ophthalmology exam Flashcards
what to do on intro and 3 topics of measuring acuity
WIPER QQ
Enquires about corrected vision
Enquires about visual difficulties
1 - distance vision
2 - pin hole test
3 - near vision
The introduction and obtaining consent are the same. However fundoscopy is one of the few examinations were you encroach on your patients personal space. You usually perform it in a darkened room and your face including your lips/mouth end up being very close to your patients face. It is always a good idea to ask if your patient would like a chaperone and also to debrief them. Tell them that the examination involves standing quite close to them and that at all times they should remember to breath normally (you’ll find both the patient and you are holding your breaths).
testing Distance vision
- Sit the patient at a standard distance -‐‑ 6metres (unless using modified chart)
- Test each eye separately by covering one of the eyes
- Ask patient to read letters on chart. The lowest correct line is their distance visual acuity.
- Unaided visual acuity is measured first (no glasses).
- Corrected visual acuity measured next (with glasses).
Assesses with pinhole
Examiner: Ask candidate how to record reading (i.e. distance over line read)
Examiner: Ask candidate how to conduct rest of examination if the patient cannot see
• If no letters seen test ability to count fingers, then hand movements, then perceive light.
The pin hole test
If the vision falls below 6/6 use the pin hole test to tell if the cause of reduced vision is due to refractive error. If reading through the pin hole occluder the patient is able to read further down the chart they have an uncorrected refractive error.
Near vision
This is usually tested using a book of standard test types. (If these are not available most
newspaper text is N8 and headlines N12).
• With glasses on if required occlude one eye and ask patient to hold book at
comfortable distance and read smallest text that they can see.
• Repeat with other eye.
How to record visual acuity
Distance Visual Acuity is recorded as a fraction
The numerator is the distance from the chart in metres.
The denominator is the number written on the chart
i.e 6 (metres)/ 6 (line reached on chart)
The acuity recorded must reflect how this measure was achieved. how?
If glasses were worn the number is followed by – C gl
If glasses were not worn (but usually are) the number is followed by-‐‑ S gl
If contact lenses were worn, the number is followed by – CCL
If acuity is achieved by pinhole, the number is followed by – C PH
Near visual acuity is recorded according to the smallest size text which could be seen e.g. N4
acuity for patients who dont speak english
For patients that do not speak English use the Sheridan-‐‑Gardiner test. This shows single
letters which the patient can match to letters on a hand held chart.
first thing you do in the exam
W -‐‑ Wash your hands.
I -‐‑ Introduce yourself to the patient
P -‐‑ Permission. Explain that you wish to perform an examination of their eyes and
obtain consent for the examination. Warn the patient beforehand that you will need
to stand quite close to their face to be able to look into the back of their eyes and
check that they are comfortable with this.
Pain. Ask the patient if they are in any pain and to tell you if they experience any
during the examination.
E -‐‑ Expose the necessary parts of the patient. The face and neck should be exposed.
R -‐‑ Reposition the patient. In this examination the patient should be sitting in a chair
what do you do after WIPER in ophthal
Inspection
Is the patient wearing glasses/contact lenses?
Are there any signs of eye disease, e.g. cataracts, pupillary abnormalities, conjunctival injection etc?
fundoscopy - how do you Set up the ophthalmoscope
- Ideally the room should be dimly lit 4. Dim the lights – if necessary, use tropicamide drops 0.5% to dilate the patient’s pupil. check for a hx of glaucoma.
- Switch on the ophthalmoscope.
- Shine the light on your hand and select a large aperture.
- Rotate the focusing wheel and set it on zero.
- Keep your index finger on the focusing wheel.
- Ask the patient to remove their glasses [not contact lenses].
- It is optional to take off your own glasses.
- Ask the patient to look at a distant object straight ahead.
- Warn the patient that you will shine a light into their eye.
Explains procedure sufficiently
Mentions dimming the room, adjusting for corrected vision
Performs a brief external eye and general examination
Checks aperture and light setting
fundoscopy - Red reflex
Look through the ophthalmoscope and illuminate the pupils one at a time. The pupil should
appear red-‐‑ this is called the red reflex. Absence of the red reflex can indicate certain
conditions, e.g cataracts, retinoblastomas.
Performs red reflex at 1m
fundoscopy - Examining the retinas
To examine the right eye, hold the ophthalmoscope in your right hand and visa versa. Stand at arms length from the patient and gently rest your other hand on the patient’s forehead with your thumb on their eyebrow (warn them before doing this).
• Locate the optic disc and assess its colour, margins and cup to disc ratio ·∙
Cup to disc ratio (enlarged = glaucoma)
Colour (grey/pale = optic atrophy for example in MS)
Contours (swelling = papilloedema)
Neovascularisation (new vessels)
• Follow the major vessels and assess their tortuosity and dilation ·∙
• Examine the peripheral retina by asking the patient to look up, down, right and left.
Look for the presence of exudates, haemorrhages, pigmentation ·∙
• Locate the fovea (macula) by asking the patient to look directly at the light
- Observe for:
Hypertensive retinopathy signs (Check the vessels for 1. silver wiring, 2. AV nipping, 3. cotton wool spots, 4. papilloedema)
Diabetic retinopathy signs (dot and blot haemorrhages, cotton wool spots, neovascularisation, retinal fibrosis, hard exudates (cholesterol/lipid))
Other characteristic appearances (e.g. drusen (macular degeneration), pigmentation (retinitis pigmentosa) etc)
Macula: It lies temporaly to optic disc and is visualised by asking the patient to now focus on the light (i.e. look straight into the ophthalmoscope) of the ophthalmoscope. Should be pink (dark = macular degeneration).
You may also see photocoagulation (laser) scars
- Repeat the process to examine the patient’s left eye. Hold the ophthalmoscope in your left hand, look through it with your left eye to examine the patient’s left eye. Instruct the patient to look to a distant object on their right.
fundoscopy - what do you do after examining the retinas
turn on lights, Finally explain to the patient that you have finished and thank them for their cooperation.
Finishing Off Thanks the patient and appropriately closes consultation Diagnosis Able to describe retina and pathology States correctly the most likely diagnosis States suitable investigations States suitable management States suitable treatment
If patient’s pupils are dilated, they should not drive for at least two hours. If they do not have a relative with them, they should rest until they feel their vision is back to normal.
You then turn to the examiner and say: I would also like to:
• Take a full history
• Assess visual acuity and colour vision, visual fields, pupillary reflexes and extraocular movements
• Do a full neurological examination
• A slit lamps examination and if necessary get an OCT scan
Optical Coherence Tomography (OCT) is a non-invasive diagnostic technique that renders an in vivo cross sectional view of the retina. OCT utilizes a concept known as inferometry to create a cross-sectional map of the retina that is accurate to within at least 10-15 microns
order of things for fundoscopy
1 - WIPER 2 - inspection 3 - set up ophthalmoscope 4 - red reflex 5 - examine retinas
How is visual acuity recorded?
The visual acuity is expressed as the ratio of the distance between the patient and the card (usually
6m) and the figure on the chart immediately above the smallest visible line. An acuity of 6/18 therefore
means that, at 6m from the chart, the patient is able to read down to only the 18m line. Make sure the
patient wears glasses if they contain a distance correction. If the glasses are not available, reading
through a pinhole will correct for any myopia.
If the patient is unable to read the 60m line at 6m, they can redo the test at 3m. The visual acuity for
that eye will be recorded as 3/?. A visual acuity of less than 1/60 can be tested using fingers or light
perception.
