VISION, HEARING, & VESTIBULAR:
- clouding of the eye interferes with transmission of light of retina - bilateral - age common cause - risk factors; sunlight ultraviolet radiation, diabetes, trauma, drugs (corticosteroids) - manifestations; > blurred vision/visual distortion > decreased visual acuity > glare > decreased color perception
cataracts
(occurs from dysfunction of the vestibular apparatus in the brainstem)
central vestibular disorder
coordination of eye control, head movement, & posture
cerebellum
influence muscle tone and postural adjustment
spinal cord
The nurse documents the presence of nystagmus when assessing a client. This can be interpreted as: a)Voluntary eye movements that preserve eye fixation on stable objects in the visual field b)Involuntary eye movements that preserve eye fixation on stable objects in the visual field c)Fixed eye movements that preserve eye fixation on unstable objects in the visual field d)Unilateral eye movement that preserve eye fixation on unstable objects in the visual field
ANSWER: (B) Nystagmus refers to the involuntary eye movements that preserve eye fixation on stable objects in the visual field during angular and rotational movements of the head. As the body rotates, the vestibular-ocular reflexes cause a slow compensatory drifting of eye movement in the opposite direction, thus stabilizing the binocular fixation point.
What is the best menu selection for a client prescribed a low sodium diet for Ménière's disease? a)Seafood stir-fry with fried rice b)Baked chicken with steamed broccoli c)Canned spaghetti with garlic bread d)Salami sandwich on rye bread with pickle
ANSWER: (B) A low sodium diet helps to minimize fluid retention and has been recommended for treatment of Ménière's disease. Foods high in sodium include many processed foods such as TV dinners, salty snacks, cheeses, cured meats, seafood, broths, gravy, salad dressings, pickles, and soy sauce.
Amblyopia, or lazy eye, occurs at a time when visual deprivation or abnormal binocular interactions occur in visual infancy. Whether amblyopia is reversible depends on what a)The child has to be older than 5 years b)The child has to have bilateral congenital cataracts c)The child has to be able to wear contact lenses d)Maturity of the visual system at time of onset
ANSWER: (D) The reversibility of amblyopia depends on the maturity of the visual system at the time of onset and the duration of the abnormal experience. The other answers are incorrect.
one phase of the eye movement is faster than the other
Jerk nystagmus
- degeneration (worsening) changes in the central portion of the retina - loss of central vision - common cause; age - genetic predisposition - risk factors; > hypertension > cigarette smoking > diabetes mellitus > family history - other causes; > deterioration of the central portion of the retina, the inside back layer of the eye that records the images we see and sends them via the optic nerve from the eye to the brain, cigarette smoking, obesity, lack of dietary nutrient - incurable eye disease
age related macular degeneration: (AMD)
- bilateral - tearing, itching, and hyperemia of the eyes - occurs due to small airborne allergens; pollens - treated with eye washes or meds
allergic conjuntivitis
- when the vision in one of the eyes is reduced because the eye and the brain are not working together properly - eye itself looks normal, but it is not being used normally because the brain is favoring the other eye - eye and the brain are not resulting from abnormal visual development in infancy or early childhood - common cause of monocular visual impairment; one eye is not working - responsive to early treatment; before the age of 6 can recover - put patch on good eye to make the bad eye work harder to develop properly; when developed take eye patch off or glasses off
amblyopia "lazy eye"
- can be unilateral or lateral - large amount of yellow green drainage - eyelids are sticky and tender - can be transmitted from mom to newborn during delivery
bacterial conjunctivitis
- stimuli is not conducted to the middle ear; impacted ear wax, otits externa... - occurs when a change in outer or middle ear impairs conduction of sound from outer to inner ear. - conditions that cause it; > impacted cerumen > benign tumors of the middle ear > carcinoma of the external auditory canal or middle ear > eustachian tube dysfunction > otitis media > cholesteatoma (accumulation of keratinized epithelium) > otosclerosis
conductive hearing loss
- rare; individual does not respond to voice and appears not to hear - caused: emotional or psychologic factors
functional hearing loss
- increased intraocular pressure in the eye - imbalance between the aqueous humor production and drainage - elevated pressure will damage the optic nerve and impair vision - damage the eye's optic nerve and can result in vision loss and blindness. - leading cause of blindness for people over 60 years old. - blindness can be prevented with early treatment
glaucoma
-Disorder of the inner ear -Triad of Manifestations... >Hearing loss >Vertigo >Tinnitus - Fluctuating episodes of symptoms occurs > Can be so severe as to lead to inability to sit or walk - Possible causes... abnormality in the structure and/or the amount of fluid in the inner ear . > Infection, trauma, endocrine, vascular ... > High sodium diet causing fluid increase in ear
meniere's disease:
- includes both conductive and sensorineural loss - with functional hearing loss; rare, individual does not respond to voice and appears not to hear > caused: emotional or psychologic factors
mixed hearing loss
- involuntary unilateral or bilateral rhythmic eye movement - pendular nystagmus; regular back and forth movement - Jerk nystagmus; one phase of the eye movement is faster than the other
nystagmus
steadies the eyes as the head and body moves
oculomotor nuclex
regular back and forth movement
pendular nystagmus
occurs because of dysfunction of the vestibular apparatus in the inner ear
peripheral vestibular disorder
most common form of sensorineural hearing loss in elderly - cause: atrophy of the basal end of organ of corti, loss of auditory receptors, changes in vascularity , or stiffening of the basilar membranes.
presbycusis
- central portion known as the macula, - is responsible responsible for focusing central vision in the eye, - it controls our ability to read, drive a car, recognize faces or colors, and see objects in fine detail.
retina
- Stimuli Is conducted to the middle ear...BUT the inner ear structures (cochlear apparatus or auditory nerves) prevent conduction of sensory messages to the brain; Ototoxic drugs, Noise, head injury... - cause: impairment of the organ corti or its central connections. - hearing loss gradual or suddenly - conditions causing it: > congenital or hereditary factors > noise exposure > aging > meniere disease > ototoxicity > systemic disease (syphilis, paget disease, collagen diseases, diabetes mellitus), neoplasms, and autoimmune processes.
sensorineural hearing loss
- misalignment of the eyes - eye can turn un various directions - occurs in children can also occur in adults - which a person can not align both eyes simultaneously under normal conditions. - cranial nerves (III, IV, VI); responsible for eye movement; if weakness or paralysis of muscle; strabismus occurs - if not treated early can have permanent or secondary loss of vision or amblyopia - An eye turn may be constant (when the eye turns all of the time) or - intermittent (turning only some of the time). - One or both of the eyes may turn in, out, up or down. - person can not align both eyes simultaneously under normal conditions.
strabismus
interprets input, plays a role in motion perception & spatial orientation
thalamus & cortex
(T/F): Amblyopia is the medical term used when the vision in one of the eyes is reduced because the eye and the brain are not working together properly. The eye itself looks normal, but it is not being used normally because the brain is favoring the other eye
true
- an illusion of motion occurs - person stationary but senses the environment is in motion - motion sickness is a form of physiologic vertigo - can occur due to a central or peripheral vestibular disorder; <central > (occurs from dysfunction of the vestibular apparatus in the brainstem) <peripheral > (occurs because of dysfunction of the vestibular apparatus in the inner ear)
vertigo
- is the sensory system that provides the leading contribution to the sense of balance and spatial orientation for the purpose of coordinating movement with balance. 0. movement 1. receptors in the inner ear 2. brainstem 3. thalamus & cortex, oculomotor nuclex, spinal cord, cerebellum
vestibular system
- unilateral or bilateral - highly contagious - spreads through direct contact - hyperemia, copious (large amount) tearing, minimal exudate of the eyes - children more at risk - do not share personal things
viral conjuntivitis (Adeno)