1. Examination of Eye

2. Examination of Anterior Segment Examination of Posterior Segment

3. Examination of Anterior Segment of Eye
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

4. Examination of Eye 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

5. Visual Acuity Definition-
It 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

6. Visual Acuity
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.

7. Snellen chart
Principle
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

8. Snellen Chart

9. Snellen Chart

10. Trial Frame

11. Occluder and Pin Hole

12. Snellen chart
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.

13. Procedure of testing
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.

14. Procedure of testing
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

15. Occluder

16. Procedure of testing
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+

17. Procedure of testing
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

18. Procedure of testing 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.

19. Procedure of testing Method
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

20. Pin Hole

21. Pin Hole Test 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.  

22. Near vision
Charts for testing near vision are 1) Snellen near vision chart - 2) Jaeger chart 3) Roman test type

23. Method of recording Near vision
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.

24. Examination of head posture
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).

25. Blepharophimosis Syndromen note chin elevation

26. Examination of forehead
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.

27. Examination of eye brows
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

28. Examination of the eyeball
Observe the following points
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

29. 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.

30. Proptosis

31. Shrunken (small) eye ball

32. Sunken Eye Ball

33. Examination of the eyeball
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.

34. Examination of the eyeball
c) Size of eyeball
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

35. Examination of the eyeball
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

36. Examination of the eyeball
Binocular Ocular Movements
Right side Left side
1 = Dextroversion; 2 = Levoversion; 3 = Elevation;
4 = Dextroelevation ; 5= Levoelevation; 6= Dextrodepression;
7= Depression; 8 = Levodepression