Accommodation
Adaptation of the Eye for near vision. It is accomplished by increasing the curvature of the lens. Test for accommodation by asking the person to focus on a distant object. This process dilates the pupils. Then have person shift gaze to a near object, suc
Arcus senilis:
commonly seen in cornea. This is a gray-white arc or circle around the limbus; it is due to deposition of lipid material. As more lipid accumulates, the cornea may look thickened and raised, but the arcus has no effect on vision.
Blepharitis
Inflammation of the eyelid. Red, scaly, greasy flakes and thickened, crusted lid margins occur w/ staph, seborrheic dermatitis on lid edge.
Cataract
Lens opacity, resulting from clumping of proteins in the lens. Some formation should be expected by 70 yrs. 46% of people between 75-85 yrs have cataracts. (senile cataracts)
Central Vision
Testing cranial nerve ii (optic)
vision using the fovea and parafovea; the middle part of the visual field
Tested with/ the Snellen eye chart (far vision), Hand health vision screener (near vision
Peripheral Vision
Testing visual fields, the confrontation test.
Tested by having person cover one eye while examiner does the same, then say now the first moment they see the object.
Have the person look at you, as a midpoint reference. They should be able to see it the f
Night Blindness
occurs with optic atrophy, glaucoma, or Vit. A deficiency.
Nystagmus:
involuntary eye movement. Occasionally associated with vertigo. It's best seen around the iris. It is only normal at an extreme lateral gaze.
Periorbital Edema
Lids are swollen and puffy. Lid tissues are loosely connected so excess fluid is easily apparent. This occurs with local infections; crying; and systemic conditions such as congestive heart failure, renal failure, allergy, hypothyroidism (myxedema)
Photophobia
the inability to tolerate light. Some common eye diseases (cataract, glaucoma)
Convergence
In ophthalmology, convergence is the simultaneous inward movement of both eyes toward each other, usually in an effort to maintain single binocular vision when viewing an object. This is the only eye movement that is not conjugate, but instead adducts the
Presbyopia
Decreased ability of the lens to change shape to accomodate for near vision. By 40 yrs. 50% of people have this, by 70 yrs the transparent fibers start ot thicken and yellow (senile cataract). This can be diagnosed when the card is moved further away.
Corneal Light Reflex (Hirschberg Test)
Shine the penlight about 30 cm away from person. The bright white dots should shine in the same spots in each eye. For symmetry of the corneal light reflex. (Deviation-indicates weakness of paralysis of eye muscles; perform the cover test to diagnose it.)
Ptosis
Drooping of the eyelids. Can't lift it, normally nerve damage. (typically permanent)
Diplopia
Double vision: two images of a single object.
Pupillary Light Reflex (direct, consensual)
Direct: When one eye is exposed to bright light and constriction of that pupil
Consensual: Simultaneous constriction of the other pupil. This happens bc the optic nerve carries the sensory afferent message in and then synapses on both sides.
Glaucoma
Increased intraocular pressure. Leading cause of blindness in US. Risk increases with age. No cure, may meds and treatments. Many forms-Open angle and closed angle.
Risk factors: Age over 60, A.A. heritage, increased ocular pressure, steroid use, family h
Strabismus
Cross Eyed-eyes don't look toward an object together. Deviation of the axis of the eyes. Testing for it-during early childhood. Tested by corneal light reflex or cover test. Untreated strabismus can lead to permanent visual damage. Early recognition is ke
Hordeolum
sty or stye (infection of eyelash follicle
Visual Acuity
tested with snellen eye chart and handheld vision screener. which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain-cranial nerve ii
Hyperopia
Far Sightedness-difficulty focusing on close objects (increases w/ age-presbyopia) Light enters the eye and focuses behind retina instead of directly on it.
Myopia:
Nearsightedness-difficulty seeing distant objects. Light rays of image focus in front of retina rather than directly on the retina.
Handheld visual screener
Visual Fields
Test visual fields-confrontation test, test by gross confrontation. tests peripheral vision.
4. Explain the statement "Normal visual acuity is 20/20. What does 20/20 mean (numerator, denominator)?
Normal visual acuity: 20/20. the top number (numerator) is the distance the person is standing from the chart. Denominator: gives the distance at which the normal eye could read that particular line "20/30" means "you can read at 30 feet what the normal e
6. What Snellen chart result would you recommend that a patient see an ophthalmologist or optometrist?
Poorer than 20/30
8. Explain how to assess for extraocular muscle function: (a) corneal light reflex test (Hirschberg Test); (b) Cover test; (c) Diagnostic Positions Test (Six Cardinal Fields of Gaze). Explain the reason for assessing extraocular muscles function and expla
Six Muscles: attach the eyeball to its orbit and serve to direct the eye to points of the person's interest. They give the eye both straight and rotary movement. The 4 straight or rectus muscles are the superior, inferior, lateral, and medial rectus muscl
Corneal light reflex (Hirschberg test)-
person stare straight ahead as you hold 3 cm away.
Cover (Cover-uncover test)
Note uncovered eye
Positions test (diagnostic) or EOMs:
six cardinal fields of gaze. tests that muscles that move the eye. Lead the eye through 6 cardinal positions of gaze. Cranial nerves tested: iii, iv, vi oculomotor, trochlear, abducens.
9. What are the normal findings when inspecting the external ocular structures (e.g. general, eyebrows, eyelids, eyelashes, eyeballs, conjunctiva, sclera, lacrimal apparatus, cornea, lens, iris, and pupil). What are the normal variations of persons with d
General: ability to move around room and see facial expression
Eyebrows: equal, bilateral, move symmetrically
Eyelids/eyelashes: intact skin, eyelashes evenly distributed. In Asians slight upward slant of palpebral fissures.
Eyeballs. No protrusion or sun
Testing pupillary light reflex:
Darken room ask person to look off into distance. This DILATES the eyes. Advance a light from the side: this CONSTRICTS the eyes. Normally you'll see constriction of same-sided pupil (direct light reflex) and simultaneous constriction of the other (consen
what does PERRLA mean?
Pupils equal, round, reactive to light and accomodation.
When assessing with the ophthalmoscope, what part of the eye is being examined?
Inspects inner structures of eye such as the retina, macula (central vision)
Use of the opthalmoscope:
Its important to get prospective, To see, retinal vessels, and the red reflex. I.E. diabetic retinopathy
Describe the red reflex and its significance.
Reflection of your opthalmoscope light off the inner retina. Inspects structures 1) optic disk 2) retinal vessels 3) general background 4) macula.
12. What cranial nerves are being tested when assessing the eyes? What tests are used and what are the normal findings?
ii, iii, iv, vi, oculomotor, trochlear, and abducens
13. Explain some of the common causes of decreased visual function in the older adult
Lacrimal apparatus decreases tear production. Arcus senilis: cloudy cornea circle or arc. It has no effect on vision though. Pupils are smaller and slower pupillary light reflex. Retinal structures have less shine.
Describe the developmental changes related to the eyes (infants and children
2-4 wks: eyes can fixate on an object
1 mnth: can follow a light or bright toy
3-4 months: infants can fixate, follow, and reach for the toy
6-10 months: infants can fixate and follow toys in all directions.
Test for strabismus in first 6 years.
Review "Promoting a Healthy Lifestyle: Screening for Glaucoma" (including what is glaucoma, risk factors, most common type of glaucoma, when glaucoma testing should be started and the frequency of testing
Involves optic nerve damage. Glaucoma, most fall into two categories: open-angle (more common) and closed-angle, the drainage canals of the eye gradually become clogged.
Testing starts at 29 yrs. of age.