Examination of eye

Question 1

What is including in full examination of the eye (12)

full examination for maccs in bold (8)

Answer 1

-visual acuity - distance and near - with and without glasses

-visual fiels

-colour vision

-ocular movements - movement test, squint tests

-pupils - inspect, direct and consentual reflexes, swinging light test, accomodation

-anterior segment > conjunctivia, cornea, AC,iris, lens. can also inspect vitreous media

-red reflex

-fundus > optic disc, retinal vessels, macular, retina

• proptosis and enopthalmosis
• lids and lacrimal apparatus
• orbit
• intraocular pressure

Question 2

standard visual acuity testing with 6m snellen. you can get 3m snellens where they stand 3m. for full examination test pt with glasses on and off. for MACC glasses off

• illuminate snellen and ask pt to stand where (1)
• ask pt to cover one eye and read what (1)
• record visual acuity. numerator is (1) denominator (1). record lowest pt can read fully eg 6/6. if pt can read some from next line record as +however many. eg 6/6+2.
• if no text can be read try with (1)
• if no text can be read with pin hole perform assessment of poor vision (3)
• what is normal vision (1) what does the number of line mean on snellen (1) define visual acuity (1)

-can also test for near acuity. use chart of sentences of different sizes and pt to read the smallest one they can holding chart at their own comfortable reading distance

Answer 2

• glasses on
• illuminate snellen and ask pt to stand 6m
• ask pt to cover one eye and read smallest line they can
• record visual acuity. numerator is distance from chart distance. denominator is smallest line they can read. record lowest pt can read fully eg 6/6. this is the VA ratio. if pt can read some from next line record as +however many. eg 6/6+2.
• if no text can be read try with pinhole
• for each eye duh. ask how many fingers you are holding up at 1m. ask if they can tell if yo are moving your hand. can they detect light with a pen torch.
• normal vision is 6/6 (equiv to ‘20/20’) the number of the snellen line means normal person could read it from that number of metres. ie the text at the top is 60 so a normal person could read it at 6m. visual acuity refers to clarity of vision.

Question 3

cover same eye as pt. sit opposite.

• basic examination (1)
• visual fields (1)

>common pathologies to know - hemaniopia, bitemporal hemanopia, quandrantinopia, central scotoma

• visual fields for colour (1)
• map out blind spot with pin

Answer 3

• ask pt to tell you how many fingers you are holding up in 4 fields for each eye.
• visual fields use white pin. hold equal distance between you with outstretched arm and compare with your fields. bring in pin from periperhy of each quadrant until they can see it. continue through whole quadrant for each. may have central loss .
• visual fields for colour using red pin. ask pt when tip turns from dull to bright red
• map out blind spot

Question 4

-test squinting. what is a manifest squint(1) how to test (2) what is a latent squint (1) how to test(1) image attached shows types of squints. nb add approprate suffix -tropia or -phoria

-test movements. move finger how (1) assess what at each axis (3)

-when observing movements what to look for (4)

Answer 4

-assess for squint / strabismus. = abnormal alignment of eyes. if it is normal for pt to wear glasses on keep them on

>observe for a manifest squint/tropia = one that is always present. observe at rest pt looking straight ahead. perform the cover-uncover test to observe for mild manifest squints. cover one eye and observe the other for squint, positive if movement of the misaligned eye back to alignment.

>test for latent squint/phoria = this is a tendency for both eyes to deviate on dissociation. the alternative cover test can induce it. quickly cover and uncover each eye. observe for movement back to alignmend in eye that has just been covered. this is positive.

-test movements Ask the patient to keep their head still and follow pen torch/you fingers with their eyes.assure you can see the reflection of the torch in both eyes during movement so you know pt can see it​. glasses off as they will distract.

• Move your finger through the 9 axis of eye movement. at end of each test unilateral movement by covering one eye and moving torch along axis. do cover/uncover test. and alterating cover test at end of each too.
• Observe for

>restriction of eye movements eg inability to abduct eye in abducens nerve palsy

>nystagmus = rapid involuntary movements of the eyes. physiological nystagmus is often observed at the extremes of gaze = end point nystagmus

>additional squints

>double vision

Question 5

• what lighting for pupil examination is best (1).
• inspect (3).

>what is aniscoria. (1) what is difference between physiological and pathological aniscoria. (1) how to test (1)

-reflexes

>how to test direct pupillary reflex (1) causes of abnormal (3)

>how to test consentual pupillary reflex (1) causes of abnormal(2)

^if there is no defect in the afferent arc of pupil pathway these will be equal. if unequal = afferent pupil defect.

>how to do swinging light test.(1) what defect does this test for.(1) what is an abnormal response.(1) causes(1)

-accomodation/near reflex how to test (1)

Answer 5

• dimly lit room best
• inspect for size, shape, symmetry.

>aniscoria is difference in size of pupils. pysiologically present in 20% population. difference is physiological unequal pupils stay the same in difference in size if background illumination is altered. test by measuring size of both in dim lighting then measuring size of both in bright lighting. if physiological, will differ by same length each time.

-reflexes

>direct - shine light into the pupil and observe constriction that pupil.

an abnormal low or lack of constriction may suggest pathology of optic nerve, brain stem, drugs

>consentual reflex - again shine a light in pupil but this time observe the contralateral pupil. a normal consensual response involves the contralateral pupil constricting.

lack of a normal consensual response may suggest Damage to one or both optic nerves, Damage to the Edinger Westphal Nucleus

>Swinging light test - Move the pen torch rapidly between the 2 pupils. may detect a relative afferent pupillary defect (RAPD) - there is paradoxical dilatation of the affected pupil when light is shining into it , it should normally constrict.

• RAPD is caused by damage of optic nn ie lesion between the retina and optic chiasm, eg optic neuritis in multiple sclerosis. it is aka “Marcus-Gunn” pupil*
• -*accomodation / near reflex. ask the patient to focus on a distant object. then ask them to focus on a much closer object eg pen. a normal accommodation reflex involves constriction and convergence of the pupils .

Question 6

• intro, consent, hands.
• ask pt to look where.
• do what with glasses.
• using opthalmoscope. setting up (2). pts right eye. which hand and eye for you (2).
• first view anterior segement and red reflex. starting position (2) should see (1). what does anterior segment include (5)
• second view fundus. move close and focus. what to look for and how (4)

Answer 6

• ask pt to fix on an object straight ahead
• ask pt to remove glasses if they have them. remove yours too unless very blind
• using opthalmoscope >dim lights, large round beam. pts right eye. your right hand and eye. hold against your brow. steady pts head. pt sits you stand.
• anterior segment and red reflex. start 30cm and 15 degrees temporal from their front line of vision. should see red reflex. focus dial -start at 10 and go down until focussed. anterior segment includes everything anterior from and including lens - conjunctivia, cornea, anterior chamber, iris, lens.
• fundus

> optic discpt looks straigh ahead, nasal and slightly above horizontal meridian

• >*retinal blood vessels follow out of optic nerve
• >*macular region ask pt to look directly into light. located in temporal half of fundus.

>general fundus and peripheral fundus backgrounds. move about systematically. for periphery ask pt to look up down left right. may need to refocus.

Question 7

• how to say normal
• anterior segement and red reflex. what signs may you see here.
• examining disc. what to observe (4)
• observe vessels
• observe macular region. what will it look like (2)
• observing fundus background. what will it look like in lightly pigmented pt (1). and in heavily pigmented pt (1)

Answer 7

• NAD/ no abnormalities detected
• when examining ant segment and red reflex may see subtle opacities or defects in optical media against background of red reflex.
• when examining optic nerve should observe - clarity of margins, colour, nature of central cup, vessel entry, presence or absence of haemorrhages
• observe vessels
• macular region will look like a dot. closer examination may show a yellowish colour
• fundus background. in lightly pigmented pt will be able to see through stippled pigment epithelium and obtain a view of the choroid vasculature. in heavily pigmented pt fundus will be uniformly black.