shit to know about the eye (theory)

Question 1

IOP

Answer 1

intra-ocular pressure

normal IOP should be under 20 mmHG

if IOP becomes too high, it can result in glaucoma

Question 2

IOF

Answer 2

intra-ocular fluid

it’s made by the ciliary bodies and flows between the anterior and posterior chambers of they eye

Question 3

anterior chamber

Answer 3

the space between the cornea and iris

Question 4

posterior chamber

Answer 4

the space between the iris and the lens

Question 5

what are the 3 tunics of the eye

Answer 5

these are ways to categorize the parts of eye based on what they do and are made of

1. fibrous
2. vascular
3. nervous

Question 6

what falls under the fibrous tunic

Answer 6

1. cornea
2. sclera

Question 7

what falls under the vascular tunic

Answer 7

1. iris
2. ciliary body
3. choroid

Question 8

what falls under the nervous tunic

Answer 8

1. retina

Question 9

does the gel sit on the retina

Answer 9

yes, if detached due to head trauma, it must be re-attached to prevent vision loss

bleeding can occur between the detached retina and the gel

Question 10

order of the retina, choroid, and sclera

Answer 10

retina –> choroid –> sclera

Question 11

ocular conjunctiva

Answer 11

this is a thin clear membrane that sits over the sclera and appears white because of the underlying fibrous tunic

Question 12

conjunctivitis

Answer 12

inflammation of the conjunctiva, AKA pink eye

Question 13

where are the rods and cones
what is their function

Answer 13

they are in the retina and help with color vision and vision in darkness

cones = color vision
rods = help with low light vision

Question 14

which is more numerous, rods or cones

Answer 14

rods

Question 15

what is likely wrong when one has color blindness

Answer 15

likely the cones

Question 16

fovea centralis

Answer 16

this is a fovea located in the center of the macula (part of the retina) that is rich in cone photoreceptors

it allows for object focusing and high visual acuity

Question 17

macular degeneration

Answer 17

warped image as a result of damaged macula and weaker cone receptors

Question 18

optic disc

Answer 18

opposite to the fovea centralis, there are no receptors at all and this acts as a blind spot

Question 19

suspensory ligaments

Answer 19

these are ligaments that help keep the lens in position

Question 20

ora serrata

Answer 20

the ciliary muscle that is the transition between the ciliary body (serrated) to the retina (non serrated)

Question 21

function of the lens

Answer 21

the lens is biconvex and helps focus and image onto the retina, if the image lands directly onto the retina, you don’t need glasses

Question 22

near sightedness

Answer 22

a result of the lens producing and image that falls short of the retina

it can be corrected with a biconcave lens to push the image further back onto the retina

AKA myopia

Question 23

far sightedness

Answer 23

a result of the lens producing an image the falls past the retina

it can corrected with a biconcave lens (same shape as our lens) to move the image forward onto the retina

AKA hypometropia

Question 24

stigmatism

Answer 24

an issue with the cornea

normally, the cornea is a perfect curve, but when it becomes warped, it can produce a blurry image

Question 25

how to fix a stigmatism

Answer 25

use a cylindrical lens

Question 26

eye accommodation

Answer 26

the ciliary body contracts or relaxes depending on what object the eye is trying to focus on, this changes the shape of the lens and can result in lens bulging or relaxing

Question 27

lens bulging

Answer 27

when looking at a close object

the ciliary body contracts and relaxes the suspensory ligaments to bulge the lens

ex… when reading a book

Question 28

lens relaxation

Answer 28

when looking at a tree in the distance

the ciliary body relaxes and the suspensory ligaments pull the lens flat causing the lens to relax

Question 29

diabetics and retinal blood vessels

Answer 29

if your blood sugar is poor, it can results in retinal blood vessel damage