Eye Assessment Flashcards
What do the six muscles that attach to the eye do?
They serve to direct eye to points of the person’s interest.
What kind of movements do the muscles that attach to the eye provide?
Straight and rotary
Describe the sclera of the eye.
Tough, protective white coat that is continuous with transparent cornea which covers the iris and pupil.
What is the cornea?
Is a part of the refraction of the eye which bends incoming rays.
Describe the cornea.
- Sensitive to touch
- Cotton ball causes blink reflex called ‘corneal reflex’.
- Innervation by Trigeminal Cranial Nerve (CN V), by afferent sensation to brain (Discuss afferent and efferent).
- Facial Cranial Nerve (CN Vll) carries efferent message and actually causes the ‘blink reflex’.
What is the choroid?
Is dark pigmentation which prevents light from reflecting internally.
What is fixation?
Ability of center of eye to track an object
What is accommodation?
- Adaptation of the eye for near vision
- Increase curvature of lens
- Observe when pupils converge and constrict
Infant and Children Vision
- Peripheral vision intact, central vision clear by 3-4 months
- Will start tracking
- Eyeball reaches adult size by age 8
- Light iris and small pupil at birth
What are problems older adults can face with vision?
- Presybyopia
- Loss of structural tissue, elasticity
- Involution of lacrimal glands:
- Debris in vitreous: floaters
What is presybyopia?
- Loss of flexibility in lens
- Loss of accommodation/near vision
- Difficulty reading
What does loss of structural tissue cause?
Sunken eyes
What does involution of lacrimal glands cause?
Less tear production
What are the guidelines for eye care?
- Every 10 years until 40
- Every 5 years to 55
- Every 3 years to 65
- Every 2 older than 65, diabetes, or eye disease
Subjective Data:
- Vision difficulties (, color changes, floaters, blurring, blind spots)
- Eye pain
- Strabismus (crossed eyes)
- Diplopia (double vision)
- Redness, swelling
- Watering, discharge
- History of ocular problems
- Glaucoma
- Use of glasses/contacts
- Self-care-testing, environmental exposure, safety
Inspect External Ocular Structures: General, eyebrows, eyelids and lashes, and eyeballs
-General: groping, squinting, struggling to see
Eyebrows: bilateral, move symmetrically, no scaling or lesions
Eyelids and lashes: approximate, no swelling, redness, discharge, lesions
Eyeballs
Aligned, not sunken or protruding
Assessment of Conjunctiva and Sclera
- Pink conjunctiva, white sclera
- Moist, glossy eyeball
- No drainage, lesions, color changes
inspection of Lacrimal Apparatus
- Patient looks down
- Slide outer part of upper eyelid up along bony ridge with your thumbs
- Inspect for redness, swelling
- Press index finger gently along lacrimal sac (not nose)
- Redness, fluid indicates swelling
Assessment of the Cornea and lens
- Shine light from the side across the patients cornea
- No cloudiness or irregularities in cornea, anterior chamber or lens
Hoe do you assess the Iris and pupils?
- Iris has regular shape, uniformity
- Pupils equal in size (3-5 mm)
Check pupillary light reflex
- Darken room
- Request patient to look into distance
- Advance the light from the SIDE about 4-6” from eye
- Check same side (direct response)
- Check opposite eye (indirect response)
- Repeat for other eye
How do you assess accommodation?
- Patient focuses on distant object (dilates pupil)
- Shift gaze to near object (finger 7-8cm from nose)
- Pupils should constrict and converge
What does PERRLA stand for?
Pupils equal, round, reactive to light, accommodating
What tests can be used to assess Extraoccular Muscle Function?
- Corneal light reflex
- Cover-uncover test
- Diagnostic positions test
How do you perform a corneal light reflex test?
- Examiner 30 cm away
- Patient staring straight ahead
- Shine light on cornea
- Should be in exact same spot
- Asymmetry indicates muscle weakness or paralysis
How do you perform the cover-uncover test?
- Patient to stare at your nose
- Cover one eye with opaque card
- Uncovered eye should remain steady
- Remove cover and watch –if muscle weakness exists the covered eye will have drifted away and you will see it come back to center
Eye muscle function : 6 cardinal positions
- Patient tracks your fingers through all 6 cardinal directions
- Finger about 30 cm away
- No head movement, only eye movement
- Both eyes should move together through all six directions
- Follow clockwise procedure
- Evaluates cranial nerves and muscle function
What does confrontation measure?
Peripheral vision
How do you assess confrontation?
-Compared with the testers vision, eye level, 60 cm apart
-Patient covers one with card, looks directly at you with other eye
-Tester covers same eye
-Testing the uncovered eye bring stimulus in from peripheral field
-Patient states “now” when they see the stimulus
s
Visual Acuity: Snellen
-Patient at 20 ft from chart
-Glasses/contacts on (not reading glasses)
-Cover one eye with card
-Top to bottom, left to right
-Record last line successfully read
Eg. L eye 20/40 -1
Visual acuity: Written
- Test in those over 40 or reporting difficulties reading
- Card at 14 inches
- Test each eye separately and with glasses
Newborn (infant): visual development
Newborns
- Test visual reflexes and attending behaviors
- Blink with exposure to bright light
- Check pupil response
- 2-4 wks fixates on objects
- 3-4 months –follows and reaches for toy
Visual acuity testable at 42 months
- Snellen E chart
- Corneal light reflex at 6 mos
Children: visual development
- Visual acuity every 2 years
- Visual fields when able to hold head still, follow directions
Colour blindness (inherited in about 8% of males with european descent) -Test boys once age 4-8 years
Check for strabismus
- Corneal light reflex
- Cover-uncover test
