The anterior chamber angle structures and aqueous outflow system were summarized. The anterior chamber is bounded anteriorly by the cornea and posteriorly by the iris and lens. It contains aqueous humor and drains through the trabecular meshwork into Schlemm's canal and collector channels. Key angle structures include Schwalbe's line, trabecular meshwork, scleral spur, and ciliary body. Gonioscopy allows visualization and grading of the anterior chamber angle and is important for glaucoma evaluation and treatment planning.

1. Moderator: Dr. Deepika
M Presenter: K. Sahithi
Reddy 2K14,
ANGLE OF
ANTERIOR
CHAMBER
Date: 10-07-

2. INDEX:
• Anterior Chamber
• Angle of anterior chamber
• Development
• Aqueous outflow system
• Importance of Angle of
anterior chamber
• Diagnostic modalities

3. ANTERIORCHAMBER:
• Anterior chamber is an
angular space.
• It is the space formed
Anteriorly by the
posterior
surface of cornea
Posteriorly by the lens
within the pupillary aperture,
anterior surface of iris and a
part of cilary body

4. • Anterior chamber Is 3mm
deep and it contains 0.25ml
of aqueous humour.
• Anterior chamber depth is
shallower in the
hypermetropic eye than the
myopic eye.
• It is also shallower in
children and older people.
• Chamber depth decreases
by 0.01mm/year of life

5. • Chamber depth is slightly diminished during accommodation,
partly by increased lens curvature and partly by forward
translocation of lens.

6. • 1. Schwalbe’s line
• 2. Trabecular Meshwork
• 3. Scleral spur
• 4. Anterior most part of ciliary
body
• 5. Root of Iris

7. Schwalbe’sLine:
• This marks the anterior
border of angle and
represents termination of
descemet’s membrane.
• Seen as glistening white
line in gonioscopy.

8. • Schwalbe’s line marks
transition from
Trabecular to
cornea
endothelium.
Termination of the
Decemet’s membrane.
Insertion of trabecular
meshwork into corneal
stroma.

9. TRABECULARMESHWORK:
• It is a sieve like structure
made up of connective
tissue lined by
trabeculocytes, which have
contractile and phagocytic
properties.
• Its main function is in
drainage of aqueous
humour.

10. • The meshwork is roughly triangular in cross
section;
• Apex is at the Schwalbe’s line
• Base is formed by the scleral spur and ciliary
body.

11. SCHLEMM’SCANAL
• Schlemm’s canal is a circular lymphatic like
vessel in the eye that collects aqueous
humour from the anterior chamber and
delivers it into the episcleral blood vessels
via aqueous veins.

12. COLLECTORCHANNELS
• Schlemm’s canal is connected
to episcleral and conjunctival
veins by a complex system of
intrascleral channels.
• Two systems of intrascleral
channels have been identified:
(a)Indirect system
(b)Direct system

13. (a) INDIRECTSYSTEM
• Indirect system consists of
15- 20, finner channels,
which form an intrascleral
plexus before eventually
draining into the episcleral
venous system
The intrascleral plexus is the network of blood vessels
within the substance of the sclera

14. (b) DIRECTSYSTEM:
• Direct system consists of large
caliber vessels, which run a
short intrascleral course and
drain directly into the
episcleral venous system,
they are about
6-8 in number and also called
as aqueous veins.
• These aqueous vessels
terminate into the episcleral
and conjunctival veins in
laminated junction- it is called
LAMINATED VEIN OF
GOLDMANN

15. EPISCLERALANDCONJUNCTIVALVEINS
• Most aqueous vessel are
directed posteriorly, with
most of these draining into
episcleral veins, whereas a
few cross the
subconjunctival tissue and
drain into conjunctival veins

16. • The episcleral veins drain
into the cavernous sinus
via the anterior ciliary and
superior ophthalmic veins,
• While the conjunctival veins
drain into superior
ophthalmic or facial veins
via the palpebral and
angular veins

17. SCLERALSPUR:
• Wedge shaped circular ridge.
• Pale, translucent narrow strip
of scleral tissue.
• Scleral spur is composed of a
group of fibres known as
“scleral roll”
• Scleral roll is composed of
75- 85% collagen and 5%
elastic tissue.

18. • ATTACHED:
Anteriorly:
trabecular meshwork
Posteriorly: sclera and
longitudinal fibers of
ciliary muscle

19. • Contraction of longitudinal ciliary
muscle opens up trabecular
spaces.
• Scleral spur prevents ciliary muscle
from causing Schlemm’s canal to
collapse.
• Individual scleral spur cells are
innervated by unmyelinated
axons.
• Varicose axons characteristic of
mechano-receptor nerve measure
stress in the scleral spur due to

20. CILIARYBAND:
• It marks the posterior most
part of the angle.
• Represents the anterior face
of ciliary body between its
attachment to the scleral
spur and insertion of iris.
• Width depends on the level
of iris insertion.
• Wide in myopes
• Narrow in hypermetropes.

21. • Ciliary band appears
as a grey/dark brown
band.
• It consists of longitudinal
fibres.
• The contraction of
longitudinal muscle, opens
the trabecular meshwork
and schlemm’s canal.

22. INNERVATION:
• Derives from the supraciliary nerve plexus and the
ciliary plexus in the region of scleral spur.
• Both sympathetic adrenergic and parasympathetic
and sensory innervation – present

23. Nerve endings contain mechanoreceptors
which are located in scleral spur :
act as proprioceptive tendon organs for the
ciliary muscle,
 contraction myofibroblast scleral spur cells
 baroreceptor function in response to change in
IOP

24. IMPORTANCEOFANGLEOFANTERIORCHAMBER:
• For classification of glaucoma
• To note the extent of neovascularization
• To assess angle recession
• History or evidence of inflammation
• For evidence of neoplastic activity
• Degenerative or developmental anomaly
• For planning of treatment – iris neovascularization
and laser procedure.

25. DIAGNOSTICMODALITIES:
1) Van-herick test
2) Flashlight/ pentorch test
3) Ultrasound biomicroscopy
4) Optical coherence
tomography (OCT)
5) Gonioscopy

26. 1) VAN-HERICKTEST:
• It is a slit lamp estimation of angle
• To perform this test, slit lamp is made very bright and thin. It
is offset 600 temporally to the slit lamp oculars. The
temporal sclera is illuminated and the slit lamp beam is
brought slowly towards the cornea until the anterior
chamber is first identified. The thickness of the cornea is
compared to the depth of the peripheral anterior chamber
• At, present, this test is most widely adopted
method for evaluating the ACA in community
optometric practice.

27. Corneal thickness: Chamber depth

28. GRADING:

29. 2) PENTORCHEXAMINATION:
• Depth of anterior chamber can be evaluated by focusing a
beam of light on the temporal limbus, parallel to the surface
of iris.
• In normal or deep AC the beam will pass through directly,
illuminating the opposite limbus.
• In shallow AC, the anterior placement of or bowing forward of
the iris obstruct the light and shadow is observed on the medial
half of iris.

30. 3) ULTRASOUNDBIOMICROSCOPY:
• UBM is a close contact (non-invasive) immersion technique.
• UBM is performed with the patient supine, positioning that
theoretically causes the iris diaphragm to fall back. This
deepens the anterior chamber and opens the angle.
• With UBM, only 1 quadrant can be imaged at a time.
• There is a risk of infection or corneal abrasion due to the
contact nature of the examination.

32. O
4) OPTICALCOHERENCE
TOMOGRAPHY(OCT)
• OCT is a non contact, non invasive
light based imaging modality.
• Provides image resolution higher
than that of UBM of anterior
segment in cross section with AS-
OCT, 4 quadrants can be scanned
at once(multiple cross- sectional
image of the anterior chamber
angle)
• The working principle of OCT is
similar to ultrasound which uses
echoes to locate structures within

33. 5) GONIOSCOPY:
• Gonioscopy is an essential diagnostic tool and examination
technique used to visualize the structures of the anterior
chamber angle.
• All gonioscopy lenses eliminate the tear-air interface by
placing a plastic or glass surface adjacent to the front of
the eye.
• Methods of gonioscopy:
1) Direct
2) Indirect

34. DIRECTGONIOSCOPY:Procedure
• Direct gonioscopy is most easily performed with the patient
supine and in the operating room for an examination under
anesthesia with 4% xylocaine.
• It is performed using a direct goniolens and either a
binocular microscope or a slit-pen light.
• The lens is positioned after saline or viscoelastic is placed on
the eye, which can act as a coupling device.
• The lens provides direct visualization of the chamber angle in an
erect position

35. DIRECTGONIOSCOPY:
• Direct
goniolenses:
Koeppe Barkan
Swan-Jacob

36. KOEPPELENS:
• Koeppe lens is the prototypical
diagnostic goniolens
• Koeppe gonioscopy is an
unsurpassed method for viewing the
chamber angle in the operating
room.

37. • Koeppe-type lenses are also quite useful for performing
funduscopy.
• When used with a direct ophthalmoscope and a high-plus-
power lens, they can provide a good view of the fundus, even
through a very small pupil.
• These lenses are especially helpful in individuals with
nystagmus or irregular corneas.
• Inconvenience is the major disadvantage of the direct
gonioscopy systems.

38. • BARKAN’S LENS:
The Barkan goniolens has served as the
prototypical surgical goniolens for surgical
goniotomy. Has no rod
• SWAN-JACOB LENS:
The Swan-Jacob goniolens has been modified for
goniosurgery and is now one of the most popular
models for angle surgery.

39. ADVANTAGES-DirectGonioscopy:
• Observer’s height can be changed to look deep or get a better
look at the angle structure’s
• As it is done in supine position it can be used for sedated,
comatosed patients and in children
• Useful in examining the fundus with small pupil
• Straight on the view
• Panoramic view of the angle structure’s
• Comparison of angle recession
• Causes less distortion of AC

40. DISADVANTAGES:
• Inconvinient
• Special equipment is
needed.

41. INDIRECTGONIOSCOPY:Procedure
• Indirect Gonioscopy is performed under the slit lamp.
• The patient and the examiner must be positioned in a comfortable
fashion.
• A drop of topical anesthetic is then applied to the conjunctiva of both
eyes.
• If using the Goldmann lens, contact gel is placed in the concave part
of the lens.
• If using a Posner or similar type lens, a drop of artificial tears can be
placed on the concave surface.
• The patient is then asked to open both eyes and look upwards.
• The examiner can then pull down slightly on the lower lid and
places the lens on the surface of the eye.

42. • The patient is then asked to look straight ahead.
• Most examiners choose to start with the inferior angle as it is
usually more open, and the pigmentation of the trabecular
meshwork is slightly more prominent, allowing for easier
identification of the angle structures.
• Continue identifying all angle structures in all 4 quadrants, and
then repeat with the other eye.

43. INDIRECTGONIOSCOPY:
• Indirect
goniolenses:
Goldmann
Zeiss
Sussm
an
Posner

44. GOLDMANNLENS:
• It is a three mirror contact
lens
• For examination of the
entire ocular fundus and
the iridocorneal angle.
• The advantage of a longer
mirror is that it often permits
binocular observation of the
lateral sections of the ocular
fundus

45. OBSERVATION:
• Central lens(1) - Posterior
pole
• 730 mirror(2) - Equator
• 670 mirror(3) - Ora serrata
• 590 mirror(4) - Iridocorneal
angle

46. ZEISSGONIOLENS:
• 4 identical mirrors angled at 640 which
allow examination without rotation of the
lens
• ADVANTAGE: Coupling material not
required as the posterior curvature of the
lens is equal t the corneal curvature
• Easy to perform when mastered
• Indentation gonioscopy can be performed
• DISADVANTAGE: difficult to master
• Does not stabilize the globe

47. •SUSSMAN LENS:
It is similar to Zeiss Lens except that it has no
handle
•POSNER LENS:
It is a modified Zeiss Lens with a handle

48. ADVANTAGES-IndirectGonioscopy:
• Preferred by most
• Quick, convenient
• No special equipment needed
• Slit lamp is used, which provides
variable magnification and
illumination
• Can create corneal wedge
• Allows differentiation of appositional
and synechial angle closure

49. DISADVANTAGES:
• Mirror image can be confusing
• Inadvertent pressure on the cornea:
 exaggerates the degree of angle narrowing in the
Goldmann lens
 opens the angle in four mirror lenses

50. GRADINGSYSTEMS:

53. REFERENCES:
• Glaucoma, 6th edition, Comprehensive Ophthalmology, A K
Khurana.
• Gross and Microanatomy of Angle of the Anterior Chamber,
Glaucoma, Volume 1, 3rd edition, Modern Ophthalmology, L C
Dutta and Nitin K Dutta.
• Parsons’ Diseases of the Eye, 22nd edition.
• Shield’s textbook of Glaucoma, 8th edition.