Term
Direct opthalmoscopy
pg 2048 |
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Definition
| hand-held instrument w/ various +/- lenses that can be adjusted to bring conea, lens, and retina into focuas sequentially; examiner uses rt hand and eye for pt's rt eye, left for left; room should be dark; examiner eye level w/ pt's eye, pt given target to look at and encouraged to keep both eyes open and steady; used to detect microaneurysms, drusen, hemorrhages, and lesions |
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Term
Indirect opthalmoscopy
pg 2049 |
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Definition
| commonly used to see lg areas of retina; no magnification; bright and intense light; light source is attached to binocular lenses mounted on examiner's head; used w/ a hand-held 20 diopter lens |
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Term
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Definition
| binocular microscope mounted on table; magnifies 10-40x; illumination can be varied from broad to narrow beam for different parts of eye; looks for inflammation, cataracts; when used w/ 3-mirror lens, may examine the angle of the anterior chamber and ocular fundus |
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Term
Color Vision Testing
pg 2049 |
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Definition
| cones are responsible for color vision; greatest concentration is in macula; Isihara Polychromatic Plates (booklet); dots of primary colors integrated into a background of secondary colors; arragned in simple patterns and pts asked to identify; central vision conditions most commonly color-blind |
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Term
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Definition
| used for macular problems; geometric grid of identical squares w/ a central fixation point; viewed by pt w/ normal reading glasses; each eye separately; stare @ fixation point and report distortion in squares; lines may look faded or wavy; older pts may be given gris to take home to check vision regularly |
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Term
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Definition
| especially useful if retina is obscured by cataract or hemorrhage; looks for tumors, lesions, retinal detachment; changes in tissue composition; 3D images can be created for future comparison |
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Term
Fluorescin Angiography
pg 2049 |
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Definition
| evaluates clinically significant macular edema, macular capillary nonperfusion, retinal and choroidal neovascularization; invasive; fluorescin dye injected, takes 10-15 secs to spread, pics of vasculature are taken over a 10 min. period; dye may give skin a gold tone and turn urine a deep yellow or orange; usually goes away w/in 24 hours |
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Term
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Definition
| measures IOP by determining amount of pressure necessary to indent or flatten (applanate) a small anterior area of the globe of the eye (mm Hg); increased reading indicates increased pressure; noninvasive, usually painless; anesthetic eyedrop used; performed w/ an Applanation Tonometer (more skilled examiner) or Tono-Pen |
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Term
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Definition
| evaluates field of vision; avg= 65 degrees up, 75 down, 60 in, 95 out; most helpful in detecting central scotomas; 2 methods, automated and manual; manual uses moving and stationary targets; automated uses only stationary targets (harder and more accurate) |
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Term
Open Angle Glaucoma
pg 2056 |
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Definition
| usually bilateral, one eye may be more severely affected; anterior chamber angle is open and appears normal |
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Term
Closed Angle Glaucoma
pg 2056 |
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Definition
| obstruction in aqueous humor outflow d/t complete or partial closure of angle from forward shift of peripheral iris to trabecula; obstruction results in increased IOP |
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Term
Retinal Detachment
pg 2067 |
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Definition
| separation of RPE from sensory layer; 4 types- rhegmatogenous (most common), traction, combo of rhegmatogenous and traction, and exudative; S/Sx: sensation of shade or curtain across one eye, cobwebs, bright flashing lights, sudden onset of great # of floaters, no pain; Dx:dilated fundus exam (indirect opthalmoscope, slit lamp), stereo fundus photography, fluorescin angiography, ultrasound, optical coherence tomography |
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Term
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Definition
| shortened or elongated eyeball prevents light rays from focusing sharply on the retina; blurred vision can be corrected w/ lenses; myopia-nearsighted, hyperopia-farsighted, astigmatism-irregular curve of cornea |
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Term
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Definition
| general term describing visual impairment that requires devices and strategies in addition to corrective lenses; BCVA 20/70- 20/200 |
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Term
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Definition
| BCVA 20/400 to no light perception |
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Term
Risks for low vision and blindness
pg 2051 |
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Definition
| pts over 40 y/o, diabetic neuropathy, macular degeneration, glaucoma, cataracts; macular degeneration is more common in Caucasians, Glaucoma in African Americans |
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Term
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Definition
| examiner covers untested ear w/ palm, whispers softly 1-2 ft from unoccluded ear and out of pts sight; pt w/ normal acuity can repeat what was whispered |
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Term
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Definition
| uses bone conduction to test lateralization of sound; tuning fork, usually 512 Hz, set in motion and placed on pt's head or forehead; normal-hears sound equally in both ears or centered in head; conductive hearing loss- hears better in affected ear; sensorineural hearing loss- hears better in good ear; this test is good for detecting unilateral hearing loss |
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Term
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Definition
| examiner shifts tuningfork from 2 in from opening of ear canal to against mastoid bone; pt is asked to indicate which is louder or when the sound is no longer heard; used to distinguish between conductive and sensorineural loss; normal results= air conducted is louder than bone conduction |
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Term
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Definition
| infection of mastoid bone; S/Sx: ear pain or discomfort, swelling behind ear ( may cause ear to stick out), redness of ear or behind ear, fever, HA, drainage from ear; Dx: examination of head, skull x-ray, CT scan, culture of drainage may show bacteria |
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Term
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Definition
| abnormal bone growth in middle ear that causes hearing loss; inherited; most frequent cause of middle ear hearing loss in young adults; most common in women 15-30; S/Sx: hearing loss, slow progressive loss, hearing may be better in noisy environments; tinnitus; Dx: hearing test (audiometry, audiology), temporal bone CT can distinguish between otosclerosis and other causes |
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