OAH - Anterior chamber

The anterior boundary of the anterior chamber is the...

Posterior surface of the cornea

The posterior boundary of the anterior chamber is the...

ABL of the iris and the anterior surface of the lens

The lateral boundary of the anterior chamber is the...

- Face of the CB
- Trabecular meshwork
- Angle structures

What is the volume of the anterior chamber?

250 microliters

The shape of the anterior chamber is...

Ellipsoid

Where is the anterior chamber angle?

Where the iris and cornea meet

What is the depth of the anterior chamber?

3.5 to 3.7mm

What is the diameter of the anterior chamber?

11.3 to 12.4mm

The angle narrows as....

We age

Do myopes have more open or closed angles?

Open

Do hyperopes have more open or closed angles?

Closed

Do blacks or asians have more narrow angles?

Asians

Do males have larger angles than females?

Yes

The anterior chamber is a pathway for....

AQ to exit the eye

How is the anterior chamber self cleaning?

Phagocytosis

What is the rectifying property of the anterior chamber?

AQ flows through 1 way out of the angle and into Schlemms canal

What are the 2 major pathways for AQ to exit the eye?

- Conventional
- Uveoscleral

The conventional pathway involves the....

Trabecular meshwork

Which is the most used AQ pathway?

The conventional pathway (80%)

What is the collagen core of the trabecular meshwork?

- Type 1 tensile
- Type 3 resilience

What surrounds the collagen?

Elastin to allow reversible deformation

What covers the collagen core?

Endothelium

How many cords of meshwork are in the uveal meshwork?

2 to 3 layers

The uveal meshwork has large...

Intratrabecular spaces

The uveal meshwork is involved in...

Gross filtration

What is adjacent to the anterior chamber?

The uveal meshwork

How many sheets are in the corneoscleral meshwork?

20 with pores

Pores get smaller as you get closer to...

Schlemms canal

The anterior trabecular meshwork is the...

Non filtering part

What is the most anterior structure of the angle?

Schwalbes line

What is Schwalbes line?

The transition between the trabecular meshwork and corneal endothelium

Schwalbes line is a ring of....

Collagen and elastin

What is the pigmented Schwalbes line called?

Sampaolesis line

Posterior embryotoxon is when...

Schwalbes line is anteriorly displaced and thickened

The scleral spur is adjacent to...

Schlemms canal

Does the spur have more elastin fibres?

Yes

The trabecular meshwork attaches to the...

Spur

The CB attaches to the...

Spur

The corneal endothelium and trabecular meshwork endothelium are both....

Metabolically active, but not under normal conditions

Endothelia increase in size with...

Age

The trabecular meshwork carries out cleaning by....

Engulfing and ingesting debris

What parts of the trabecular meshwork regulate smooth muscle?

- Transporters
- Channels
- Receptors

Rhokinase inhibitors relax...

Trabecular meshwork endothelial cells to relax and open the angle to lower IOP

What can rhokinase enhance?

Episcleral outflow

What makes up the JCT?

- Collagen fibres
- GAGs

How does the JCT slow AQ flow?

It is very viscous

What offers the greatest resistance to AQ outflow?

The JCT

What do juxtacanalicular cells produce?

Extracellular substances like GAGs

How do juxtacanalicular cells prevent separation of Schlemms canal from the trabecular meshwork?

It uses cytoplasmic processes

What does the cribriform plexus contain?

Elastic fibres that connect juxtacanalicular tissues and the inner wall of Schlemms canal to the longitudinal muscle fibres of the CB

Contraction of the ciliary muscle enhances....

AQ outflow

What is the shape of Schlemms canal?

Oval lymphoid like sinus that runs 360 degrees in the internal scleral sulcus

What is the circumference of Schlemms canal?

36mm

The inner wall of Schlemms canal contains...

Discontinuous zonula occludens

AQ flows through pinocytosis in...

Schlemms canal to create pressure

Giant vacuoles are formed by what?

Endothelial cells of the inner wall of Schlemms canal in response to pressure

What prevents AQ regurgitation?

The vacuoles open up on the lumen side only

The higher the pressure, the more we have...

Larger vacuoles so it is pressure dependent

Sondermanns are...

Outpouchings of the inner wall of Schlemms canal

What do Sondermanns do?

They increase surface area to make way for more giant vacuole formation

Efferent collector channels exit through the...

Outer wall of Schlemms canal

Collector channels drain AQ into.....

- AQ veins
- Several venous plexi

Venous plexi drain into...

Ophthalmic veins

There is a direct connection between the venous system and Schlemms canal, so pressure can....

Cause blood regurgitation back into the canal

Blood regurgitation can become a long term issue by...

Creating secondary glaucoma

Why can blood not enter the anterior chamber?

Because of zonula occludens of the inner wall

Where does AQ enter the uveoscleral pathway?

The face of the CB or the ABL of the iris

Where does AQ go after the CB or ABL of the iris?

Between ciliary muscle fibres

Where does AQ go after going between ciliary muscle fibres?

The supraciliary space

Where does AQ ultimately drain?

Vortex veins