Eye Flashcards
it is a transparent membrane mucous that covers the anterior surface of the eye
conjunctiva
gland that secretes tears
lacrimal gland
a small duct that collects the excess tears
lacrimal canaliculi
helps maintain the shape of the eye, protects the internal structures andd provides attachments for the sites for eye muscle
sclera
very thin structure consists of a vascular network and many melanin-consisting pigments, appearing black
choroid
colored part of the eye
iris
opening of the eye
pupil
type of retina that keeps light from reflecting back into the eye
pigmented
two layers of retina
sensory and pigmented
type of retina that contains photoreceptor and interneurons
sensory
true of false
rods are 20 times more than cones
true
photoreceptor cells that can function / require low level of light to stimulate. it does no provide color vision
rods
photoreceptor cells that provide color vision and require more light
cones
it contains no photoreceptor, called as blind spot
optic disc
its presence keeps the eye inflated and maintain the pressure withtin the eye. (it circulates) if the pressure increases above the normal range, it can cause glaucoma
aqueous humor
jelly like subtance that helps maintain pressure within the eye and holds the lens and the retina in place. it laso refracts light and does not circulate
vitreous humor
a person with vit a deficiency has a condition called?
night blindness
is involuntary oscillation of the eyeball
Nystagmus
is a condition in which there is deviation
from perfect ocular alignment
Strabismus
Visual Acuity Test
Snellen chart: distance
___: near
Rosenbaum pocket screener
This is important when screening patients for ocular trauma or for neurologic disorders
PTOSIS
DIAGNOSTIC EVALUATIONS
The examiner holds the ophthalmoscope in the right hand and uses the right eye to examine the patient’s right eye.
The examiner switches to the left hand and left eye when examining the patient’s left eye.
During this examination, the room should be darkened, and pt’s eye should be on the same level as the examiner’s eye.
Dark room- dilate, red reflex
Direct Ophthalmoscopy
(red smudges –
hypertension)
Intraretinal hemorrhages
- lipid has yellowish appearance.
Hypercholesterolemia or DM
- little red dots, and nevi.
Microaneurysms
- Drusen (yellowish areas)
Macular degeneration
test to know if there is any color blindness
ishihara test
Used for patients with macular problems, such as macular degeneration.
Each eye is tested separately. The patient is instructed to stare at the central fixation spot on the grid and report any distortion in the squares of the grid itself.
AMSLER GRID
Valuable diagnostic technique when the view of the retina is obscured by opaque media such as cataract or hemorrhage.
Used to identify orbital tumors, retinal detachment, vitreous hemorrhage, and changes in tissue composition
Minimal discomfort for the patient.
ULTRASONOGRAPHY
Technology that involves low-coherence
interferometry.
This method is noninvasive and involves no physical contact with the eye.
TOMOGRAPHY
used to detect and document retinal lesions.
Pt’s pupils are widely dilated before the procedure.
Visual acuity is diminished for about 30 minutes as a
result of retinal “bleaching” by the intense flashing
lights.
mydriatics - nagpapadilate ng mata
FUNDUS PHOTOGRAPHY
topical medication to dilate the pupil before any procedures
mydriatics
It is an invasive procedure in which fluorescein dye is injected, usually into an antecubital vein.
Within 10 to 15 seconds, this dye can be seen coursing through the retinal vessels.
Over a 10-minute period, serial black-and white photographs are taken of the retinal vasculature.
Dye may impart a gold tone to the skin and urine may turn deep yellow or orange. This discoloration usually disappears in 24 hours
Antecubital - inject the dye
FLUORESCEIN ANGIOGRAPHY
Measures IOP by determining the pressure necessary to indent or flatten (applanate) a small anterior area of the globe of the eye.
The procedure is noninvasive and usually painless. A topical anesthetic eye drop is instilled in the lower conjunctival sac, and the tonometer is then used to
measure the IOP.
TONOMETRY
Normal eye pressure ranges from
10-21 mm Hg
Can be corrected by lenses that focus
light rays on the retina
Refractive errors
Evaluates the field of vision
Visual field testing (ie, perimetry) helps identify
which parts of the patient’s central and peripheral
visual fields have useful vision.
Helpful in detecting blind areas in the visual field
in macular degeneration and the peripheral field
defects in glaucoma and retinitis pigmentosa.
PERIMETRY TESTING
- handheld device that gently taps the front of the eye to obtain a pressure
reading.
TONOPEN
nearsighted
Myopia
normal vision is also called
Emmetropia
farsighted
Hyperopia
distortion caused by irregularity of
the cornea
Astigmatism
BCVA 20/400 to no light perception
Legal blindness is BCVA that does not exceed
20/200
Financial Assistance
BLINDNESS
Requires devices and strategies in addition to
corrective lenses
Best corrected visual acuity (BCVA) of 20/70 to
20/200
LOW VISION
An opacity or cloudiness of the lens
Leading cause of blindness in the world
Three types
1. Traumatic
2. Congenital
3. Senile cataract
CATARACTS
drops to paralyze eye
cycloplegics
often is accompanied by
functional impairment (cane, guide dog) and should be
encouraged to learn
Braille and to use computer aids
Impaired vision
all eye conditions are painless except to this one
closed angle glaucoma
Ocular conditions in which damage to the optic nerve
is related to IOP caused by congestion of the
aqueous humor.
Increased IOP damages the optic nerve and nerve
fiber layer, but the degree of harm is highly variable
Glaucoma is the second leading cause of blindness in
adults in US.
Loss of peripheral vision
There is no cure for glaucoma, but can be controlled
GLAUCOMA
TYPES OF CATARACT SURGERY
In this method of extracapsular cataract surgery, a portion of the anterior capsule is removed, allowing extraction of the lens nucleus and cortex while the posterior capsule and zonular support
are left intact.
An ultrasonic device is used to liquefy the nucleus and cortex, which are then suctioned out through a tube
After the pupil has been dilated, a small incision is made on the upper edge of the cornea, clear gel is injected into the space between the cornea and the lens to prevents the space from collapsing
and facilitates insertion of the IOL.
Incision is smaller so wound heals more rapidly
PHACOEMULSIFICATION
TYPES OF CATARACT SURGERY
After removal of the crystalline lens, the patient is
referred to as aphakic (without lens).
LENS REPLACEMENT
