Gonioscopy

GONIOSCOPYDr. Rashmi Ranjan

Greek : gṓ nḗ : angle , Ộs’k-pḗ : view

Alexois Trantas:(1907) First visualized angle in an eye

with Keratoglobus

Maximilian Salsmann:(1914) Father of Gonioscopy. First

introduced Goniolens

HISTORY

Koeppe : Designed improved Contact lens and gave the

method biomicroscopy of angle of anterior Chamber with slit lamp.

Manuel Uribe Troncoso: Developed Gonioscope for magnification &

illumination of Angle. First to write a Comprehensive book on

Gonioscopy

Otto Barkan: Established use of Gonioscopy

in Management of Glaucoma.

Goldmann:(1938) Introduced Gonioprism.

Critical Angle: Cornea Air Interface~46degree Light rays from Angle exceeds Critical angle so rays reflected

back into AC,preventing direct visualisation of Angle

PRINCIPLE

PRINCIPLEINDIRECT DIRECT

LENS DESCRIPTIONKOEPPE Prototype Diagnostic LensRICHARDSON SHAFFER Small Koeppe Lens used for

InfantsLAYDEN For Gonioscopic Examination

of Premature InfantsBARKAN Prototype Surgical GoniolensTHORPE Surgical & Diagnostic lens for

Operating RoomsSWAN JACOB Surgical Goniolens used in

Children

CONTACT LENSES FOR GONIOSCOPYDIRECT

Used with Handheld Biomicroscope (15x to 20x) with separate light source

KOEPPE

BARKAN

SWAN JACOB

LENS DESCRIPTIONGOLDMANN SINGLE MIRROR Mirror inclined at 62 degreesGOLDMANN THREE MIRROR One mirror for gonioscopy, two for

retina; coated front surface for laser useZEISS FOUR MIRROR All 4 mirrors inclined at 64 degrees for

gonio;requires holder;fluid bridge not required.

POSNER FOUR MIRROR Modified Zeiss four mirror gonioprism with attached handle

SUSSMAN FOUR MIRROR Handheld Zeiss type GonioprismTHORPE FOUR MIRROR Four gonioscopy mirrors; inclined at 62

degrees;requires fluid bridgeRITCH TRABECULOPLASTY LENS

Four gonioscopy mirrors; two inclined at 59 degrees & two at 62 degrees with convex lens over two

LATINA TRABECULOPLASTY LENS

One mirror for Trabeculoplasty

INDIRECT

GOLDMANN SINGLE MIRROR

GOLDMANN THREE MIRROR

All 4 mirrors inclined at 64 degrees for gonio

ZEISS FOUR MIRROR

POSNER FOUR MIRROR

HandheldSUSSMAN FOUR MIRROR

Four gonioscopy mirrors; inclined at 62 degrees;requires fluid bridge

THORPE FOUR MIRROR

RITCH TRABECULOPLASTY LENS

One mirror for Trabeculoplasty

LATINA TRABECULOPLASTY LENS

INDIRECT TECHNIQUE

DIRECT

ADVANTAGE DISADVANTAGE

Observer’s height can be changed

Done on sedated, comatosed & Children

Panoramic view of Angle Less distortion of AC Useful in examining fundus

with small pupil

Inconvinient Special equipments required Difficult to master Does not Stabilize globe

INDIRECTADVANTAGE DISADVANTAGE

Quick & Convinient No special equipment

required Allows differentiation B/w

Appositional & Synechial closure

Can create corneal wedge

Inadverent Pressure on Cornea

Mirror image is confusing

DIRECT V/S INDIRECTDIRECT INDIRECT

Panoramic view of iridocorneal angle with ability to adjust view by examiner.

Both eyes can be examined simultaneously.

No viscous [ coupling ] material required.

Direct view for surgery e.g. Goniotomy

DISADV: Inability to perform indentation, low magnification, assistance.

Segmental View

One Eye at a time

Viscous required

Mirror Image seen Excellent optics with Slit

Lamp Indentation Can be Done

Classification : Open or Closed angle glaucoma To assess AC angle recess & risk of angle closure. To identify plateau iris. To look for Abnormal angle pigmenatation, PEX , angle recession, cyclodialysis, foreign body, Neoplasm, copper deposition , blood in Schlemm’s canal.

INDICATIONSDIAGNOSTIC

Evaluation of trabeculectomy fistula , glaucoma drainage devices

Congenital anomalies- aniridia, iris processes.

Laser trabeculosplasty/ goniophtocoagulation

Goniotomy/ Gonioplasty/ Trabectome sxReopening of blocked trabeculectomy

opening.Laser of suture around tube of G.D.D.Indentaion Gonioscopy to break an attack

of Ac. ACG

THERAPEUTIC

NORMAL ANGLE STRUCTURES

This structural portion of ciliary body is visible in the A.C. as a result of iris insertion into ciliary body

Width depends on level of iris insertion

Wider in myopes and narrow in hyperopia

Color: grey to dark brown

CILIARY BODY BAND

This is the post. Lip of scleral sulcus which is attached to the ciliary body posteriorly and corneo-scleral meshwork anteriorly

Color : prominent white line

SCLERAL SPUR

Pigmented band anterior to scleral spur Although extent of TMW is from root of iris to

schwalbe’s line it is considered as 2 portions

a) Anterior - between schwalbe’s line and ant. Edge of schlemm’s cannal

Involved in lesser degree of aqueous out flowb) Posterior – Functional part , primary site of aqueous out

flow Appearance of funtional TMW depends on

amount of pigment deposition

TRABECULAR MESHWORK

At birth no pigment and with age from faint to dark brown

Pigment deposition may be homogeneous or irregular

When lightly pigmented blood reflex in schlemm’s cannal may be seen as a red band

TRABECULAR MESHWORK

When a thin slit of light hits the irido-corneal angle at an angle of 10 -15 , two light reflections are seen from ⁰ ⁰the external and internal corneal surfaces which pipe down at the sclero-corneal junction (Schwalbe’s line) marking the anterior border of trabecular meshwork.

Corneal wedge is a useful technique to identify the trabecular meshwork in eyes that are either nonpigmented or excessively pigmented its diff. to mark trabecular meshwork begins

CORNEAL WEDGE

SCHWALBE LINE Junction between

anterior chamber angle structures and cornea where the descement’s membrane terminates

Fine ridge ant. to TMW identified by a small built up of pigment

Landmark for TMW in narrow angle

SAMPAOLESI'S LINE

POSTERIOR EMBRYOTOXON

Contour

Flat- Deep AC Concave- Shallow AC , Hyperopia Convex- High Myopia, Pigment Dispersion Syndrome Abnormal Rolling- Plateau iris

IRIS

IRIS PROCESS PAS

Fine Extend into scleral Spur Follow concavity of Recess Underlying Structures are

seen Iris moves with indentation Broken with angle

Recession

Broad Extend Beyond Scleral Spur Bridge concavity of Recess Obscures the View Resists Movement Intact in Recession

ANGLE BLOOD VESSELS

NORMAL NEOVASCULARIZATION

Radial Orientation Thick Non Branching Do not cross Scleral Spur

Fine Arborising Crosses Scleral Spur

MANUPULATIVE GONIOSCOPY Over the Hill Corneal Wedging Indentation

It’s a special maneuver to view over a steep iris.

It is done by asking the patient to look in the direction of the mirror or moving the mirror towards the angle being viewed

OVER THE HILL/DIVE BOMBER’S VIEW

INDENTATION GONIOSCOPY When iris covers the trabecular meshwork

(TM) its easy to mistake:◦The non-pigmented TM for scleral spur◦Pigmented Schwalbe’s line for TM◦Apposition from synechiae

Indentation Gonioscopy is particularly useful in these cases

Useful when iris surface is convex◦Done when recognition of angle structures is

difficult Performed in all glaucoma cases

◦Differentiates appositional vs synechial closure in pupillary block

◦Measures extent of angle closure◦Identifies plateau iris config.◦Identifies lens induced angle closure

INDENTATION:PLATAEU IRIS

If posterior [ pigmented ] part of trabecular meshwork is not visible in more than 180 degrees of angle without indentation or manipulation, this is known as an ‘ occludable angle’.

OCCLUDABLE ANGLE

SCHEMATIC REPRESENTATION OF GONIOSCOPIC FINDINGS

SCHEIE SYSTEM: most posterior structure visible. SHAFFER’S SYSTEM : assess geometric angle width in 4 grades . angle potential for occlusion. SPAETH SYSTEM : three dimentional structure of angle - level of iris insertion and peripheral iris

configuration. RPC GRADING

GRADING

GRADE STRUCTURE SEEN PROBABILITY

0 CBB Seen No angle closure

I CBB Narrow No angle closure

II CBB not seen, SS Seen Rarely closure possible

III Posterior TM Not seen Closure likely

IV Schwalbe’s Line not seen Gonioscopicaly closed

SCHEIE SYSTEM

SHAFFER’S SYSTEM

Angular width Iris Configuration Level of Iris Insertion Iris Processes Pigmentation of posterior Trabecular

Meshwork

SPAETH SYSTEM

SPAETH SYSTEM

SPAETH SYSTEMIRIS PROCESSES PIGMENTATION OF TBM

U – along angle recess

V – upto trabecular meshwork

W – upto Scwalbe’s Line

0 no pigmentation 1+ just perceptible 2+ definite but mild 3+ moderately dense 4+ dense black pigmentation

GRADE STRUCTURE SEEN

0 CLOSED

1 SCHWALBE’S LINE

2 ANTERIOR(NON PIGMENTED) TM

3 POSTERIOR PIGMENTED TM

4 SCLERAL SPUR

5 CILIARY BODY BAND

6 ROOT OF IRIS

RPC System of Grading

Angle is Deep Flat Iris inserted posterior to Scleral Spur Translucent Trabecular Meshwork Normal CBB

In Congenital Glaucoma: Anterior insertion of iris directly on TBM Thin CBB Congenital vessels in ‘’Hair Pin’’ Configuration

ANGLES IN INFANTS

ANGLE ANOMALIES

CLOSED ANGLE

FOREIGN BODY IN ANGLE

PIGMENTARY GLAUCOMA

IOL HAPTIC IN ANGLE

HYPHEMA

CYCLODIALYSIS

DRAINAGE IMPLANT

IRIS MELANOMA

IRIS NEVUS

Wash with soap & water Soaking the lens for 5-10 min in fresh solution of Sod.

Hypochlorite [ 1:10 household bleach : water] Rinsing with sterile water Air drying 3% H2O2 or 1% Formaldehyde can also be used. Direct surgical gonioscopes [ Koeppe, Swan Jacob] can

be sterilized with ethylene oxide.

STERILIZATION & DISINFECTION

Contact investigation patient discomfort. Conjunctival infection. Artefactual angle closure Slit lamp illumination-> pupil constriction-> opens up

the angle Wide interobserver variations. Indentation corneal folds, distorted view of angle

structures, epithelial injury.

LIMITATIONS

Painful inflamed eye

Acute glaucoma with edematous cornea

Mydriatic drugs- obscure angle by bunching up iris

Suspected open globe injury or early in course of suspected closed globe injury with hyphaema as pressure may precipitate rebleed.

CONTRAINDICATION

OTHER IMAGING MODALITIES

High Frequency (50 – 100 Mhz)B Scan system

Ocular structures anterior to Pars Plana

Lateral Resolution 50mm Axial Resolution 25mm Depth of penetration 4-5mm Field of View 4x4mm

ULTRASOUND BIOMICROSCOPY

PUPILLARY BLOCK

High Resolution Anterior Segment Imaging Modality

Spatial Resolution of 10-20µm Uses 1310 nm of Infra Red light Works on Principle of Low

Coherence Interferometry Measures: Echotime delay &

Intensity of Back Scattered light & Back Reflected Light

Anterior Segment OCT

APPLICATIONS Imaging of Anterior Chamber Evaluation of Structural Causes of Angle

Closure Effects of Interventions like Iridotomy Imaging of Trabeculectomy Blebs Tube Position in Glaucoma Drainage Implants Angle Assesment in Corneal Opacities Pachymetry Large Scale Screening of Angle Closure &

Angle Closure Glaucoma

Anterior Synechiae

AS OCT UBM

Non Contact Axial Resolution 10-20µm Light Energy 90 degree patient

Technician Set up Precise Scanning Location (Degrees) Posterior Chamber not Well

Delineated No distortion of Angle All 4 quadrants at a time

Contact Axial Resolution 50µm Sound Energy Supine

Scanning Location less precise(Quadrants)

Posterior Chamber Well Delineated

Distortion of Angle 1 Quadrant at a time

SCHEIMPFLUG PHOTOGRAPHY

THANK YOU