Choroid B6

Question 1

What is the middle layer of the eye?

Answer 1

Uvea

Question 2

Uveal tract is composed of 3 regions from back to front?

Answer 2

Choroid
Ciliary body
Iris

Question 3

The uvea is sometimes called what tunic?

Answer 3

Vascular tunic, because it has the choroid that is composed of mainly blood vessels, which supply the outer retinal layers

Question 4

The choroid extends from the __________ to the _________ and is located between the _________ and the ___________, providing nutrients to outer retinal layers.

Answer 4

ora-serrata
optic nerve

sclera
retina

Question 5

Choroid consists primarily of what?

Answer 5

blood vessels, but has a thin connective tissue layer that lies on each side of the stromal vessel layer

Question 6

The choroid is bordered on both sides by a connective tissue layer, what are they.

Answer 6

Suprachoroid

Bruch’s membrane

Question 7

Layers of the choroid (from superficial to deep)

Answer 7

Suprachoroid Lamina
Choroidal Stroma
Choriocapillaris
Bruch’s membrane

Question 8

Suprachoroid lamina is loose, why is this important?

Answer 8

Looseness of the tissue allows the vascular net to swell without causing detachment.

Question 9

The long posterior ciliary arteries and nerves run in what space to the front of the globe?

Answer 9

Suprachoroidal space (IMPORTANT)

Question 10

This is a pigmented, vascularized, loose connective tissue layer containing melanocytes, fibroblasts, macrophages, lymphocytes, and mast cells.

Answer 10

Choroidal stroma

Question 11

Branches of the short posterior ciliary arteries run in what space?

Answer 11

Choroidal stroma

Question 12

Outer layer of choroidal stroma with vessels that are LARGER

Answer 12

Haller’s Layer

Question 13

Middle layer of vessels of choroidal stroma with vessels that are smaller and continue to branch into capillary bed.

Answer 13

Sattler’s layer

Question 14

Sympathetic innervation of choroidal stroma.

Answer 14

Causes vasoconstriction and decreased choroidal blood flow. From sympathetic trunk of carotid plexus via ciliary ganglion

Question 15

Parasympathetic stimulation of choroidal stroma.

Answer 15

Causes vasodilation, resulting in increased blood flow. Comes from inferior division of CN III via ciliary gang.

Question 16

Choroidal veins contain no _______.

Answer 16

valves

Question 17

What are the main drainage of blood in choroidal stroma?

Answer 17

Large vortex pattern

Question 18

This is a specialized capillary bed, forms a single layer of anastomosing, fenestrated capillaries having wide lumina with most of the fenestrations facing toward the retina.

Answer 18

Choriocapillaris (lamina choroidocapillaris)

Question 19

These may have a contractile function and are found around the capillary wall. Have ability to alter local blood flow.

Answer 19

Pericytes (rouget cells)

Question 20

The choroiocapillaris is densest in the ____________ area, where it is the sole blood supply for this small region of the retina.

Answer 20

macular

Question 21

The deepest/ innermost layer of the choroid.
Fuses with the retina
Runs from optic nerve to ora-serrata
Undergoes modification before continuing into ciliary body

Answer 21

Bruch’s membrane (Basal lamina)

-has a lot to do with macular area and macular degeneration

Question 22

Composition of Bruch’s membrane: multilaminated sheet containing a center layer of elastic fibers. Outer to inner superficial to deep. What are the 5 layers?

Answer 22

Interrupted basement membrane of choriocapillaris
Outer collagenous zone
elastic layer
inner collagenous zone
basement membrane of RPE cells

Question 23

Fine filaments from the _____________ of the Retinal pigmented Epithelium (RPE) merge with the fibrils of the inner collagenous zone, makes tight adhesion with choroid and pigemented layer of retina.

Answer 23

basement membrane 
(important in retinal detachment)

Question 24

3 functions of choroid?

Answer 24

Provide nutrients to outer retina
Absorbs excess light
Pathway for the posterior vessels and nerves that supply the anterior seg

Question 25

Explain some of the uveal blood supply and venous drainage.

Answer 25

Short posterior ciliary arteries enter the globe in a circle around the optic nerve, and their branches form the choroidal vessels.
Venous drainage for most of the Uvea is through Vortex veins

Question 26

Sensory innervation of Uvea is provided by?

Answer 26

Nasociliary branch of CN 5 V1

Question 27

With aging, excessive basement membrane (basal lamina) material is deposited in the collagenous zones of Bruch’s membrane. These deposits in the inner collagenous zone is called _________.

Answer 27

Drusen

Question 28

Cones are good at

Answer 28

Macula, color, and precision

Question 29

Rods are good at

Answer 29

Light and motion