The Eye Exam Flashcards
7 Elements of Patient History
- Demographic
- Chief Complaint
- History of Present Illness
- Review of Systems
- Social history
- current medications
- Allergy to medications
Visual Acuity
Measure of the finest detail the eye can detect
Snellen Letters
The eye chart used to test distance vision
Snellen refraction
Testing distance– Distance at which letter is standardized to be read
What does 20/40 mean?
At 20 feet, the person read what is standardized to be read at 40 feet
What does cover/uncover testing do?
Examines binocular relationship of the eyes (how well eyes are working together)
Esotropia
Eye deviating inward
Exotropia
Eye deviating outward
Hypertropia
Eye deviating upward
What happens if you put an occulder over the fixated eye? *the good eye
The deviated eye will quickly refixate
Keratometry
Opthalmometry
Keratometry
Measures curvature of the cornea and focusing power of cornea
Benefits of keratometry
Doesn’t require patient responses
What keratometry can do?
estimate focusing power of cornea, amount of astigmatism, evaluate integrity of surface of eye, estimate base curve of lens during contact lens fitting
Benefits of Automated Keratometers
Quicker to get K-Reading, little training to use, automated refraction (if build in to machine)
Topography
Measures thousands of points along cornea to provide curvature, refractive power, and radius of cornea
Benefit of topography
measures wide area and many points of measurement (keratometer only measures 4 points)
What is corneal topography used for?
To screen before refractive surgery, fitting contacts, adjusting post surgical corneal transplants, diagnosing refractive disorders/diseases
What is Retinoscopy?
Objective measure of refractive power of the eye
Retinoscope
Hand-held instrument used to measure retinoscopy
How does retinoscope work?
Bright light shined in patients eye, doctor examines the reflex of the pupil and then places lenses in front of eye to determine prescription
What is objective when using retinoscope?
To find a lens that stops the reflex of pupil
“With” movement
Add plus powered lenses
“against movement”
minus powered lenses
Ocular Adnexa
All adjacent structures of the eyes (eyelids, lashes, eyebrows, lacrimal apparatus, tarsal plates, orbit, muscles, conjunctiva
Manifest/Subjective Refraction
Using patient responses to determine refraction (prescription)
What instrument is used for a subjective refraction?
Phoropter
What is opthalmoscopy?
Examination of the inside of the eye
What tool is used for opthalmoscopy and how does it work?
An opthalmoscope– illuminates and inspects interior of the eye
Two types of opthalmoscopes?
direct and binocular indirect
Direct ophthalmoscope
Hand held and yields a larger image but smaller field of view
Binocular direct opthalamoscope
Worn on the head, uses hand held lens- yields smaller image and much larger field of view– need dilation drops to get better internal view
What is purpose of opthalmoscopy?
To detect diseases and abnormalities in internal part of eye
What is binocular vision?
Eyes working together as a team
What is tonometry?
Test to measure intraocular pressure in the eyes
What does tonometry help diagnose?
Glaucoma
Non Contact Tonometer (NCT)
puff test for checking IOP
Goldmann Tonometer
Mounted to slit lamp, requires aenestic drop because probe touches cornea
Tono-pen
hand held tonometer but stil requires anesthetic drop to get a reading
Visual field
Area of space that is visible to the eye
Perimetry
Test to measure visual field
Confrontation fields
manual visual field test
Humphrey, Dicon, Octupus
Automated visual field test
Biomicroscopy
Slip- lamp examination to get highly magnified view of structures of the eye
Usues of biomicroscope?
Observe contact lens fit, check for foreign bodies, look at all parts of front of the eye to check for health
Can you view back of the eye with biomicroscope?
Yes, but need special lenses
What is fundus?
bottom or base of anything (in medicine– inner lining of hollow organ)
Ocular fundus
Inner lining of eye (sensory retina and retinal pigment epithelium, brushs membrane, choroid)
Fundus photo
taking pic of back of eye to check eye helath-
What does fundus photo see?
Optic nerve, vitreous, macula, retina, and blood vessels
How does fundus photo work?
visualize back of eye by focusing light through the cornea, pupil, and lens
Posterior pole
Retina between optic nerve and macular area
Arcades
Normal pattern of retinal blood vessels
Cup-to-disc ratio
Percentage of disc occupied by optic cup
Exudates
Proteins/fatty fluid that leads from blood vessels into retinal tissue
Cotton wool spots
fluffy looking white deposits within retinal nerve fiber layer– small patches of retina that have lost their blood supply from vessel obstruction
Nevus
A mole on the eye
Pachymetry/Pachymeter
Measures thickness of cornea– determines if cornea is strong enough for surgery and monitors diseases that thicken cornea
Lensometer
Instrument used to measure prescription on glasses and contact lenses
Asepsis
practice of reducing contaminants to prevent infection
Accomodation
Eyes ability to focus objects from distance to near– the cyrstalline lens changing shape to refract light
Emmetropia
Image focuses on back of retina when accomodation is relaxed– no correction required
Ametropia
image is focused somewhere other than retina– requires correction
Myopia
When accommodation is relaxed, images are focuses in front of the retina resulting in blurry distance vision
Causes of myopia
Eye is too long
How is myopia corrected?
With minus lenses
Hyperopia
Farisightness, image focuses behind retina
Causes of hyperorpia
Cornea too flat or eyeball to short – needs plus power
Astigmatism
When is relaxed state, image is focused at two points
Cause of astigmatism
Cornea is longer at one meridian than the other
Presbyopia
Loss of ability to see up close (usually in old people)
Cause of presbyopia
Lens cant change shape (accommodate)
Vertex distance
distance from where the back of the spectacle lens rests in front of the eye to where the contact lens rest on the eye
Is lens thinner or thicker in the center for hyperopia?
Thicker