Layers and Regions of the Ciliary Body

Question 1

Most of the ciliary body begins __ of the limbus. A small portion of the longitudinal muscle fibers are __ the limbus.

Answer 1

Outside

Within

Question 2

Anteriorly, the ciliary body is continuous with

Answer 2

The iris, uveal/trabecular meshwork, and scleral spur.

Question 3

Posteriorly, the ciliary body is continuous with

Answer 3

The choroid and retina

Question 4

Transition between the ciliary body and the retina/choroid is called the

Answer 4

Ora serrata

Question 5

Does the ciliary body extend further temporally or nasally?

Answer 5

Temporally

Question 6

What are the two regions of the ciliary body?

Answer 6

Pars plicata is the wider, anterior region.
-Contains the valleys of Kuhnt, with lesser processes that extend from these valleys.

Pars plana is the flatter, posterior region.
-Contains oral bays and teeth/dentate processes

Question 7

5 layers inner to outer

Answer 7

Inner (closer to ciliary body) 
1. Nonpigmented epithelium 
2. Pigmented epithelium 
3. Ciliary Stroma
4. Ciliary Muscle 
5. Supraciliaris 
Outer

Question 8

How many ciliary processes are located in the region of the pars plicata?

Answer 8

70-80 ciliary processes that extend into the posterior chamber.

Question 9

What produces aqueous humor and where does it flow

Answer 9

The pars plicata region of the ciliary process. Flows into the posterior chamber between the lens and the iris, through the pupil and into the anterior chamber.

Question 10

Valleys of Kuhnt are located where?
What creates the valleys?
What is within the valleys?

Answer 10

Located in the region of the pars plicata

• The valleys are created by the ciliary processes (shrimp)
• Within the valleys, there are smaller extensions called the lesser processes.

Question 11

Where does the pars plana extend from and to

Answer 11

Extends from the posterior pars plicata to the ora serrata

Question 12

What are the oral bays and teeth/dendate processes of the pars plana?

Answer 12

Oral bays- Project into the peripheral retina. Composed of ciliary stroma covered by pigmented and non=pigmented epithelium.

Teeth/dendate processes- located between oral bays. They are projections of peripheral retina.

Question 13

Which is more inner? The non-pigmented epithelium or the epithelium?

Answer 13

The non pigmented epithelium.

It is the most inner layer that lines the posterior chamber and part of the vitreous chamber.

Question 14

Zonules arise from the BM of which layer of cells

Answer 14

They arise from the BM of the non-pigmented epithelium. They insert into the lens capsule (which is the basement membrane of the lens) in the equatorial region of the lens. They suspend the lens in the posterior chamber.

Question 15

What is the non-pigmented epithelium continuous with anteriorly and posteriorly?

Answer 15

Anteriorly, it is continuous with the posterior pigmented epithelium of the iris. Basement membranes are continuous with one another.

Posteriorly, it is continuous with the neurosensory retina. The basement membrane is continuous with the inner limiting membrane of the retina (from the muller cells)

Question 16

The non-pigmented epithelium and the pigmented epithelium are base to base or apex to apex

Answer 16

Apex to apex

Question 17

The non-pigmented epithelium is what cell type

Answer 17

Simple columnar

Question 18

Pigmented epithelium is what cell type?

Answer 18

Simple cuboidal

Question 19

Pigmented epithelium is continuous with what, anteriorly and posteriorly?

Answer 19

Anteriorly, continuous with the pigmented epithelium of the iris. Basement membranes are continuous with each other.

Posteriorly, it is continuous with the RPE. basement membranes are continuous with each other.

Question 20

Ciliary stroma. What is it continuous with anteriorly and posteriorly?

Answer 20

Anteriorly, continuous with the iris stroma.

Posteriorly, continuous with the choroidal stroma.

Question 21

The ciliary stroma is composed of what?

Answer 21

Vascularized, loose connective tissue (collagen, fibroblasts, and ground substance). melanocytes and WBC’s

Question 22

The ciliary muscle is composed of which muscle fibers outer to inner?

Answer 22

Outer
1. Longitudinal
2. Radial 
3. Circular 
Inner

Question 23

Longitudinal muscle fibers of the ciliary muscle are connected to what structures anteriorly and posteriorly?

Answer 23

Anteriorly connected to the Trabecular/uveal meshwork and the scleral spur

Posteriorly, connected to the choroid in the form of stellate- shaped terminations called muscle stars

Question 24

Ciliary muscles are surrounded by

Answer 24

Ciliary stroma. It continues into the muscle layers.

Question 25

Supraciliaris is continuous with what?

Answer 25

Continuous with the suprachoroidal space

Question 26

What is the purpose of the supraciliaris?

Answer 26

Allows passage arteries/veins/nerves.
Transversed by thin, pigmented bands of loose connective tissue, allowing the ciliary body to slide against the sclera without detaching or stretching the tissue.