus/epicanthus/
hypertelorism/euryblepharon.
OCULAR DEVIATION
21. Sherrington law:
A muscle will relax when its antagonist muscle (e.g.,
lateral and medial muscle) is activated.
Hering law:
The yoke m. are innervated equally by nervous system
in eye movement.
22. EYE POSITION FOR
EXAMINATION
Primary position:
With condition in which head being put vertically and
straightforward and two eyes looking straightforward.
Secondary position:
The two eyes being in adduction or abduction or elevation or
depression position.
Tertiary position:
Two eyes gazing in oblique directions (up or downward).
23. 1.Ability of both eyes to fixate target,
2.Ability of both eyes to have central
fixation,
3.Ability of both eyes to have no
gross/severe motility defect.
ALL THE TESTS ARE TO BE DONE IN
9 CARDINAL GAZES
PREREQUISITES OF COVER-
UNCOVER TEST
24. Subjective assesment is made on a
scale of 7 points+3 to -3 or 9 points
+4 to -4.
Adduction is normal when nasal
1/3rd of cornea crosses lower
punctum.
Abduction is normal temporal
limbus touches the lateral canthus.
LIMITATION OF MOVEMENTS
25. Vertical movements are difficult to
asses due to variability of palpebral
apertures.
Hypertropia inferior oblique:Mild
overaction
Appreciable on adduction:Moderate
overaction
Hypertropia primary position:Severe
overaction.
VERTICAL MOVEMENTS
26. HORIZONTAL VERGENCES:
Convergence and divergence.
VERTICAL VERGENCES:
sursumvergence and deorsumvergence
TORSIONAL VERGENCES:
Incyclovergence and excyclovergence.
MEASUREMENT OF VERGENCES
27. AN EXAMPLE OF PARALYTIC VERTICAL
STRABISMUS OF RIGHT INFERIOR RECTUS M.
36. Proper fixation target achieved at 33 cms for
near and 6 metres for distance
First fixation is observed
Covering of apparently fixating eye done and
other eye is observed. If other eye takes up
fixation,manifest squint is confirmed.
Covering apparent eye with translucent
occluder may show apparent eye deviating.
Refination of eye movement observed.
COVER TEST
37. Ruling out Latent squint
One eye is covered breaking fusion,eye
behind the cover deviates in case of
heterophoria.
Movement of eye observed on removal
of cover.
If deviation persistent, latent squint
with poor fusion is confirmed.
If recovery occurs, speed of recovery
noticed.
UNCOVER TEST
38. Infants who do not allow occluder or
hands close to their face,
Indirect occlusion/distance cover
test is used.
Fixation light or target is obstructed
for one eye by an occluder at some
distance away from the child and
deviation is observed.
INDIRECT OCCLUSION FOR
INFANTS
39. Corneal reflection to estimate
amount of deviation.
1mm shift signifies 5 degree of
deviation.
Test useful in non-fixating
eyes/in infants.
.
HIRSCHBERG’s TEST
HIRSCHBERG’S TEST
40. The prism bar is placed on fixating
eye to neutralise the amount by
observing corneal reflex in non
fixating eye
KRIMSKEY’S TEST
41. Placement of prisms in front of
deviating eye until corneal reflexes
are symmetrical
PRISM REFLECTION TEST
42. The apex of the prism should point
towards deviation:
ESOdeviation=Base Out
EXOdeviation=Base in.
PRISM BAR COVER TEST
43. Differentiates bifoveal fixation from
central suppression scotoma
1.In bifoveal fixation,prism is placed base
outwards with deviation of image
temporally and movements of both eyes
to left.
2.In left microtropia patient fixes target
and a prism is placed base out before left
eye.Image moves temporally in left but
within central suppression scotoma.
4 PRISM TEST
44. Example:Vertical deviation ,prism is
placed base up in front of right eye
for right hypotropia and base down
for right hypotropia.
After patch test
PRISM BAR COVER TEST
45. • With distance and near fixation:
Esotropia:Basic/convergence excess/ divergence insufficiency
Exotropia:basic/convergence insufficiency/divergence excess
• With/without glasses for accomodative element
• 9 cardinal positions of gaze for incomitance
• Up gaze 25 degrees,down gaze 35 degrees for AV pattern
• Alternative right and left fixation for primary and secondary
deviation of squint.
• Subjective and objective methods for retinal correspondence.
• .Prolonged cover to differentiate true divergence from simulated
divergence.
DIFFERENT ASPECTS OF
MEASUREMENT OF DEVIATION
49. Special motor tests
• Forced duction test
• Active forced generation test
• Three step test
50.
51.
52.
53. SPECIAL TESTS
Parks three-step test is very useful in the diagnosis of fourth
nerve palsy and is performed as follows :
A- first step. Assess which eye is hypertropic in the primary
position .
Left hypertropia may be caused by weakness of one of the
following four muscles : one of the depressors of the left
eye ( superior oblique or inferior rectus ) / elevators of the
right eye ( superior rectus or inferior oblique ) .
In a fourth nerve palsy the involved eye is higher .
54. B- step two . Determine whether the left
hypertropia is greater in right gaze or left gaze .
Increase on right gaze implicates either the right
inferior rectus or left inferior oblique .
Increase on left gaze implicates either the right
superior oblique or left superior rectus ( in fourth
nerve palsy the deviation is Worse On Opposite
Gaze – WOOG ).
55. C- step three .the Bielschowsky head tilt test ( isolates
the paretic muscle ).
With the patient fixating a straight ahead target at 3
meters, the head is tilted to the right and then to the left
.
Increase of left hypertropia on left head tilt implicates
the left superior oblique and increase of left hypertropia
on right head tilt implicates the right inferior rectus .
( in fourth nerve palsy the deviation is Better On
Opposite Tilt – BOOT )
58. In cases of misalignment,subject perceives
diplopia.
Diplopia can be tested by red green glasses
over right and left eye respectively with a
slit target.
Esodeviations cause uncrossed
diplopia(homonymous)and exodeviations
cause crossed diplopia(Heteronymous)
Hess Screen is also used for ocular
paralysis and restrictive conditions.
DIPLOPIA PRINCIPLE
59. .
DOUBLE MADDOX ROD
TEST one white and other
red,tilt neutralised by rotating
the rods.Change in axis givees
the exact cyclodeviation.
OBJECTIVE:
Indirect Ophthalmoscopy and
fundus photography are useful.
CYCLODEVIATION
60. Double Maddox rod test
-Red and green Maddox rods , with the cylinders vertical , are
placed one in front of either eye .
- Each eye will therefore perceive a more or less horizontal line
of light .
-In the presence of cyclodeviation , the line perceived by the
paretic eye will be tilted and therefore distinct from that of the
other eye .
-One Maddox rod is then rotated till fusion ( superimposition )
of the line is achieved .
61. -The amount of rotation can be measured in degrees
and indicates the extent of cyclodeviation .
-Unilateral fourth nerve palsy is characterized by less
than 10° of cyclodeviation whilst bilateral fourths
may have greater than 20° of cyclodeviation. This
can also be measured with a synoptophore .
62. EVALUATION OF OCULAR
TORSION
Anatomic (objective) torsion refers to
anatomic rotation of eye.
Subjective torsion refers to the patient’s
perception of rotation.
Comparison of anatomic and subjective
torsion can help determine the time of onset
of cyclovertical strabismus.
66. Dissimilar image tests
• Measures heterophoria
• Dissociates eyes for near fixation (1/3 m)
Maddox wing Maddox rod
67.
68. Corrective prisms are placed in front of deviating eye with patient fixing eyes
on target.
Prisms are slowly increased until angle overcorrected and diplopia occurs.
POSTOPERATIVE DIPLOPIA
TESTING
69. 1.Nearest point at which eye can
maintain binocular fixation is near
point of convergence
2.Near point of accomodation is
point at which eyes can maintain
clear focus.
NEAR POINT OF
CONVERGENCE/ACCOMODATION
70. DIPLOPIA:
Monocular diplopia due to astigmatism,subluxated lenses,large PI,corneal
oedema/facet.
Bagolini’s striated glasses can also help in ruling out diplopia.
Correspondence:
Normal retinal correspondence(NRC)
Anomalous retinal correspondence(ARC)
EXAMINATION OF SENSORY
STATUS
71. Sensory adaptation to squint to which
only one eye functions.
1.Bagolini’s striated glasses:
Symmetrical cross response: Absence
of manifest squint(NRC)
Manifest squint:ARC
Asymmetrical cross response:diplopia
present incommitant squint
Single line:suppresion response of one
eye
Cross response with gap:scotoma
SUPPRESSION
72. 4 dots :normal binocular response
5 dots:
esodeviation:uncrossed pattern(Red on right side)
Exodeviation:crossed pattern(red on left side)
Vertical squint:vertically displaced sets
3 dots:Suppression of right eye
2 dots:Suppression of left eye
WORTH’S FOUR DOT TEST
