GONIOSCOPYMADE BY : SWATI PANARA

FROM : BHARTIMAIYA COLLEGE OF OPTOMETRY

2nd YEAR 4th SEMESTER

INTROUCTION

• THE TERM GONIOSCOPY WAS COINED BY TRANTAS IN 1907.

• IT IS A CLINICAL TECHNIQUE THAT IS USED TO EXAMINE STRUCTURE IN THE ANTERIOR CHAMBER ANGLE.

PURPOSE OF GONIOSCOPY

• WHY DO I NEED PERFORM GONIOSCOPY ?? - fundamental part of comprehensive exam. - done initially for all glaucoma patient and

suspects. - repeated periodically for patients with angle

closure glaucoma.

• WHAT CAN I ACHIEVE WITH GONIOSCOPY ?? - Visualization of anterior chamber angle - view of the peripheral iris - differentiation between angle closure ,

occludable and secondary glaucoma.

• WHAT SHOULD I LOOK FOR IN GONIOSCOPY ? - level of iris insertion - shape and profile of peripheral iris - estimated width of the angle approach - degree of trabecular pigmentation - areas of iridotrabecular apposition

PRINCIPLE• The total internal reflection at the cornea occurs

because the angle of incidence of the rays from the anterior chamber angle structure is greater than the critical angle of the cornea – air interface , which is approximately 46°

TYPES

DIRECT GONIOSCOPE

INDIRECT

GONIOSCOPE

DIRECT GONIOSCOPY

• It is performed with a steep convex lens which permits light from the angle to exit the eye closer to the perpendicular at the lens – air interface.

• These lenses are used with a operating microscope.

• Direct gonioscopy is useful but fairly impractical for routine use.

TYPES

Koeppe goniolens

Huskins barkan’s lens

Swan Jacob's lens

Richardson- Shaffer's lens

Sieback goniolens

Worth goniolens

KOEEPE LENS

• It is the most commonly used for diagnostic direct gonioscopy.

HUSKINS BARKAN’S LENS• It is a prototype surgical goniolens used for

goniotomy.

SWAN JACOB’S LENS• It is also used for surgical purpose..

SIEBACK GONIOLENS• It is a tiny goniolens which floats on the cornea.

RICHARDSON – SHAFFER’S LENS

• It is basically a small Koeppe lens used for infants.

WORTH GONIOLENS• It anchors to cornea by partial vacuum.•

TECHNIQUE

• Cornea is first anaesthetized with 4% xylocaine instilled topically.

• Ideal position – patient lying supine with the examiner sitting on the side of the eye.

• Patient looking up , lower lip of the goniolens is inserted below the lower lid.

• Patient is asked to look down and upper lip is placed beneath upper lid.

• Now the patient’s head turned towards the examiner , the nasal lip of goniolens is slightly raised and normal saline drops are used for irrigation

• Now gonioscopy is performed with the patient looking to the ceiling.

ADVANTAGE

• Greater flexibility• Used in goniotomy surgery• Used in anaesthetized patients as in infants• Causes lesser distortion of anterior chamber• angle becomes deep in supine position so it is

easy to see the angle.• Panoramic view is obtained so one part of

angle could be compared with the other.

• Using two lenses , both eyes can be examined simultaneously.

• Provide a straight view rather than inverted view.

• Detailed examination of minor structure is possible.

DISADVANTAGE

• Inconvenient• Annoying light reflex from cornea• Time – consuming• Benefits of slit lamp are not available

INDIRECT GONIOSCOPY

• Indirect gonioscopy uses mirrors or prism to over come the problem of total internal reflection.

• Moreover , it uses the slit lamp’s illumination and magnification system to its advantage.

TYPES

GONIOPRISM

REQUIRING COUPLING

AGENT

GONIOPRISM NOT

REQUIRING COUPLING

AGENT

GONIOPRISM REQUIRING COUPLING AGENT

GOLDMANN THREE MIRROR GONIOPRISM

GOLDMANN TWO MIRROR GONIOPRISM

GOLDMANN SINGLE MIRROR

GONIOPRISM

ALLEN – THROPE GONIOPRISM

GOLDMANN THREE MIRROR GONIOPRISM

• The mirror having inclination of 59° and domed upper border is used for gonioscopy.

• (1) the mirror inclined at 67° is used to examine pars plana area of ciliary body.

• (2) the mirror having inclination of 73° is used to examine ora serrata area of peripheral fundus.

GOLDMANN TWO MIRROR GONIOPRISM

• Both the mirrors are inclined at 62°• It need to be rotated once to examine the

whole angle.• Laser trabeculoplasty

GOLDMANN SINGLE MIRROR GONIOPRISM

• The mirror is inclined at 62°• It is prototype diagnostic gonioprism.• It is to be rotated three times to examine the

whole angle.

ADVANTAGE OF GOLDMANN GONIOPRISM

• Easy to use• Excellent view• Stabilizes the globe and there for can be used

in argon laser trabeculoplasty.• Peripheral retina can be seen• Goldman two mirror gives best In – situ view

of the angle.

DISADVANTAGE OF GOLDMANN GONIOPRISM

• Curvature of lens is more than that of cornea so a coupling material is required. it blurs vision and fundus therefore field charting , direct and indirect ophthalmoscopy cannot be done immediately after its use.

• It cannot be used for indentation gonioscopy.• Only one mirror is there for gonioscopy so it

needs to rotated by 360°

ALLEN – THROPE GONIOPRISM

• It has got four prisms instead of mirror and allows examination of the whole angle without rotating the prisms.

GONIOPRISM NOT REQUIRING COUPLING AGENT

ZEISS FOUR MIRROR

GONIOPRISM

POSNER GONIOPRISM

SUSSMAN LENS

TOKEL GONIOPRISM

ZEISS FOUR MIRROR GONIOPRISM

• Four identical mirrors angled at 64° which allow examination without rotation of the lens.

• ADVANTAGE : coupling material not required• Easy to perform when mastered• Indentation gonioscopy can be performed• DISADVANTAGE : difficult to master• Does not stabilize the globe

POSNER LENS

• It is similar to zeiss gonioprism but is made of plastic instead of glass and also has fixed rather than detachable handle.

TOKEL GONIOPRISM

• It is a single mirror gonioprism and has got a wider field of view.

• SUSSMAN LENS• It is also similar to zeiss lens except that it has

no handle.

TECHNIQUE

• Eye is anaesthetized with the topical anaesthetic anent

• Patient who is sitting on the slit lamp is asked to look down

• The thumb of one hand is used to retract the upper lid.

• The lower edge of the gonioscope is placed on the lower lid.

• Slit lamp beam is focused on the mirror that shows the angle diametrically opposite to it.

ADVANTAGE

• Easier to learn.• Faster to perform.• Requires less instrumentation and space.• Slit lamp provides better optics and lighting.• Indentation gonioscopy can also be done.• Magnified stereoscopic view of optic disc can

also be obtained.

DISADVANTAGE

• Comparison is not possible.• Limited positioning of light rays.• Difficult to perform in horizontal meridian.• Mirror image seen , so confusing.• Excessive pressure may open or close the

angle artefactually.

RECORDING

• Most posterior angle structure observed.• Angular approach at the recess.• Iris contour• Amount of pigment• to what degree the angle opens with

indentation• Surgical alteration such as sclerectomy and

peripheral iridotomy.

GRADING SYSTEM FOR THE ANGLE OF ANTERIOR CHAMBER

SCHEIE’S GRADING

SHAFFER’S GRADING

RP CENTRE GONIOSCOPIC

GRADING

Speath GONIOSCOPIC

GRADING

SCHEIE’S GRADING

• Grade 1 narrow = hard to see over iris root into recess

• Grade 2 narrow = ciliary body band obscured• Grade 3 narrow = posterior trabeculum

obscured• Grade 4 narrow = only schwalbe’s line visible.

SHAFFER’S GRADING SYSTEM

• Grade 0 —PARTIAL OR COMPLETE CLOSURE

• Grade I </= 10° angle of approach

• Grade II -20° angle of approach

• Grade III 20°–35° angle of approach

• Grade IV 35°–45° angle of approach

RP CENTRE GONIOSCOPIC GRADING• Grade 0 = no dipping of the beam• Grade 1 = dipping of the beam• Grade 2 = schwalbe’s line and anterior one –

third of the trabecular meshwork visualized.• Grade 3 = middle one – third of trabecular

meshwork visualized.• Grade 4 = posterior one – third of trabecular

meshwork• Grade 5 = scleral spur visualized• Grade 6 = ciliary body band visualized

SPEATH CLASSIFICATION

GONIOSCOPIC VIEW OF ANGLE STRUCTURE

SCHWALBE’S LINE

• Termination of descement’s membrane• It is marked only by a slight change in colour

from trabecular meshwork or by a faint white line.

• Important landmark in identifying the gonioscopic anatomy in confusing angle.

TRABECULAR MESHWORK

• It has an anterior non pigmented trabecular meshwork and posterior pigmented trabecular meshwork.

CILIARY BODY BAND

• It is light grey or dark brown just posterior to the scleral spur.

ROOT OF IRIS

• Iris contour is slightly convex or flat.• Colour varies in different individuals.

GONIOSCOPIC TECHNIQUE

GONIOSCOPIC IN SITU MANIPULATIVE GONIOSCOPY

INDENTATION GONIOSCOPY

CLINICAL USE OF GONIOSCOPY

• Differentiation between primary open angle glaucoma and primary closure angle glaucoma

• To diagnose and provide a prognosis for the congenital glaucoma.

• To diagnose secondary glaucoma and unusual causes of glaucoma.

• For treatment• To diagnose condition like tumours of anterior

segment , intraocular foreign body.

LIMITATION

• Cannot be performed in painful inflamed eyes.• Difficult to perform in case of acute glaucoma

where eyes are painful.

REFERENCE• CLINICAL PROCEDURE IN PRIMARY EYE CARE –

DAVID B. ELLIOTT• OPTIC AND REFRACTION – A K KHURANA• NET• PURAB SIR’S NOTES• COMPREHENSIVE OPHTHALMOLOGY – A K

KHURANA• KANSKI

THANK YOU