vision

Question 1

anterior and posterior segments of eye

Answer 1

slide 15

Question 2

what is the anterior segment of eye

Answer 2

ocular structure anterior to lens

Question 3

what is the posterior segment of eye

Answer 3

ocular structure posterior to lens

Question 4

where is in the anterior segment

Answer 4

anterior chamber (between cornea and lens) and posterior chamber (behind posterior of iris and in fornt of lens)

Question 5

what is anterior chamber filled with and function

Answer 5

clear aqueous fluid which supplies nutrients (cornea transparent so no blood vessels; receives glucose as O2 supplied from air)

Question 6

diagram of ciliary body

Answer 6

slide 16

Question 7

function of ciliary body

Answer 7

secretes aqueous fluid in the eye

Question 8

flow of aqueous fluid

Answer 8

ciliary body -> anteriorly into anterior chamber -> supplies nutrients -> drained out via trabecular meshwork

Question 9

2 drainage systems of aqueous fluid

Answer 9

trabecular meshwork canal of Schlemm 80-90%; uveal-scleral outflow passive absorption 10-20%

Question 10

diagram of aqueous fluid flow

Answer 10

slide 17

Question 11

what is glaucoma

Answer 11

sustainted raised intraocular pressure (typically >21mmHg; only modifiable risk factor) causing structural damage to optic nerve

Question 12

pathophsyiology of glaucoma

Answer 12

retinal ganglion death and enlarged optic disc cupping

Question 13

signs of glaucoma

Answer 13

visual field loss (brain fills patches of blindness with whatever around it), blindness

Question 14

2 types of glaucoma

Answer 14

primary open angle glaucoma (most common), closed angle glaucoma

Question 15

what causes primary open angle glaucoma

Answer 15

trabecular meshwork dysfunction

Question 16

pathophysiology of closed angle glaucoma

Answer 16

increased intraocular pressure pushes iris/lens complex forward, blocking trabecular meshwork -> vicious cycle

Question 17

risk factors for closed angle glaucoma

Answer 17

small eye (hypermetropia), narrow angle at trabecular network

Question 18

what may closed angle glaucoma present with

Answer 18

acute or chronic, so may present with sudden painful red eye with acute drop in vision

Question 19

closed angle glaucoma treatment

Answer 19

peripheral laser iridotomy to create iris drainage hole

Question 20

diagram showing primary open angle glaucoma vs closed angle glaucoma

Answer 20

slide 18