PATHO CH46 - Alteration in Special Sensory Function

strabismus (cross-eyedness)

• squint/cross-eyedness

• condition of ocular misalignment

cause of strabismus

abnormal “set: of the fusion mechanism of the visual system

treatment of strabismus

• occlusion therapy or eye patching

• path good eye to force it to work)

• corrective lenses

• surgery or eye exercising

amblyopia (lazy eye)

• poor vision of one or both eyes despite proper optical correction

• altered visual development despite normal appearing retinal & optic nerve pathways

amblyopia leads to decreased

visual acuitary

treatment of amblyopia

• atropine / anticholinergic

• patching of the stronger eye

contraction of the pupil (PSN)

miosis

cataracts

• clouding or opacity of lens

• leads to gradual, painless blurred vision & eventually loss of sight

• increased glare at night

• altered color perception

cause of cataracts

aging; trauma; cogenital factors; metabolic disease; medications

treatment for cataracts

surgical removal of the cataracts w/ replacement of the lens

retinopathy

any disorder affecting the retina

causes of retinopathy

• trauma

• vascular disorder (diabetes, hypertension

retinal detachment

tearing of the retina from the choroid layer w/ seepage of vitreous humor behind retina causing further detachment

types of retinal detachment

• exudative (or serous)

• tractional

• spontaneous (or rhegmatogenous)

exudative (serous) retinal detachment

• accumulation of serous or hemorrhagic fluid in the subretinal space

• sudden

tractional retinal detachment

• injury or surgery to the eye

• most caused by

spontaneous (or rhegmatogenous) retinal detachment

• vitreous humor

• due to aging

clinical manifestations of retinal detachment

• sudden appearance of floating spots

• odd flashes of light

• blurring vision in a single eye that appears as a curtain being pulled down

if retinal detachment is untreated,

retina may detach entirely resulting in total blindness in affected eye

treatment of retinal detachment

diabetes is the leading cause of

new cases of blindness among working-age adults

diabetic retinopathy

• disorder of the retinal vessels

• formation of

  • microaneurysms & hemrrhage

  • neovacularization & subsequent leakage

proliferative

increased retinal detachment

age-related macular degeneration (AMD)

• progressive loss of central vision

• blurred vision

• wavy appearance of lines

atrophic (dry) age-related macular degeneration (AMD)

• more common

• change the macula of retina (yellow spot)

exudative (wet) age-related macular degeneration (AMD)

• more severe

• change the macula of the retina (yellow spot)

risk factors of age-related macular degeneration (AMD)

age; female; smoking; hypercholesterolemia; HTN; obesity

treatment of AMD

glaucoma

• decrease in outflow of aqueous humor (most common)

• gradual loss of vision in periphery

• bilateral, genetic

decrease in the outflow of aqueous humor =

increased intraocular pressure

gradual loss of vision in the periphery =

• tunnel vision

• vague/dull eye pain

• halos

• decreased color vision

treatment of glaucoma

• increase drainage

acute angle closure glaucoma

• narrow angle between pupil (iris) & later aspect of cornea

• leads to blockage of aqueous humor outflow when pupil is dilated

• less common

clinical manifestations of acute angle closure glaucoma

• severe eye pain

• nausea/vomiting

• blurred vision w/ halos around lights

• red eye

• dilated pupil nonreactive to light

acute angle closure glaucoma is more prevalent in

• older people

• hyperopia

• asians