topic 4 uveal tract

Question 1

what 3 structures make up the uveal tract?

Answer 1

iris, ciliary body, choroid

Question 2

what are the 2 zones in the iris? what are the demarcated by?

Answer 2

pupillary and ciliary zones

colarette

Question 3

what are the 3 layers of the iris? give brief descriptions of them

Answer 3

1. ant. border layer (ant most, provides colour has melanocytes)
2. iris stroma (contains connective tissue and pigment cells)
3. iris pigmented epithelium (post. most layer. double layers, both pigmented)

Question 4

what are the 2 muscles found in the iris? which region are they found and how are they arranged?

Answer 4

1. dilator muscle
   lies in ciliary zone in ant. epi region. radially arranged
2. sphincter muscle
   lies in pupillary zone in iris stroma. encircles pupil

Question 5

what is the innervation of these 2 muscles?

Answer 5

dilator: sympathetic innervation. dilates pupil
sphincter: parasym innervation. constricts pupil

Question 6

what does the choroid contain? what is its function?

Answer 6

contain blood vessels and pigment cells

function: provide nutrition to outer retina

Question 7

what are the 4 layers of the choroid outer to inner?

briefly describe them

Answer 7

1. suprachoroid: contains connective tissues, blood v and nerves. closest to sclera
2. stroma: contains blood v and pigment
3. choriocapillaries: supply nutrition to (outer retina)
4. bruch’s membrane: aids passage of nutrients to retina

Question 8

what are the 2 regions of the ciliary body?

Answer 8

pars plicata (ant. closer to iris) and pars plana (post. closer to choroid)

Question 9

what are the 2 main functions of the ciliary body?

Answer 9

helps with accommodation (ciliary muscles)

site of aq prod. (INPCE of ciliary processes which in in pars plicata region)

Question 10

what are the 3 layers of the ciliary body? briefly describe them

Answer 10

c. muscle (outer)
c. stroma (contains blood v, connective tissues and pigments)

c. epithelium (inner)
double layered, outer is pigmented and inner in non pigemented

Question 11

what is the blood supply for the uveal tract? where is it located?

Answer 11

MAC which is made of 2 long post. ciliary arteries and 7 short ant ciliary arteries.
it is located in the iris stroma near the iris root, towards the ciliary stroma

Question 12

what is the nerve supply of the uveal tract?

Answer 12

1. trigeminal nerve (CN V)
   for all 3 structures
2. oculomotor nerve (CN III)
   only for iris and ciliary body
   allows for pupillary action