The document summarizes the anatomy and physiology of the anterior chamber angle and aqueous humor dynamics. It describes the structures forming the anterior chamber angle from posterior to anterior, including the ciliary band, scleral spur, trabecular meshwork, and Schwalbe's line. It also discusses the grading of angle widths, aqueous outflow system through the trabecular meshwork and Schlemm's canal, and the production and drainage of aqueous humor through trabecular and uveoscleral outflow pathways.

1. ANATOMY OF ANGLE OF
ANTERIOR CHAMBER
&
AQUEOUS HUMOR DYNAMICS
PRESENTED BY :-
VISHAL SIROHI (141)
&
VISHESH MOHAN SAXENA(142)

2. Anterior Chamber Angle
• Structures forming angle recess (from
posterior to anterior)

3. Ciliary Band
• Most posterior
landmark of the angle
which is viewed as a
dark band on
gonioscopy.
• Represents the
anterior face of ciliary
body including
insertion of ciliary
muscle into scleral spur
• Width depends on the
level of iris insertion.
• Wide in myopes and
narrow in
hypermetropes
• It appears as a grey /
dark brown band

4. Scleral Spur
• Wedge shaped
circular ridge
• Pale, translucent
narrow strip of
scleral tissue
• Marks the posterior
boundary of
corneo-scleral
meshworK

5. Trabecular Meshwork
• Broad band of tissue
extending from Scleral
Spur to Schwalbe’s Line
• No pigmentation at birth
but develops pigment with
increasing age (color varies
from faint tan to dark
brown)
• It is a sieve-like structure
through which aqueous
humour leaves the eye
• It consists of three
portions:-
a)Uveal meshwork
b) Corneoscleral meshwork
c)Juxtacanalicular meshwork

6. Schwalbe’s Line
• Anterior limit of the
drainage angle
• Seen as fine scalloped
border at the termination
of Descemet’s Membrane
of cornea.
• Width:- 50-150 µm
• Clusters of secretory cells ,
called schwalbe’s line cells,
produce a phospholipid
material that facilitates
aqueous humor flow
through the canalicular
system.

7. ANGLE OF ANTERIOR CHAMBER
(on gonioscopy)

8. GRADE ANGLE
WIDTH
(in degrees)
CONFIGURATI
ON
RISK OF
CLOSURE
STRUCTURES
VISIBLE ON
GONIOSCOPY
4 40 ֯ WIDE OPEN CLOSURE
IMPOSSIBLE
SL, TM, SS,
CBB
3 30 ֯ OPEN ANGLE CLOSURE
IMPOSSIBLE
SL, TM, SS
2 20 ֯ MODERATELY
NARROW
CLOSURE
POSSIBLE
SL, TM
1 10 ֯ VERY
NARROW
HIGH RISK OF
CLOSURE
SL ONLY
S <10 ֯ SLIT ANGLE CLOSURE
IMMINENT
ON ANGLE
STRUCTURES
SEEN
0 0 ֯ CLOSED CLOSED NONE OF THE
ANGLE
STRUCTURES
VISIBLE
SHAFFER’S SYSTEM OF GRADING
ANGLE WIDTH

10. Aqueous outflow system
• It includes:-
a) the trabecular meshwork,
b) Schlemm’s canal,
c) collector channels,
d) aqueous veins and the episcleral veins .

11. Trabecular meshwork
Cirular , spongy , sieve like connective
tissue lined by the trabeculocysts through
which the aqueous humor leaves the eye.

13. Trabecularmeshwork
Uveal meshwork
Corneoscleral
meshwork
Juxtacanalicular
meshwork

14. Uveal meshwork
• It is the innermost part of trabecular
meshwork
• Extends from the iris root and ciliary body to
the Schwalbe's line.
• The arrangement of uveal trabecular bands
create openings of about 25 m to 75 m.

15. Corneoscleral meshwork
• It forms the larger middle portion
• Extends from the scleral spur to the lateral wall
of the scleral sulcus.
• It consists of sheets of trabeculae that are
perforated by elliptical openings which are
smaller than those in the uveal meshwork (5 µ-50
µ).

16. Juxtacanalicular meshwork
• It forms the outermost portion of meshwork and
consists of a layer of connective tissue lined on
either side by endothelium.
• This narrow part of trabeculum connects the
corneoscleral meshwork with Schlemm’s canal.
• In fact the outer endothelial layer of
juxtacanalicular meshwork comprises the inner
wall of Schlemm’s canal.
• This part of trabecular meshwork mainly offers
the normal resistance to aqueous outflow.

17. Schlemm’s canal
• This is an endothelial
lined oval channel
present
circumferentially in the
scleral sulcus.
• The endothelial cells of
its inner wall are
irregular, spindle-
shaped and contain
giant vacuoles.
• The outer wall of the
canal is lined by smooth
flat cells and contains
the openings of
collector channels

18. Collector channels
• These, also called intrascleral aqueous vessels,
are about 25-35 in number and leave the
Schlemm’s canal at oblique angles to terminate
into episcleral veins in a laminated fashion.
• These intrascleral aqueous vessels can be divided
into two systems .
• The larger vessels (aqueous veins) run a short
intrascleral course and terminate directly into
episcleral veins (direct system).
• Many smaller collector channels form an
intrascleral plexus before eventually going into
episcleral veins (indirect system).

19. MOST OF AQUEOUS
VESSELS DRAIN INTO
EPISCLERAL VEINS
EPISCLERAL
VEINS
ANTERIOR
CILIARY &
SUPERIOR
OPHTHALMIC
VEINS
CAVER
NOUS
SINUS

21. Properties of Aqueous Humour

22. INTRODUCTION
• Is a clear, colourless, watery solution
• Flows from posterior to anterior chamber
• In healthy eye flow against resistance
generates 15 mm hg

23. Physio-chemical Properties
• Volume- about 0.31ml
a) 0.25ml in anterior chamber
b) 0.06ml in posterior chamber
• Refractive index: 1.336
• Density: Greater than that of water

24. Biochemical Composition
• Water: Constitutes of about 99.9% water
• Proteins (Colloid Content): 5-16mg/100ml
• Amino Acids
• Non-colloidal Constituents: Na, K , Ca, Mg, Cl,
HCO3 , Lactate, Pyruvate, Ascorbate, Urea,
Glucose

25. Functions of Aqueous Humour
• Serves to clear
blood,
macrophages,
remnants of
lens matter
from anterior
chamber
• Provides a clear
optical medium
for vision
• Acts as
diverging lens of
low power
• Provides
substrates
• Removes
metabolites from
cornea and lens.
• INFLATES THE
GLOBE
• MAINTAINS
STRUCTURAL
INTEGRITY
IOP
MAINTENAN
CE
Metabolism
Clearing
Function
Optical
Optical
Function

26. DYNAMICS INCLUDE
• Anatomy of aqueous formation and
drainage structures
• Aqueous humor formation
• Aqueous humor outflow

27. Primary ocular structures involved
are :-
1. Ciliary body
2. Posterior chamber
3. Anterior chamber
4. Angle of anterior chamber
5. Aqueous outflow system

28. CILIARY BODY
• Seat of aqueous production
• Triangular in shape
• Outer side- line with sclera with
a supra choroidal space in
betweeen
• Inner side of ciliary body has
two parts
a. Anteriorly pars plicata(finger
like projections-ciliary process)
b. Posteriorly pars plana
• Ciliary muscle- non striated
muscle
3 parts :-
1. Longitudinal or meridional
fibers- helps in aqueous
outflow
2. Circular muscles- helps in
accomodation
3. Radial or oblique fibers- helps
in aqueous out flow

29. CILIARY
PROCESS
• 70-80 in number
• 2 mm length and
5mm width
• Network of
capillaries
• Stroma
• Inner pigmented
epithelium
• Outer non
pigmented
epithelium

30. Physiology of
Aqueous
Production
Active
Transport
70%
Diffusion
10%
UltraFiltration
20%
• Three physiologic
processes
contribute to the
formation and
chemical
composition of the
aqueous humor.

31. ULTRAFILTRATION
• First of all, by ultrafiltration, most of the
plasma substances pass out from the capillary
wall, loose connective tissue and pigment
epithelium of the ciliary processes.
• Thus, the plasma filtrate accumulates behind
the nonpigment epithelium of ciliary
processes.

32. ACTIVE TRANSPORT
• The tight junctions between the cells of the non-
pigment epithelium create part of blood aqueous
barrier.
• Certain substances are actively transported (secreted)
across this barrier into the posterior chamber.
• The active transport is brought about by Na+-K+
activated ATPase pump and carbonic anhydrase
enzyme system.
• Substances that are actively transported include
sodium, chlorides, potassium, ascorbic acid, amino
acids and bicarbonates.

34. DIFFUSION
• Active transport of these substances across the
non-pigmented ciliary epithelium results in an
osmotic gradient leading to the movement of
other plasma constituents into the posterior
chamber by ultrafiltration and diffusion.
• Sodium is primarily responsible for the
movement of water into the posterior chamber
• Active Transport of substances described above
lead to osmotic and electrical gradient .
• To maintain the balance small partices like water
and small plasma constituents move in to post
chamber by diffusion.

35. AQUEOUS HUMOUR DRAINAGE
POSTERIOR CHAMBER
(through pupil)
ANTERIOR CHAMBER
TRABECULAR OUTFLOW UVEOSCLERAL
OUTFLOW

36. TRABECULAR OUTFLOW (70-
80%)

38. FREE FLOW OF
AQUEOUS OCCURS
FROM TRABECULAR
MESHWORK TO
JUXTACANALICULAR
TISSUE WHICH ALONG
WITH INNER WALL OF
SCHLEMM’S CANAL
APPEARS TO PROVIDE
SOME RESISTANCE.

39. Vacuolation theory
• VARIOUS MECHANISMS HAVE
BEEN PUT FORWARD FOR THE
FLOW OF AQUEOUS ACROSS
THE INNER WALL OF
SCHLEMM’S CANAL BUT THE
MOST ACCEPTED ONE IS THE
VACUOLATION THEORY.
• According to it, transcellular
spaces exist in the endothelial
cells forming inner wall of
Schlemm's canal.
• These open as a system of
vacuoles and pores, primarily in
response to pressure, and
transport the aqueous from the
juxtacanalicular connective
tissue to Schlemm’s canal .

40. • From Schlemm's canal the aqueous is
transported via 25-35 external collector
channels into the episcleral veins by direct
and indirect systems .
• A pressure gradient between intraocular
pressure and intrascleral venous pressure
(about 10 mm of Hg) is responsible for
unidirectional flow of aqueous.

41. UVEOSCLERAL OUTFLOW
(10-20%)