Download Examination of Eye

Examination of Eye
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Examination of Anterior Segment
Examination of Posterior Segment
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Examination of Anterior Segment of Eye
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Examination of Vision
Assessment of visual function
Forms of visual perception are form
sense , the field of vision, the light sense
and the colour sense, these senses are
checked with
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Examination of Eye
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Visual Acuity
Visual field examination with confrontation test,
perimetry (kinetic and static)
Dark adaptation – measurement of least
luminance required to produce a visual
sensation
Contrast sensitivity – is measurement of the
smallest distinguishable contrast ,it is
assessment of quality of vision
Colour vision –with lantern test (Edridge green
lantern) and Isochromatic charts
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Visual Acuity
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DefinitionIt is defined as the measure of the smallest
retinal image which can be appreciated with
reference to its shape and size .it is actually
measure of form sense.
Subjective examination of the function of eye
Central or direct vision
Distance vision with Snellen test type
Near vision with Snellen test type or Jaeger’s
test type
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Visual Acuity
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The principal of assessment is
measurement of spatial resolution of the
eye i.e. an estimation of ability of eye to
discriminate between two points.
DISTANCE VISION
Two distance point can be visible as separate
only when they subtend an angle of 1 minute
at the nodal point of eye.
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Snellen chart
Principle
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Each individual letter subtends an angle of 5
minutes and each component of letter subtends
an angle of 1 minute at the nodal point of eye
from the distance in meters written as numerical.
Snellen chart is having different number of
letters in different rows and the letter at top line
should be read clearly at distance of 60 m.
similarly the letters at subsequent lines as are
read at 36, 24,18,12,9,6,5mts respectively
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Snellen Chart
Snellen Chart
Trial Frame
Occluder and Pin Hole
Snellen chart
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Numerical convention is used for recording
visual acuity. In fraction, the numerator is
the distance at which the patient is sitting
from chart and the denominator is the
distance at which person (with normal
vision) should be able to read the last line
that person is able to read.
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Procedure of testing
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Patient is seated at the distance of 6 meters
from Snellen’s chart (distance of 6 mts is taken
as at this distance it is assumed that the rays are
almost parallel and patient exert minimum
accommodation)
The chart should be properly illuminated at
minimum of 20 feet candles. Patient made to
wear trial frame. It is adjusted according to
patient inter pupillary distance.
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Procedure of testing
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Ask the patient to read with one eye from the top
letter while the contra lateral eye is closed gently
with the patient arm or with occulder in the trial
frame.
Now patient is asked to reads the Snellen’s chart
and depending upon the smallest line which the
patient can read from distance of 6mts his vision is
recorded as 6/6, 6/9 ,6/12,6/18, 6/24, 6/36, 6/60.
But if patient is not able to see the top line from
6mts he is asked to come towards Snellen’s charts
step by step and vision recorded at 5,4, 3, 2, 1 mts
and noted as 5/60,4/60,3/60,2/60,1/60 respectively
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Occluder
Procedure of testing
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If patient is not able to read top line even at the
distance of 1 mts he is asked to count fingers of
examiner and his vision is recorded as CF3FT,
CF 2FT, CF1FT OR CF close to face .
If patient not able to count examiner finger close
to face then examiner waves or moves his hand
and asks patient whether he is able to see hand
movement or not. Visual acuity then recorded as
HM+
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Procedure of testing
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When patient cannot distinguish hand
movements the examiner notes whether the
patient can perceive light (PL) or not. If he
perceive light it is noted as PL +ve otherwise
as PL-ve. Also examiner then throw the light
from four directions (nasal, superior,
temporal, inferior)
and record accordingly. if present patient
perceive light from all directions it is marked
as PR (Projection of rays ) present or else
mark as absent or defective. The test is
repeated for the other eye in similar fashion
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Procedure of testing
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English chart
Landolt ring chart
This is the chart containing a series of broken
rings, with each gap subtending an angle of 1
minute at nodal point at a given distance.
It is used in illiterate patients.
E-chart – used in illiterate patients
Simple picture charts for children.
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Procedure of testing
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Pin hole test
Method
After noting vision unaided patient is asked to
read Snellen’s chart while holding a pin hole
(hole size is 1mm) exactly in centre of pupil in
front of eye.
Now patient’s vision is noted and similar pin hole
vision is recorded for other eye also
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Pin Hole
Pin Hole Test
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Interpretation
If patient vision is improved with pin hole it
means the poor acuity is due to refractive error.
If static acuity means may be due to structural or
organic cause.
If reduced the poor visual acuity may be due to
corneal opacity or lenticular opacity occupying
papillary area or macular pathology.
Near vision
Charts for testing near vision are
1) Snellen near vision chart 2) Jaeger chart
3) Roman test type
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Method of recording Near vision
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Ask the patient to sit with his back to the light
If the patient is using glasses for distance the
same number will be put on the trial frame.
Occlude one eye with an occulder
Ask the patient to hold the near vision by his
right hand at a distance of 25 to 33 cms.
Note the near vision as per the letter read
Repeat the test for the other eye.
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Examination of head posture
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Position of head, face and chin should be noted.
Note for elevation/depression of chin
Note for any elevation or depression of head
Face turn to right or left
In complete Ptosis (chin is elevated to uncover
the papillary area in a bid to see clearly)
In paralytic squint (head is turned in direction of
action of paralyzed muscle to avoid diplopia).
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Blepharophimosis Syndromen note chin elevation
Examination of forehead
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Look for increased wrinkling (due to over
action of frontalis muscle) in patient with
Ptosis.
Complete loss of wrinkling in one half of
the forehead is observed in patient with
lower motor neuron type of facial palsy
(seventh nerve palsy).
Facial asymmetry may be noted in
patient with bell’s palsy, musculo-facial
anomalies and facial hemiatrophy.
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Examination of eye brows
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Level of the two eyebrows may be
changed in a patient with Ptosis (due to
over action of frontalis)
Madarosis -Cilia of lateral one third of
eyebrows may be absent in patient with
leprosy and Myxoedema.
Scarring in and area around eyebrow
should be noted
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Examination of the eyeball
Observe the following points
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Position – normally the two eyeball are
symmetrically placed in the orbit in such a way
that a line joining the center point of superior
and inferior orbital margins just touches the
cornea
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Examination of the eyeball
a) Abnormality of the position eyeball can be –
Proptosis /exophthalmos – buldge of the
eyeballs –note
whether proptosis is –axial or eccentric
Reducible or non reducible
Pulsatile or non pulsatile
Enophthalmos – (sunken eyeball)
Absence of eye ball (clinical) is called
Anophthalmos.
Proptosis
Shrunken (small) eye ball
Sunken Eye Ball
Examination of the eyeball
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b) Visual axis of eyeball
Normally the visual axis of the eyeball is
simultaneously directed at same object
which is maintained in all the directions of
gaze.
Deviation is the visual axis of one eye is
called squint.
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Examination of the eyeball
c) Size of eyeball
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Measurement of eye is made by
ultrasonography (A-scan)
Size of eyeball is increased in conditions like
buphthalmos and unilateral high myopia.
Size of small sizes eyeball are-congenital
Microphthalmos, phthisis bulbi and atrophic
bulbi
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Examination of the eyeball
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d) Movement of eye ball
The movement are tested uniocular
(duction)as well as binocularly (versions)
in all the six cardinal directions of gaze.
Uniocular – Adduction, abduction,
depression, elevation, depression and
elevation in adduction and abduction
Binocular
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Examination of the eyeball
Binocular Ocular Movements
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6 7 8
6 7 8
Right side
Left side
1 = Dextroversion; 2 = Levoversion; 3 = Elevation;
4 = Dextroelevation ; 5= Levoelevation; 6= Dextrodepression;
7= Depression; 8 = Levodepression
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