Anatomy Whole Term Review Flashcards
Which structure provides structure and nourishment to the retina?
choroid
Which structure(s) produces the aqueous humor?
ciliary bodies
Name three structures that provide protection for the eye.
bony orbit, conjunctiva, lacrimal system
What is the jelly-like substance, thick and viscous, that occupies the chamber in the posterior concavity of the eyeball?
vitreous humor
Which structure has the function of focusing light especially in near objects?
lens
The pupil is formed by which structure?
iris
Cones are responsible for sensing what two things?
color and fine detail
Which time on a clock describes the position of inferior rectus?
6 o’clock
What part of the skull encloses the eyes?
bony orbits
Which structure is the link between the visual system and the brain?
optic nerve
What time on a clock describes the position of the superior oblique rectus of the right eye?
2:00 (definitely not 7:00)
What structures are found in the anterior chamber of the visual system?
aqueous humor and cornea
What is the main structure involved in the bending of light?
cornea
If poor drainage of aqueous humor is an issue, which structure(s) could be be affected?
canal of Schlemm
What structure(s) produce tears?
lacrimal gland
What are the 5 categories of visual dysfunction?
visual acuity, field, binocularity, color perception, CVI
What are 3 things that cause all acuity problems?
refractive errors, diseases, syndromes
Which dysfunction is being described? “The sharpness of vision at a designated distance”
visual acuity
A normal eye generates how many diopters?
60
What is the term that means bending of light?
refraction
When an image is focused before it reaches the retina, because it is bending too much, that’s called…
myopia
What are the 4 refractive errors?
myopia, hyperopia, astigmatism, presbyopia
What is the term for unaligned eyes?
strabismus
What is the term for lack of symmetry in the curvature of the cornea?
astigmatism
What is the unit for measuring the amount of refraction?
diopters
Macular degeneration mainly causes which type of visual dysfunction?
visual field loss
Which term means binocular (both eyes) double vision?
diplopia
The area that can be seen by looking straight ahead
visual field
What unit is used to measure the visual field?
degrees
Is astigmatism related to where an image lands on the retina?
no- it’s related to the shape/curvature of the cornea
What is the main function of the bony orbit?
to protect the eyeballs
What is the thin layer that covers the eyes, attaches to eyelids, and protects the eyes?
conjunctiva
Which structure is the major refractor in the eye?
cornea
How much of the light bending in the eye does the cornea do?
90%
Where is the anterior of the eye? From the __ to the __
from the cornea to the iris
Which structure drains the occleus to keep pressure down?
Canal of Schlemm
What surrounds the lens, keeps it in place, is attached to ciliary bodies, and are most involved in the process of focusing?
Zonules of Zinn
What area in the retina provides sharp vision with the greatest detail?
macula
Which structure is the sentry/file station, and sorts information?
geniculate bodies
At what time on a clok face is the medial rectus positioned? (looking at right eye)
3:00, by the nose
At what time on a clock face is the lateral rectus positioned? (looking at right eye)
9:00, by the temple
At what time on a clock face is the superior rectus positioned?
12:00
At what time on a clock face is the inferior rectus positioned?
6:00
Which muscle moves the eye UP?
superior rectus
Which muscle moves the eye DOWN?
inferior rectus
Which muscle moves the eye IN?
medial rectus
Which muscle moves the eye OUT?
lateral rectus
What should a child be wearing during an eye exam?
Their best glasses or contacts, so it can be determined how well the child can see with correction.
Part of retina made mostly of cones, center of macula, provides sharp vision
fovea
Colored part of the eye, controls the amount of light that enters the eye, helps sharpen focus
iris
If problems in this part of the eye, a person might experience photophobia, too much light, glare, loss of acuity, pain, too little light
iris
Which structure protects and cares for the eye through controlling tears?
lacrimal system
Structure that changes shape/thickness to add bending power for closer viewing (accommodation)
lens
Where cataracts form
lens
Part of the retina with the highest concentration of cones, used for reading very small print, central visual field is here
macula
What is ARMD?
age related macular degeneration
Where information from both eyes cross to create a complete visual picture. Nerves from each eye come together and are split so information from both eyes is shared with both parts of the brain
optic chiasm
Where optic nerve and retinal blood vessels enter and optic nerve attaches from the brain, where the blindspot is in each eye
optic disc
Bundle of nerves that carry information from the retina to the brain
optic nerve
What is the most common eye condition related to optic nerve damage caused by abnormally high pressure in the eye
glaucoma
Which structure is in the corner of the eye, pink skin that covers gland
coruncula
What structures make up the uveal tract?
choriod, ciliary body, iris
What does the ciliary body produce?
aqueous humor
Perceives fine details, color, color contrast, clear vision, and objects positioned in the central portion of vision
cones
How many cones and rods do we have?
6 million cones, 120 million rods
What is concentrated in the fovea, which is the center of the macula?
cones
Crystalline is another name for which part of the eye?
lens
Where does the optic tract start? Where does it go next?
starts at the optic chiasm and goes to the geniculate bodies, then onto the brain
Where is the posterior chamber? Behind the __ and in front of the __.
behind the iris and in front of the lens
Hole in the top and bottom lid to collect tears
punctum
Opening of the iris, hole that expands and contracts as the iris changes shape
pupil
Nerve layer lining 2/3 of the back of the eye, connected to our brain
retina
Disorder that affect babies born too early, before blood vessels have developed to the edge of retina, so abnormal blood vessels develop which are fragile and weak, and as they scar they shrink, pull on the retina and detach it
ROP - retinopathy of prematurity
Perceive movement and objects in low light, as well as objects located in the edges of vision, no color, found in greater number around the edges of the retina
rods
Congenital eye disorder that first affects the rods and leads to decreased night vision
RP - retinitis pigmentosa
The white part of the eye, tough outer wall that with the cornea forms the external coat of the eye, also forms protective sheath around the optic nerve.
sclera
Fibers that connect the ciliary body of the eye with the lens, holding it in place
suspensory ligaments
Dots along the base of bottom lid that produce oils and prevent evaporation and prevent tear spillage onto the cheek making closed lids airtight
tarsal glands
Serve to clean and lubricate the eyes in response to irritation, produced by the lacrimal gland
tears
Layer of tissue between the outer and inner layers of the eye
uveal tract
AKA Occipital lobe
visual cortex
AKA Visual cortex
occipital lobe
Which part of the brain is involved with spatial organization of a scene, shapes, brightness and shading?
primary visual cortex
Which part of the brain interprets patterns?
secondary visual cortex
Supports the retina against the choroids, provides structure and shape of the eye, fills up central cavity
vitreous humor
What are the 6 refractive structures, in order?
TCCALV - tears, conjunctiva, cornea, aqueous, lens, vitreous
Eye condition caused by high pressure in the eye
glaucoma
What two structures make up the outer layer of the eye, and in what proportions?
sclera is 5/6 and cornea is 1/6
Which system of structures provides light absorption? What three structures are included?
uveal tract - iris, choroid, ciliary bodies
Which part of the brain is the center for visual learning and recognition by sight?
temporal lobes
Which part of the brain is the limbic sector and guides visual attention and is involved with emotional responses?
midbrain
Which cranial nerve is responsible for most eye movement, pupil, and lid function?
3rd cranial nerve
Which cranial nerve works the superior oblique and may cause double vision, manifested by a head tilt?
4th cranial nerve
Which cranial nerve is responsible for the lateral rectus?
6th cranial nerve
What is measured by determining the smallest object or line seen clearly at a set distance?
visual acuity
What does 20/30 vision mean?
you can see at 20 feet what a person with “normal vision” can see at 30 feet - less acuity than the average person (worse vision) - the higher the bottom number, the less visual acuity a person has
On an eye prescription, what does OD mean?
right eye
On an eye prescription, what does OS mean?
left eye
On an eye prescription, what does OU mean?
both eyes
On an eye prescription, what does + mean?
farsighted, so need to add (+) more bend
On an eye prescription, what does - mean?
nearsighted, so need to decrease (-) bend
On an eye prescription, what does AXIS refer to?
astigmatism
On on eye prescription, what is the range for sphere?
1 - 9 diopters
What is the benchmark for legal blindness?
20/200 with correction, with both eyes
How many diopters are generated by an eye?
60
Of the 60 diopters per eye, how many are from the cornea?
40 diopters from the cornea
Which refractive error requires a concave lens?
myopia
Which refractive error requires a convex lens?
hyperopia
Which refractive error is caused by a loss of accommodation, usually in 40+ yrs olds?
presbyopia
Which term refers to the ability to adjust the focus on an object being viewed?
accommodation
Area of space above, below, left and right when visible while looking straight ahead
visual field
Each eye sees how many degrees horizontally?
160 degrees
How many degrees of overlap are there between the two eyes when working together?
60 degrees
Blind spots within the visual field
scotomas
Any condition affecting the retina will affect which visual dysfunction?
visual field
What term describes the hemisphere you can’t see?
hemianopsia
Visual field losses can be described as __ or __
lateral or central
Using two eyes together to form a three-dimensional object
stereopsis
Ability to see the world in 3-d and perceive distance using cues from one or both eyes
depth perception
Double vision
diplopia
Double vision in just one eye
monocular diplopia
When the brain fails to process input from one eye and over time favors one eye over the other (lazy eye)
amblyopia
When an eye turns in, toward the nose
esotropia
When an eye turns out, toward the temple
exotropia
When an eye turns downward
hypotropia
When an eye turns upward
hypertropia
Involuntary movement of the eye
nystagmus
Which visual dysfunction is primarily inherited?
color perception
Loss of cone receptors which results in total loss of color vision
achromatopsia
School activities that will provide challenge for those with color perception problems
maps, charts, graphs, color coding