1. Assessing vision

2. Purpose Definitions Responsibilities
Requisites

3. Procedure
Important points
Special cases
Points to remember

4. Purpose:
To document the vision accurately for each eye as vision recording is the most important documentation in a patient history
Documentation of vision is most important in many situations as legal, postoperative and injury and the M.L.O.P has to give utmost importance for this single test done by them.
To assess the ability to distinguish the shapes and details of the things one can see by measuring the visual acuity of the patient using vision testing charts.
To identify patients with decreased vision

5. Definitions
VA : Visual Acuity - the patient’s ability to see an object at a particular distance
Snellen chart : Eye chart used to measure visual acuity
PG : Present glass
HM : Hand movement
CFCF : Counting fingers close to face
PL : Perception of light

6. NO PL : No perception of light
Occluder : A device which blocks light to one eye
Amblyopia : Amblyopia is the medical term used when the vision in
one of the eyes is reduced because the eye has lost its potential to see due to some eye problem like squinting of the eye in young age
Aphakia : The absence of the lens of the eye
PH : Pin Hole

7. OD/RE OS/LE CC SC PR BCVA Oculus Dexter / Right Eye
Oculus Sinister/ Left Eye CC
Cum correction/ with correction SC
Sine correction/ without correction PR
Projection of Rays
BCVA
Best Correction Visual Acuity

8. Identifying the correct patient Preparing for vision assessment.
Responsibilities
Identifying the correct patient
Preparing for vision assessment.
Properly performing the vision assessment
4. Documenting vision assessment in the medical record

9. Requisites
Physical
Room size 6m or 3m
Multi letter Snellen or E chart ( 6m/3m )
Torch light
Occluder
Adequate illumination
Pin hole

10. Materials Required - Distance Vision Test
Snellen’s Chart
Occluder
Torch Light
Measuring Tape
6 metres/ 20 feet
Numbering Chart
Alphabet Chart
Tumbling ‘E’ Chart
Adequate lighting and a room with a minimum length of 6 metres or 20 feet

11. Skill and attitude
Skill to explain clearly
Empathy with the patient
3.Communication skill
4. Dedication to follow all steps

12. Procedure
Identifying the correct patient
Call the patient politely with respect.
Go near the patient and talk to the patient whenever possible
Use appropriate words to address them depending upon their age / status
Verify the name of the patient with the name in the medical record
Collect the ID card and verify that the M.R. No. in the ID card is same as in the medical record.

13. Process Flow of Vision Test Step 1 - Receive the patient
Correct treatment to the correct patient
1. Identify the correct patient
Reduces the fear and tension
2. Talk in polite manner
The patient may feel tired or with stress
3. Be compassionate
If not cooperative make the patient sit calm for some time and test vision
4. Stay utmost tolerant to get accurate findings

14. Preparing for vision assessment
Ensure good natural light or illumination on the chart .
Position the patient 6 / 3 meters away from the illuminated vision chart.
Make sure the level of the patient‘seye is equal to the level of Snellen chart to avoid parallax error
Ask for the general history of the complaint – time of onset, symptoms, the eye to be tested etc.
Check for past history of treatment taken
Check the usage of spectacles and duration.

15. Step 2 – History Taking What is your problem?
In which eye do you have the problem?
How long have you had this problem?
Do you wear spectacles? How long have you worn them?
When do you wear them?

16. Examine the anterior segment with torch light, Direct any emergency patient immediately to doctor

17. Step 3 – Torch Light Examination
Lens
Cataract
Cornea / Conjunctiva
Infection
Redness
Pain
Eyelids
Stye
Blepharitis
Chalazion

18. Explain the procedure to the patient.
I will show you a set of letters for you to read.
While reading cover the other eye and do not look through the other eye to make accurate measurement of your vision status
It is not a test that you have to pass, but a test to help us know how your eyes are working.
Keep your eye relaxed
Do not guess if you cannot see .

19. Have the patient fully cover the left eye with an occluder.
Assessing vision
Have the patient fully cover the left eye with an occluder.
Patient's hand should not be used; It may encourage peaking through fingers. Also instruct the patient to leave the eye not being tested open .
Closing the eye will cause squinting of eye being tested

20. Ask the patient to read the letters from left to right on every line down the chart until the patient misses more than half of the letters on one of these lines.
If the patient cannot read the letters due to language difficulties, use an E chart. Ask the patient to point in the direction, the ‘legs’ of the E are facing.This has to be explained clearly to the patient so that he or she understands if we are testing illiterate patient in camps

21. Instruction to patient
Capital letter E in decreasing sizes (arranged in different directions )
Instruction to patient
Look at the chart carefully and say in which direction the legs are pointing for the letter which I am pointing
In the example shown , it is pointing upwards

23. If the patient is not able to read even the largest letter at the top, stand from 5meter away from the patient and ask the patient to count the fingers five times.
If the patient responds correctly three times, stop and record the vision
If not reduce the distance by one meter and find the distance at which the patient is able to count the fingers

24. I If the patient is not able to count even at the shortest distance ( ½ m ), show the fingers close to face in front of the face (FCF – finger close to the face ) five times. If the patient responds correctly three times, record FCF.
If not move the hand in front of the face only five times and check
If the patient detects hand movement three times record HM

25. .
If the patient is not able to detect hand movements close to face, shine light on the eye from a distance of 33cm to 40cm ( only five times ).
If the patient is able to detect the light, then note pupillary action (constriction of the pupil) .If the pupil is not reacting, do not document as PL. ( Surgeries can not be done for a NOPL patient because there will not be any improvement in vision )
If the light is very close, patient will feel the heat and respond ‘yes’
Check whether the patient is able to detect the direction of light by shining light from the four directions – top, bottom, left, right

27. Repeat the same for other eye also
If the patient is wearing glasses, repeat the procedure with glasses for both the eyes.

28. .
Documentation
Record your name, date and time, in the medical record ,in the appropriate column
If the patient is able to read all the lines(7 lines), record visual acuity as 6/6
If the patient is able to read only six lines record the VA as 6/9
.Similarly, if the patient is able to read only five lines record the VA as 6/12

29. If the patient is able to read only four lines record the VA as 6/18.
If the patient is able to read only four lines record the VA as 6/18
If the patient is able to read only three lines record the VA as 6/24
If the patient is able to read only two lines record the VA as 6/36
If the patient is able to read only the first line record the VA as 6/60

30. On any line, if the patient reads the line partially, record the VA as partial for that line – eg. 6/36 P
If the patient is not able to read only one letter in a line record that - eg. 6/36 -1
If the patient is able only to count the fingers at a particular distance, record the VA corresponding to that distance – eg. for 3m, record VA as 3/60
If the patient is able to count fingers, close to face record as FCF
If the patient is able to detect only hand movement close to face, record as HM
If the patient is not able to detect hand movement but detects light, and there is pupil constriction, record as PL

31. If the patient is able to say the direction of the light, record as PR corresponding to the directions in which light is detected
If the patient is not able to detect light, record as NOPL .
Record the visual acuity for each eye separately with and without correction-
Eg. Right eye (OD) Left eye (OS)
6/18 6/12
6/6 P 6/ (with spectacles)

32. (Unable to detect light in the direction marked ‘-‘ )
Documentation for PR + + - + + - +
(Unable to detect light in the direction marked ‘-‘ )

33. If the patient ‘ vision is less than 6/6 use pin hole to check whether there is any improvement.
Based on the vision examination, escort the patient to the concerned unit/ specialty / doctors

35. .
Important points
Make sure the patient is viewing the chart properly / eyes are closed accurately / head position is correct /eyes are not squeezing etc.

36. Test the eyes one at a time, at first without any spectacles (if worn).
Test the ‘worse’ eye first (ask the patient out of which eye they see best).
This ensures that the minimum is read with the ‘worse’ eye, and more will be read with the ‘good’ eye. This means that no letters are remembered, which could make the second visual acuity appear better than it is.

37. Make sure that the patients do not press the occluded eye; this is not good for an eye that has undergone surgery.
It can also make intraocular pressure reading inaccurate
It will distort vision when the occluded eye is tested

38. Make sure vision is checked with and without glass for the patient who already uses spectacles or contact lens
While using charts use different types of charts for each eye ( number chart / letter chart ) to avoid recalling from memory
Wash your hands thoroughly after testing any infected patient.

39. Special cases
Handling dissatisfied patient
Listen politely and find out the reason for the dissatisfaction
Explain the importance of testing
Explain the reason for any delay and convince the patient

40. 2.Incase of vulnerable / wheel chair patient
Give priority and complete the testing as quickly as possible
3. Non- cooperative patient
Inform senior refractionist about the same.
Allow the senior refractionist to assess the vision

41. 4.Patients from other states
Find out the language of the patient
Get the help of a MLOP who is
fluent in that language to assess
vision

42. 5.Spend more time with the following patients
Unable to comprehend instructions due to language barrier
Difficulty in hearing
Uncooperative patients (who squeeze or close the eye during examination)
Paediatric patient

43. 5.Prioritising the patient
Injury
Redness ,pain
Sick patient
Corneal ulcer
Elderly disabled patient/ wheel-chair person
Appointment patient

44. For emergency patient (corneal injuries) direct the patient immediately to the doctor.
During camps, for vision measurement use a rope to measure the distance at which the acuity chart is placed. (6m)