visual & sensory Flashcards
define cataracts
cloudy lens.
gradual onset of painless blurry vision.
if left untreated, may end in blindness.
cataracts: risk factors
Older age
Eye trauma
Congenital risk
Diabetes
Corticosteroid use
Smoking and ETOH consumption
Cataract manifestations
Painless
Uni- or bilateral vision changes
Blurry
Halo around lights
Altered color perceptions
Glare issues at night
Decreased accommodation
treatment of cataracts
surgery
Diabetic retinopathy: nonproliferative retinopathy
Capillary microaneurysms, retinal swelling, hard exudate
Macular edema- plasma leaks from macular blood vessels
Capillaries rupture, leading to “dot or blot” hemorrhaging
Diabetic retinopathy: proliferative retinopathy
Advanced retinopathy
New blood vessels are fragile and leaky
hypertensive retinopathy
Etiology: high BP creates blockages in retinal blood vessels.
Initially there no vision changes
Sustained, severe HTN can cause sudden visual loss related swelling of the optic disc and nerve.
Normal vision is restore with treatment of the HTN
define detached retina
Retina has a tear or leak.
Vitreous humor flows behind the retina.
Rapid, progressive detachment from the choroid.
Usually spontaneous.
who is most likely to have a detached retina?
people who have myopia.
Over 40.
Traumas to the head: Eye tumors, Complication or history of cataract surgery
Clinical manifestations of detached retina
SUDDEN, unilateral vision loss
Painless
May see floaters
Flashes of light
myopia
nearsightedness
cant see far away
Age related macular degeneration
Most common cause of irreversible vision loss in people over 60 in the US
2 types of Age related macular degeneration
Dry (non-exudative)- most common, 90% of cases
Wet (exudative)- only 10%
etiology of Age related macular degeneration
retinal aging
risk factors of Age related macular degeneration
Family history, genetics, UV light, hyperopia, smoking, light-colored eyes
what food is protective for age related macular degeneration
Dark green, leafy vegetables
Dry macular degeneration
Yellow deposits in the retinal pigment epithelium
wet macular degeneration
Growth of new, leaky blood vessels in an abnormal location of the retina
manifestations & treatment for age related macular degeneration
Early on– usually no symptoms
Later: Blurred, darkened vision, Blind spots (scotomas), Distorted vision (metamorphopsia).
Vision does not improve, treatment is limited, Medications are injected into the eye.
glaucoma
Elevated intraocular pressure (IOP) PLUS + Vision changes OR optic nerve damage.
Chronic condition
Usually bilateral eye involvement
what are the 2 types of glaucoma?
Open-angle
Closed-angle
Risk factors of Open-Angle Glaucoma
Elevated IOP
Age- older
Race: African-Americans 3-4x higher risk
Family history
Myopia
Diabetes, HTN, migraines
hyperopia
farsightedness
inability to see close objects
Open-angle glaucoma pathogenesis
Abnormal trabecular meshwork.
Reduced drainage of aqueous humor into canal of Schlemm.
Imbalance between inflow and outflow.
Results in increased IOP and vision problems.
Open-angle glaucoma: clinical manifestations
None usually
Progressive loss of sight
Vague eye pain
Halos around lights
Tunnel vision
Closed-angle glaucoma
Much less common
Abnormal angle between the iris and later cornea
Outflow is blocked when the pupil is DILATED
closed angle glaucoma is also known as:
Acute angle-closure glaucoma (AACG)
Narrow-angle glaucoma
closed angle glaucoma: risk factors
Asian American ethnicity
Females
Hyperopia
Family history
Older age
is Acute angle-closure glaucoma an emergency?
YES!!
Outcome based on time from onset to treatment
What triggers an acute episode of closed angle glaucoma?
anticholinergic drugs
Acute closed-angle glaucoma: clinical manifestations
Typically UNILATERAL:Other eye is at risk
SEVERE eye pain
Nausea and vomiting
Blurry vision, halos
Reddened eyes
Dilated pupil– non-reactive to light
Cloudy cornea
Glaucoma and blindness
d/t the increased IOP
More pressure on inner eye structures
Decreased blood flow to optic nerve
Nerve fiber death leads to blindness
which drugs decrease AH production
timolol
betaxolol
brimonidine
which drug increases AH drainage
latanoprost
timolol- nonselective & betaxolol- B1 receptor blocks
Class: Optic-topical beta-blockers
MOA: Block SNS stimulation of beta receptors
SE: Transient burning & discomfort, If allowed to go systemic- can have systemic effects
Contraindications: Same as oral beta-blockers
Therapeutic use: Open-angle glaucoma maintenance treatment, If acute-angle closure– need drops asap and other interventions
Patient teaching: Must take– otherwise will progress to blindness, Apply nasolacrimal pressure with instillation.
latanoprost
class: Prostaglandin analogs
MOA: increases outflow drainage of aqueous humor
Indications: Open-angle glaucoma, Ocular hypertension
SE: well-tolerated
brimonidine
class: Alpha-adrenergic agonist
MOA: decreases AH production, may increase drainage/outflow
Indication: Used for open-angle glaucoma & increased IOP
SE: Burning/stinging, Dry mouth, Fatigue, H/A, blurred vision, hypotension
dozolamide
class: Carbonic anhydrase inhibitor
MOA: decreased production of aqueous humor
SE: Stinging, Bitter taste, Allergic reactions (conjunctiva or lid reactions)
Second-line treatment: Open-angle and increased IOP
meniere disease
Endolymphatic hydrops
Episodic disorder of the middle ear
Can be unilateral or bilateral
Excessive endolymph and pressures in the membranes disrupt vestibular (balance) and hearing function
CM & treatment of Meniere Disease
recurring episodes of vertigo [usually with nausea & vomiting], hearing loss, ringing in the ears (tinnitus), and feeling of fullness
Treatment is symptomatic
