The document summarizes the anatomy and physiology of the aqueous humour in the eye. It describes how the ciliary body produces aqueous humour which flows into the posterior chamber. From there it passes through the pupil into the anterior chamber and exits through the trabecular meshwork into Schlemm's canal and collector channels for drainage into the episcleral veins. It maintains intraocular pressure and the optical and metabolic functions of the eye.

1. Optom
Askar.PK

2. AQUEOUS HUMOUR
 Concerned with it are ciliary body,
posterior chamber, anterior chamber angle
of the AC

3. Ciliary body
 It is the site of aqueous production

4. Posterior chamber
 Triangular space containing about
0.06ml aqueous humour
 Anteriorly: by the posterior surface of
the iris & part of CB

5. Cont……
 Posteriorly : by the crystalline
lens & its zonules
 Laterally: by the CB

6. Anterior chamber
 Anterior: back of cornea
 Posterior: anterior surface of iris &
part of CB
 3mm deep in the centre in normal
adult
 Comparatively shallow in very young
children & old people

7. Cont……….
 0.25ml of the aqueous
 Through pupil communicates with the
posterior chamber
 Peripheral recess: angle of AC ,
mainly formed by trabicular meshwork

8. Angle of the AC
An important role in the
process of aqueous drainage

9. Cont………………
 Structures:
1. The ciliary band
2. Scleral spur
3. Trabicular meshwork
4. Schwalbe’s line

10. 1. The ciliary band
 Most posterior landmark in
the angle recess.
 It is formed by the anterior
most part of the CB
 It appears as a grey or dark
brown band

11. 1. Sceral spur
 Posterior portion of the scleral sulcus
 Prominent white line on gonioscopy
 Posteriorly : CB, anteriorly:
corneoscleral meshwork

12. 1. Trabicular meshwork
 Seen as a band
 Just anterior to the scleral spur
 No pigment at birth & develops
pigments with increasing age

13. 1. Schwalbe’s line
 Fine ridge seen just in front of the
trabicular meshwork
 It is formed by the prominent end of
the decsemet’s membrane

14. Aqueous outflow system

15. 1. Trabicular meshwork
2. Schlemm’s canal
3. Collector channels
4. Episcleral veins

16. Trabicular meshwork
Sieve –like structure
Through which aqueous leaves the
eye
It is a complex connective tissue

17. Cont………..
1. Uveal meshwork
2. Corneoscleral meshwork
3. Justracanalicular meshwork

18. Uveal meshwork
 Innermost part of trabicular meshwork
 Extend from the iris root & CB to the
schwalbe’s line

19. Corneoscleral meshwork
 Large middle portion & extend from
the scleral spur to the lateral wall of
the sulcus

20. Jstracanalicular meshwork
 Form the outer most portion of the
trabicular meshwork

21. Schemm’s canal
 Endothelial lined oval channel
present circumferentially in the
scleral sulcus
 Endothelial cells of its inner
wall are irregular & spindle
shaped

22.  Collector channels
 Also called intrascleral aqueous
vessels
 About 25-35 in number & leave the
schlemm’s canal

23.  Episcleral veins
 Most of the aqueous vessels drain into
vein
 Episcleral vein ultimately drain into the
cavernous sinus

24. Physiological
consideration

25. Functions
 Clear, colourless, watery solution
 Continuously circulated from the
posterior chamber of the eye
throughout the anterior chamber

26. Cont…
1. Maintenance of intraocular pressure
2. Metabolic role
3. Optical function
4. Clearing function

27. Physiochemical properties
 Volume: 0.31ml
 RI : 1.336
 Density : slightly greater than that of
water
 Osmotic pressure: slightly
hyperosmotic to plasma (3-5 mOsm/l)
 pH: acidic (7.2)
 Rate of formation : 2.3 micro l /min

28. Aqueous humour dynamics
 Aqueous dynamics include aqueous
formation & drainage
 Aqueous production remain constant
till IOP is raised to 50 mmHg & over

29.  Aqueous humour flow from the
posterior chamber into the AC
through the pupil
 From AC aqueous is drained out by
two routes : uveoscleral outflow ,
trabicular out flow

30. Intraocular pressure
 The IOP refers to the pressure exerted
by intraocular contents on the coats
of the eyeball
 The normal level IOP is essentially
maintained by a dynamic equilibrium
b/w the aqueous humour formation
aqueous humour outflow & episcleral
pressure

31. Cont…
 IOP is distributed evenly throughout
the eye
 The IOP important in maintaining the
shape of the eyeball
 Normal IOP varies b/w 10.5 to 20.5
mmHg

32. Thank you