Test 4 section 1 Flashcards
(46 cards)
normal vision
emmetropia
nearsighted
myopia
farsighted
hyperopia
distortion caused by irregularity of cornea
astigmatism
measures intraocular pressure
tonometry
visualizes angle of anterior chamber
Gonioscopy
evaluates field of vision
perimetry testing
blind areas in visual field
scotomas
color vison test
Ishihara color test
used for judging distance
stereopsis
requires devices and correction lenses
Best corrected visual acuity (BCVA) of 20/70 to 20/200
low vision
BCVA 20/400 to no light perception
Blindness
is BCVA that does not exceed 20/200 in better eye or widest field of vision is 20 degrees or less
legal blindness
Normal IOP
10 ro 21 mm Hg
open-angle glaucoma pressure
22 to 32 mm Hg
acute angle-closure glaucoma pressure
> 50 mm Hg
type of glaucoma that is slow, with decreased peripheral and tunnel vision
open angle
type of glaucoma that is sudden, with excruciating eye pain, n/v, and redness
angle closure
unaware of condition until there is significant vision loss, peripheral vision loss, blurring, halos, difficulty focusing, difficulty adjusting eyes to low lighting
silent thief
an opacity or cloudiness of lens
cataracts
most common type of cataract
Altered metabolic processes cause accumulation of water and altered lens fiber structure
Senile cataract
removes entire lens
Rarely done today
Intracapsular Cataract extraction ICCE
maintains posterior capsule of lens, reducing potential postoperative complications
Extracapsular cataract extraction ECCE
an ECCE that uses an ultrasound device to suction lens out through a tube, incision is smaller than with standard ECCE
phacoemulsification
