GLAUCOMA

EPIDEMIOLOGY

In the world, glaucoma is the third

leading cause of blindness-

an estimated 13.5 million people

may have glaucoma and

5.2 million of those may be blind.

GLAUCOMA DEFINITION

Progressive optic neuropathy leading to

irreversible damage of optic nerve fibres,

thus to excavation of the optic disc and to

specific visual field impairment.

ANATOMY

SUMMARY OF STEPS IN EYE EXAM

Visual Acuity

Pupillary examination

Visual fields by confrontation

Extraocular movements

Inspection of

– lid and surrounding tissue

– conjunctiva and sclera

– cornea and iris

Anterior chamber depth

Lens clarity

Tonometry

Fundus examination

– Disc

– Macula

– Vessels

GLAUCOMA

Physiology of aqueous circulation

Normal intraocular pressure = 10-22 mmHg

Balance of secretion and outflow

Higher IOP = decrease in ocular perfusion =

nerve damage

Visual acuity, visual field impairment

PRODUCTION AND OUTFLOW OF

AQUEOUS HUMOR

85%:

trabecular

meshwork

15%:

uveoscleral

EXAMINATIONS IN GLAUCOMA

Slitlamp biomicroscopy (chamber depth, cells in

AC, iris atrophy, pupil shape, lens: glaucom flecken)

IOP control: 1: digital 2: impression (Schiötz)

3: applanation (Goldmann) 4. air push 5. ORA

6. CorVis etc.

Visual field testing (central 30° glaucoma program

perimetry)

Gonioscopy: angle anatomy

Fundus, optic nerve head screening (cup/disc ratio)

INTRAOCULAR PRESSURE

MEASUREMENT Range: 10 – 22 mmHg

ANTERIOR CHAMBER

DEPTH ASSESSMENT

Likely shallow if

– ≥ 2/3 of nasal iris in shadow

GONIOSCOPY

EVALUATION OF ANGLE ANATOMY ON

GONIOSCOPIC EXAMINATION:

SCHAEFFER GRADE I-IV

NORMAL OPTIC NERVE HEAD „I.S.N.T” rule

Inferior > Superior > Nasal > Temporal

Neuroretinal rim

Excavation Elschnig ring

Superotemporal

Temporal Nasal

Inferotemporal

NORMAL DISC CUPPED DISC

C/D

C/D RATIO

DIAGNOSTIC TOOLS

Mechanism Parameters

CSLO (HRT)

Surface topograph

Rim area

ONH shape

SLP (GDx)

RNFL thickness

RNFL thickness deviation map

Nerve fibre indicator (machine learning

classifier)

OCT

RNFL thickness

Rim area

Macular thickness

CSLO: confocal scanning laser ophthalmoscopy; HRT: Heidelberg Retinal Tomograph;

ONH: optic nerve head;

SLP: scanning laser polarimetry; RNFL: retinal nerve fiber layer

OCT: optical coherence tomography

IMAGING TECHNIQUES I.

Confocalis scanning laser

ophthalmoscope (CSLO)

– Heidelberg Retina Tomograph (HRT)

Scanning laser polarimetry (SLP)

– GDx VCC

Optical coherence tomograph (OCT)

CONFOCAL SCANNING

LASER OPHTHALMOSCOPE Heidelberg Retina Tomography* (HRT II / HRT3)

*Heidelberg Engineering GmbH, Germany. http://opt.pacificu.edu/ce/catalog/9451-GL/HRT-Kirstein.html. Accessed 10 September 2007.

TOPOGRAPHY CROSS-SECTION OF PAPILLA

STEREOMETRIC PARAMETERS

T N

EXCAVATION

REFERENCE

LEVEL

50 m

RIM

Stereometric results ONH 0°–360°

Disc area 1.978 mm2

Cup area 0.946 mm2

Cup/disc area ratio 0.478

Rim area 1.032 mm2

Height variation contour 0.193 mm

Cup volume 0.182 cmm

Rim volume 0.135 cmm

Mean cup depth 0.224 mm

Maximum cup depth 0.504 mm

Cup shape measure - 0.074

Mean RNFL thickness 0.117 mm

RNFL cross section area 0.586 mm2

POAG

IMAGING TECHNIQUES II.

Confocal scanning laser ophthalmoscope

(CSLO)

– Heidelberg Retina Tomograph (HRT)

Scanning laser polarimetry (SLP)

– GDx VCC

Optical coherence tomograph (OCT)

SCANNING LASER

POLARIMETRY (SLP)

GDx VCC (Carl Zeiss Meditec, Inc.)

Carl Zeiss. Structure and Function: An Integrated Approach for the Detection and Follow-up of Glaucoma. Module 3a--GDx.

http://www.zeiss.de/C125679E00525939/EmbedTitelIntern/GDxTechnologyDescription/$File/GDx_Technology_Description.pdf.

GDX VCC EXAMINATION CHART

TSNIT parameters

OD actual

value

OS actual

value

TSNIT average 39.99 43.10

Superior average 36.76 46.02

Inferior average 53.22 55.29

TSNIT std. dev 19.09 22.63

Inter-eye symmetry 0.93

Nerve fibre indicator 66 49

P>5% P<5% P<2% P<1% P<.5%

Thickness

Deviation map

TSNIT curve

Normal Glaucoma

Parameters

IMAGING TECHNIQUES III.

Confocalis scanning laser

ophthalmoscope (CSLO)

– Heidelberg Retina Tomograph (HRT)

Scanning laser polarimetry (SLP)

– GDx VCC

Optical coherence tomograph (OCT)

OPTICAL COHERENCE TOMOGRAPH

(OCT)

Time domain (Stratus-Zeiss)

Fourier domain (OPTOVUE)

OPTICAL COHERENCE TOMOGRAPHY

(OCT) – PERIPAPILLARY RETINAL

NERVE FIBER LAYER ANALYSIS

OCT „RNFL thickness”

OD (N=3) OS (N=0) OD-OS

Imax/Smax 0.69 0.00 0.69

Smax/Imax 1.46 0.00 1.46

Smax/Tavg 2.63 0.00 2.63

Imax/Tavg 1.81 0.00 1.81

Smax/Navg 2.15 0.00 2.15

Max-Min 95.00 0.00 95.00

Smax 128.00 0.00 128.00

Imax 88.00 0.00 88.00

Savg 96.00 0.00 96.00

Iavg 57.00 0.00 57.00

Avg. Thick 65.26 0.00 65.26

Carl Zeiss Meditec. http://www.zeiss.de/88256DE3007B916B/0/C26634D0CFF04511882571B1005DECFD/

$file/stratusoct_en.pdf.

POAG

PERIMETRY

Very important in the diagnosis and

management of glaucoma

Method: Static – kinetic

Goldmann – automated (suggested)

Humphrey automated perimeter

(Carl Zeiss Meditec) Octopus 900 automated perimeter

(Haag-Streit AG)

European Glaucoma Society. Terminology and Guidelines for Glaucoma. 3rd Edition.

PERIMETRIC ANALYSES

Numeric maps:

Total deviation

Variable maps:

Total deviation

Grey scale

Pattern deviation

Pattern deviation

Numeric threshold map

VISUAL FIELD TESTING: CENTRAL 30°

GLAUCOMA PROGRAMME STATIC PERIMETRY

CLASSIFICATION OF GLAUCOMA Primary: etiology is unclear

1. Primary congenital glaucoma (goniodysgenesis, aniridia, megalocornea)

2. Primary open angle glaucoma=POAG (no pain, very slow visual impairment)

3. Primary angle closure glaucoma: PCAG

a.: acut attack (pain, redness, fast visual loss)

b.: chronic (less pain, not so fast visual loss)

4. Normal tension glaucoma

5. Ocular hypertension

Secondary: neovascular, traumatic, pseudoexfoliative, lens-related, etc.

PRIMARY CONGENITAL GLAUCOMA

Incidence: 1:10.000 live births

Etiology: trabeculodysgenesis, i.e. maldevelopment of the angle: flat/concave iris insertion

1. True primary congenital glaucoma: intrauterin IOP

2. Infantile glaucoma (onset before the 3rd birthday)

3. Juvenile glaucoma: 3-35 years

True PCG and

infantile glaucoma:

Buphthalmos

(large and cloudy

cornea, Haab-stria,

elevated IOP)

PRIMARY OPEN ANGLE

GLAUCOMA - Above 35 years

- Open angle on gonioscopic examination

- Glaucomatous damage of the optic nerve and/or visual

field

- Elevated IOP

Th.: IOP lowering eye drops, eye drop combinations,

laser treatment, filtration surgery

Follow up: IOP measurement every 3 months, visual

field testing every 6 months

PRIMARY ANGLE CLOSURE

GLAUCOMA

- Acute ACG

- Intermittent ACG

- Chronic ACG (creeping mehanism after acute ACG, periferal anterior synechiae)

plateau iris configuration: anterior iris insertion

plateau iris syndrome: anterior iris insertion + IOP

ACUTE AC GLAUCOMA

ABSOLUTE GLAUCOMA

Painful

Blind

Treatment

Laser/Cryotherapy

Absolute alcohol

Enucleation

RISK FACTORS

Old age Myopia

African-American race Blood Hypertension

Family History Diabetes Mellitus

High IOP Smoking

THERAPY OF GLAUCOMA

Pharmacological treatment

Laser treatment

Surgical treatment

PHARMACOLOGICAL

TREATMENT

BETA BLOCKERS (betaxolol, timolol, carteolol, levobunalol)

CARBONIC ANHYDRAZE INHIBITORS (acetazolamide*, dorzolamide, brinzolamide, methazolamide)

SYMPATHOMIMETICS (apraclonidine, brimonidine, epinephrine, dipivefrin)

CHOLINERGICS (pilocarpine, carbachol)

PROSTAGLANDIN DERIVATIVES = PGF2α analogues (latanoprost, travoprost, bimatoprost)

LASER TREATMENT

Trabeculoplasty (ALT, SLT)

Laser Peripheral Iridotomy (LPI)

Cyclophotocoagulation/cyclodestruction

SURGICAL TREATMENT

Goniotomy

congenital

Trabeculotomy

for congenital glaucoma's

Trabeculectomy

for adult glaucoma's

Implants

for difficult non responsive

THANK YOU FOR YOUR KIND

ATTENTION!

and your openness to

challenge the

“silent thief of sight”!