Gonioscopy allows visualization of the anterior chamber angle to evaluate for angle closure and diagnose glaucoma. It was pioneered in the early 20th century with the introduction of contact lenses to eliminate total internal reflection at the cornea. Direct gonioscopy uses contact lenses for a straight view, while indirect gonioscopy uses prisms for an inverted image at the slit lamp. Examination of angle structures like the trabecular meshwork and classification systems help diagnose angle closure and glaucoma. Gonioscopy is used for diagnostic and therapeutic purposes like laser and surgery.

1. GONIOSCOPY
BY Dr. ASHISH GUPTA
MODERATOR - Dr. ANAMIKA TIWARI

2. HISTORY
TRANTAS (1907) :-
First to examine angle in the
keratoglobus eye and introduced the
term GONIOSCOPY.
SALSMANN (1914) :-
Introduced the goniolense to observe
the angle.

3.  GOLDMANN (1938) :- Introduced the
gonioprism.
 BARKAN :- Established the use of Gonioscopy
in management of Glaucoma.

4. CONCEPT OF GONIOSCOPY
Angle of anterior chamber
cannot be visualized
directly through an intact
cornea because light
emitted from angle
structures undergoes
total internal reflection.

5. Goniolenses eliminates
the total internal reflection by
replacing the cornea- air
interface by a new interface,
which has a refractive index
greater than that of cornea and
tears.

6. METHODS OF GONIOSCOPY
 1. DIRECT GONIOSCOPY
 2. INDIRECT GONIOSCOPY
- WITHOUT INDENTATION
- WITH INDENTATION

7. DIRECT GONIOSCOPY
 ANTERIOR curve of goniolense is such that the critical
angle is not reached and the light rays are
REFRACTED at contact lens-air surface.
 Provide a direct view of the angle. They do not require a
slit lamp & are used with in supine position.

8. DIRECT GONIOLENSES:
1. Koeppe goniolense
2. Richardson-shaffer
3. Huskins Barkan
4. Sieback
5. Swan jacob
6. Layden

9. KOEPPE GONIOLENS :-
 It is most commonly used for diagnostic direct
gonioscopy. It is easy to use & provides a
panoramic view of the angle.

10.  Richardson-Shaffer’s goniolens - It is basically a small
Koeppe lens used for
infants.
 Worth goniolens - It anchors to cornea by partial
vacuum.
 Sieback goniolens - It is a tiny goniolens which floats on
cornea.
 Huskins Barkans lens - It is the prototype surgical
goniolens used for goniotomy.

11. TECHNIQUE OF DIRECT GONIOSCOPY
 Patient lies supine with examiner sitting on the side of
the eye to be examined.
 After topical anesthesia, goniolens is positioned on
the cornea, using balanced salt solution or methyl
cellulose.
 Examiner holds the goniolense in one hand and the
light source in other and scans the anterior chamber
angle by shifting his or her position until all 360
degrees have been studied.

12. TECHNIQUE OF DIRECT GONIOSCOPY

13. ADVANTAGES-
 Greater flexibility as position of observer can be
changed.
 Panoramic view is obtained so one part of the
angle can be compared with other.
 Angle deep in supine position so it is easy to see
the angle.
 Can be used in sedated patient and also in infants.
 Provides a straight view rather than inverted view.

14. DISADVANTAGES:-
 Annoying light reflexes from cornea.
 Time consuming.
 Benefits of slit-lamp like variable
light & better clarity are not available.

15. INDIRECT GONIOSCOPY
 The light rays are REFLECTED by mirror in the contact
lense (gonioprism).
 Provide a mirror image of the opposite angle & used
in conjunction with a slit lamp.

16. INDIRECT GONIOSCOPY
Two types :-
1. Non indentation
2. Indentation

17. 1. NON INDENTATION GONIOSCOPY .
TECHNIQUE
 After anaesthetising the cornea, the coupling gel
is inserted into the cup of the goniolens.
 goniolense is placed and tipped onto the
cornea.
 Slit-lamp beam is focused on the mirror which
shows the inverted angle image.

19. GONIOPRISMS (NON INDENTATION) -
Surface is slightly larger than cornea & require a
coupling gel.
1.Goldmann single mirror
2.Goldmann-3 mirror
3.Allen-Thorpe

20. GOLDMANN MIRRORS
GOLDMANN SINGLE MIRROR GOLDMANN 3 MIRROR

21. 2. INDENTATION GONIOSCOPY
 Varying amount of pressure applied to the cornea with a tear
coupled indirect contact lens.
 Examiner observes the effect on angle width.
 Increased pressure indents the central cornea & displaces
fluid into the angle, opening it wider.

22. GONIOPRISMS (INDENTATION) -
1. Zeiss four mirror
2. Sussmman four mirror
3. Tokel single mirror
4. Posner four mirror

23. 1. ZEISS -4 MIRROR GONIOPRISM -
-It has four identical mirrors angled at 64° which allow
examination of the four quadrants without rotation of
the lens.
-The contact surface of lens has a 9mm diameter.

24. 2. SUSSMMAN LENS :- It is also similar to Zeiss
lense except it has no handle.

25. 3.TOKEL GONIOLENS :- It is a single mirror goniolens
& has got a wider field of view.
4.POSNER GONIOLENS:- It is similar to Zeiss-goniolens
but it is made of plastic & also
has a fixed handle.

26. ADVANTAGE OF INDIRECT GONIOSCOPY:-
 Easy to perform when mastered
 All four quadrants can be seen when four mirror
lense used.
 With slit lamp, variable magnification and
illumination can be achieved.
 Indentation Gonioscopy can be performed, which
allows differentiation of appositional and synachial
angle closure.
 Coupling agent is not used, so visualization of
fundus & photography is possible.

27.  DISADVANTAGE-
 Difficult to master.
 Mirror image can be confusing.
 May open the angle artefactually if pressure applied.

28. GONIOSCOPIC VIEW OF ANGLE STRUCTURES

29. 1. SCHWALBE’S LINE:-
 Most anterior structure
 Irregular elevation of 50 to 100 µm width.
 Peripheral termination of cornea where the Descemet’s
membrane ends.

30.  Marked only by a slight change in colour from
trabecular meshwork or by a faint white line.
 Best identified by locating the “Corneal Wedge”.

31. 2. TRABECULAR MESHWORK :-
- It lies between the Schwalbe’s line anteriorly & scleral
spur posteriorly and has an average width of 600 µm.
- Smooth in infants but becomes coarse and pigmented
with age.

32.  The posterior functional pigmented part has a greyish-
blue translucent appearance.
 This posterior portion overlies the canal of Schlemm,
from where aqueous humour escapes from the anterior
chamber.
 Anterior part is non-functional and non-pigmented.

33. 3. SCLERAL SPUR:-
- Anterior most projection of the sclera
- Situated just posterior to the TM and appears as a narrow,
dense, often shiny, whitish, band.
-May be obscured by iris process, and pigments.

34. 4. CILIARY BODY BAND:-
-Lies just behind the scleral spur as a pink to dull brown or
slate grey band.
-Portion of ciliary body which is visible in the angle as a
result of insertion of the iris into the ciliary body.

35. 5. ROOT OF IRIS :-
 Iris contour is slightly convex or flat
 colour varies in different individuals
 Radial marking and crypts are present

36. OTHER STRUCTURES
IRIS PROCESSES:-
 Normal variants
 Appear as fine strands extending from iris to the scleral
spur.
 These do not inhibit the
movement of the iris during
indentation Gonioscopy.

37. ANGLE CLASSIFICATION
1. SCHEIE’S GRADING:-
It is based on the extent of visible angle structure as :-
 WIDE OPEN - all structures visible
 GRADE I - hard to see over iris root into recess.
 GRADE II - Ciliary body band obscured.
 GRADE III - posterior trabeculum obscured.
 GRADE IV - Only Schwalbe’s line visible.

38. 2. SHAFFER’S GRADING:-
 Estimation of the angle width is achieved by observing
the angle between two imaginary lines, constructed
tangential to inner surface of trabeculum and the
anterior iris surface.

39. GradeGrade AngleAngle
widthwidth
ConfigurationConfiguration ChancesChances
of Closureof Closure
Structures visibleStructures visible
on gonioscopyon gonioscopy
IVIV 35-45°35-45° Wide openWide open NilNil From SchwalbeFrom Schwalbe’’s lines line
to ciliary bodyto ciliary body
IIIIII 20-35°20-35° Open angleOpen angle NilNil From SchwalbeFrom Schwalbe’’s lines line
to scleral spurto scleral spur
IIII 20°20° ModeratelyModerately
narrownarrow
possiblepossible From SchwalbeFrom Schwalbe’’s lines line
to TMto TM
II 10°10° Very narrowVery narrow HighHigh SchwalbeSchwalbe’’s line onlys line only
OO 0°0° closedclosed ClosedClosed No angle structureNo angle structure
visiblevisible

40. 3.SPAETH CLASSIFICATION:-
This classification elaborated a complex grading system
that captures a detailed three dimensional information
in coded form.


41. A- Anterior to trabecular meshwork.
(Schwalbe’s line)
B- Behind Schwalbe’s lines (at the
level of Trabecular meshwork).
C- Centered at the level of scleral
spur.
D- Deep to scleral spur (ant. Ciliary
body)
E- Extremely deep in the ciliary body

42. CLINICAL USES OF GONIOSCOPY
DIAGNOSTIC
 Differentiation between POAG and PACG
 To diagnose secondary glaucomas
 Angle recession.
 Uveitic glaucoma. Etc..
 Diagnose Tumours of anterior segment
 Early detection of KF Ring.

43. THERAPEUTIC -
 To perform argon laser trabeculoplasty
 Laser iridoplasty
 Laser sclerostomy
 Goniotomy & trabeculotomy

44. LIMITATIONS OF GONIOSCOPY
 Can not be performed in painful inflamed eyes.
 Can not be performed under mydriasis.
 Hyphaema
 Compromised cornea
 Lacerated or perforated globe
 COMPLICATION- Corneal abrasion.

45. GONIOSCOPY: PATHOLOGICAL CONDITIONS
ANGLE CLOSURE GLAUCOMA
 The angle is first occluded appositionally, followed
by a sticky adhesion & later on by peripheral ant.
synechiae over wide area.
.

46. PERIPHERAL ANTERIOR SYNECHIAE
 Not pathognomonic of any single disease entity
 Tend to form first
 Superiorly - Angle closure glaucoma
 Inferiorly – Uveitis
 Anywhere –post traumatic cases

48. PLATEAU IRIS CONFIGURATION
 Iris appears to be in plane to intersect with Schwalbes
line, a steep drop off occurs immediately before TM
 Potential for causing ACG
 Anteriorly positioned ciliary process

49.  On Indentation Gonioscopy -TM is visible & peripheral
hump can be seen in iris which is called
sine wave appearance.

50. PIGMENTARY GLAUCOMA
- Heavy pigment dispersion in Trabecular meshwork.
- Typical patients are young myopic males.

51. NEOVASCULAR GLAUCOMA
 New vessel formatiom occurs on iris known as RUBIOSIS
IRIDIS, which is frequently associated with severe form of
glaucoma, known as NEOVESCULAR GLAUCOMA.

52. PSEUDOEXFOLIATION GLAUCOMA
PXS Associated with Excessive pigment dispersion
which leads to increased pigmentation of trabecular
meshwork and schwalbe’s line (Sampaolesi’s line).

53. POSTERIOR EMBRYOTOXONE AXENFELE ANOMALY
AXENFELD ANOMALY

54. ANGLE RECESSION
Irregular widening of ciliary body band occurs sometimes
following trauma to the eye. It occurs due to tear between
longitudenal and circular muscles of cilliary body.

55. MISCELLENIOUS GONIOSCOPIC FINDINGS
IRIS MELANOMA LENSE HEPTIC


56. NEWER WAYs TO EVALUATE ANTERIOR
CHAMBER ANGLE

57. REFERENCE
S Textbook of glaucoma – M.Bruce Shields 5th
edition .
 Becker-Shaffer's, Diagnosis and therapy of Glaucoma 7th
edition.
 Jack J. Kanski, Clinical Ophthalmology 7th
edition.
 A.K. Khurana, Comprehensive ophthalmology.
 www.gonioscopy.org a website dedicated to gonioscopy -video atlas