Basics in glaucoma

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Basics in Glaucoma
Dr. Sharmila
Glaucoma clinic
Glaucoma

Glaucoma is an
optic neuropathy
with characteristic
appearance of the
optic disc and
specific pattern of
visual field defects
that is associated
frequently but not
invariably with
raised IOP
Classification of glaucoma
Open angle glaucoma
Angle-closure glaucoma
POAG
NTG
Juvenile open angle glaucoma
Glaaucoma suspect
Secondary open angle glaucoma
childhood
glaucoma
PACG with
pupillary block
Acute angle closure
Primary
congenital/infantile
glaucoma
subacute angle closure
CACG
Secondary angle closure
glaucoma with
pupillary block
Secondary angle closure
glaucoma without
pupillary block
Glaucoma associated
with congenital
anomalies
Secondary glaucoma
In children
Classification of glaucoma
OPEN ANGLE
GLAUCOMA
CLOSED ANGLE
GLAUCOMA
DEVELOPMENTAL
GLAUCOMA
SECONDARY
GLAUCOMA
POAG
Adult onset
 IOP > 21mm Hg
 Open Angles
 Glaucomatous nerve damage
 Visual field loss

Risk factors
Age > 65
 Black race
 Positive family history
 Myopia
 Thin Corneas

Pathogenesis
Increased resistance to aqueous
outflow
 Ischaemic Theory
 Mechanical theory

Pathogenesis
pathogenesis
Symptoms
Usually asymtomatic
 Rarely decreased visual
fields

Diagnosis of glaucoma



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
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History taking
Visual acuity and refractive state
Tonometry
Gonioscopy
Ophthalmoscopy
Perimetry
Tonometry



Indentation tonometry-schiotz
tonometer
Applanation tonometry
variable force-goldmann
Tonopen
variable area- maklakov
Non contact tonometer
Schiotz indentation Tonometry



Body –footplaterests on the cornea
Plunger
Weights5.5gm –
permanently fixed.
additional weights7.5g.10g,15g
Technique of schiotz tonometry








Anaesthetise cornea
Patient in supine position
Fixes on the target
Eyelids gently separated
Plunger rests on cornea.
Look for movement of the needle
Additional weights –if reading is <4
IOP derived from conversion table
Sources of error


Ocular rigidity
High ocular rigidity-high hyperopia,long
standing glaucoma,ARMD
Low ocular rigidity –high
myopia,osteogenesis imperfecta,miotic
therapy,retinal surgeries
Thick cornea-high value
Other
tonometers
TONOPEN
GOLDMAN APPLANATION
PERKINS
TONOMETER
Gonioscopy


Goniolens[direct]
Koeppe, layden,
barken
Gonioprism
Goldman single
mirror, two mirror,
three mirror
Zeiss four mirror
Posner four mirror
Normal angle structures
Ciliary body
band
 Scleral spur
 Trabecular
meshwork
 Schwalbe’s line

Ophthalmoscopy

Disc

Focal atropy
Concentric atrophy
Deepening of the cup
Advanced
glaucomatous cupping
Vascular changes
Haemorrhage,baring
of vessels, bayonetting
Retinal nerve fiber
layer changes
Peripapillary atrophy


Perimetry
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Kinetic
Static
Visual fied defects

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Paracentral
scotoma
Seidel scotoma
Arcuate scotoma
Double arcuate
scotoma
Nasal step
Angle Closure Glaucoma



With pupillary
block
Without pupillary
block
Diagnosis depends
on :


Anterior segment
examination
Gonioscopy
Risk factors
Age
 Gender
 Asians, Chinese, Eskimos
 Family history
 Hypermetropia

Pathogenesis
Increased opposition between iris and lens
enhance the degree of pupillary block
Increased pressure in posterior chamber
Increased peripheral iris bowing
Iris Bombe
High IOP
Types
Latent
 Subacute
 Acute congestive
 Post congestive
 Chronic
 Absolute

Acute Congestive Glaucoma

Symptoms
Severe pain and vomiting
 Unilateral visual loss
 coloured haloes
 Headache and vomiting

Signs


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Shallow AC
Corneal edema
Semi dilated pupil
High IOP
Closed angles
Treatment

Immediately
2% Pilocarpine
 Steroid eye drops
 Β blockers
 Analgesics and antiemetics
 Lie in supine position
 I.V. Mannitol + Oral T. Diamox

Treatment
MEDICAL
AFTER CORNEA CLEARS
LASER PI
IF NOT POSSIBLE
TRABECULECTOMY
Cont.d…

After 1 hr:
Pilocarpine 2%
 Yag PI


After 11/2 hr:
If IOP is still high
 50% oral glycerol
 20% Mannitol (1-2g/kg) I.V. over
45minutes

Laser Iridotomy
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

Clear corneas
Less than 1800 of
angle by PAS
Surgery:
Trabeculectomy
Congenital Glaucoma



1:10,000 births
65% are boys
Pathogenesis:
Maldevelopment
of the angle of anterior
chamber
Classification

Congenital Glaucoma

Infantile Glaucoma

Juvenile Glaucoma
Clinical Features


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Corneal edema
Buphthalmos
Breaks in DM
Optic disc cupping
Diagnosis



Increased IOP
Increased Corneal diameter > 11mm at 1yr
> 13mm
Treatment:
Goniotomy
 Trabeculotomy
 trabeculectomy

Lens related Glaucomas

Phacolytic:
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Hyper mature
cataract
Corneal edema
AC reaction –
psuedo hypopyon
Open angles
Treatment

Anti glaucoma drugs

Topical antibiotic steroids

surgery
Phacomorphic Galucoma
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

Intumscent
cataractous lens
Shallow anterior
chamber
Treatment:



Antiglaucoma drugs
Laser iridotomy
surgery
Neo vascular Glaucoma
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Retinal ischaemia

NVI
NVA



OPEN ANGLE
ANGLE CLOSURE
Causes
Ischeamic CRVO
 Diabetes Mellitus
 Miscellaneous

Carotid disease
 Intra ocular tumor
 Long standing RD

Symptoms & Signs
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Decreased visual acuity
Congestion of Globe
Very high IOP and corneal edema
Severe pain
Aqueous flare
NVI
Gonioscopy - NVA
Treatment


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Medical – topical Atropine & steroids
Retinal ablation / - DIODE CPC
Surgery:
Trab with MMC
 Aqueous drainage shunts
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
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Retrobulbar alcohol injection
Enucleation
Treatment Modalities in glaucoma
Medical
 Laser
 Surgery – Trabeculectomy
combined surgery

Anti Glaucoma Drugs

Β blockers


Decreases IOP by
decreasing aqueous
secretion
Contra indications:



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Congestive cardiac
failure
Heart block
Bradycardia
Bronchial asthma
Side effects


Iotim, Nyolol, Glucomol 0.5% bd
Ocular
Systemic
allergy
Bradycardia, Hypotention
SPK’s
Broncho spasm
tear secretion
Hallucination, head ache
nausea, dizziness
Alpha 2 Agonists

Brimonidine,
apraclonidine

Mechanism:

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
Decreases aqueous
secretion
Increases uveo
scleral outflow
Side Effects:
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

Allergic
conjunctiviti s
Xerostomia
Drowsiness and
headache
PROSTAGLANDIN ANALOGUES

Mechanism
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Decreases IOP by
increasing uveoscleral
outflow
Latanoprost F2 α
analogue.005%
Travoprost 0.004%
Bimatorpost 0.3%
Unoprostone 0.15%
BD
Side Effects

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Conjunctival hypereamia
Eye lash growth and hyperpigmentation of
periorbital skin
Anterior uveitis
Cystoid macular edema
MIOTICS
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Pilocarpine 1% 2% 3% 4% QID
Parasympathomimetic stimulates
muscarinic receptors in sphincter pupillae
& ciliary body
In POAG – increases aqueous outflow
In PACG – opens the angles
Side Effects

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
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Miosis
Browache
Myopic shift
Visual field defect
Carbonic Anhydrase Inhibitors

Inhibits aqueous
secretion

Topical CAI
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
Dorzolamide (Trusopt)
Brinzolamide (Azopt)

Systemic CAI
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Acetazolamide
250mg BD
Side Effect
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Parasthesia
Malaise
GI upset
Renal Stone
Blood dyscrasias
Hyper Osmotic Agents
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Glycerol 1g / kg in 50% solution
Mannitol 1-2g/kg in 20% solution
Side Effects:
 Cardiac or renal failure
 Urinary retention
 Head ache, nausea
Lasers in Glaucoma


Laser Iridotomy:
Indications:
 PACG
 Occludable angles
 SACG with pupillary block
 Combined mechanism glaucoma
Laser PI

prerequisites
 Instil 1% Apraclonidine
 Miotic pupil
 Laser settings 4-8 mJ
 Post laser steroid eye
drops
 Abraham lens
Complications

Bleeding
 Iritis
 Corneal burn
 Glare
 Diplopia
Surgery

Trabeculectomy:



A conventional filtering
procedure creates a new
channel for aqueous outflow
between the anterior chamber
and subtenons space without
the use of an artificial device
Partial thickness
Full thickness
Management of coexistent cataract
and glaucoma
Complications
Wound leak
 Excessive filteration
 Pupillary block
 Malignant glaucoma
 Hypotony
 Choroidal detachment

Failing bleb
SIGNS
•
Injection
•
Vascularisation
•
Thickening
•
Localization
•
High domed Bleb
•
Normal / High IOP
•
Low IOP
Initial few weeks
critical
Failing filtration
Frame work for Classification
• IOP
• Bleb
Failing filter – High IOP
Low localized Bleb
External
Internal
-
Subconjunctival fibrosis
-
Tight scleral flap sutures
-
Sclerectomy obstruction
Failing filter – High IOP
High domed bleb – encapsulated bleb or Tenon’s cyst
Failing filter - Low IOP
Low bleb
- Bleb leak
Elevated diffuse bleb - Over
Filtration
hypotony
Bleb Failure
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Argon laser suturolysis
0.2sec 50µ 500-700mw
Digital massage
Topical steroids
5FU injection
DF Nd yag laser
Needling of tenons cyst
REFRACTORY GLAUCOMA

AQUEOUS
DRAINAGE
IMPLANTS
Refractory glaucomas

Cyclo destructive procedures
New diagnostic and surgical
procedures

Central corneal thickness assessment
OPTICAL COHERENCE
TOMOGRAPHY
ULTRASOUND BIOMICROSCOPY
Classification of glaucoma
OPEN ANGLE
GLAUCOMA
CLOSED ANGLE
GLAUCOMA
DEVELOPMENTAL
GLAUCOMA
SECONDARY
GLAUCOMA
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