Basics in glaucoma
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Transcript Basics in glaucoma
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
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
Kinetic
Static
Visual fied defects
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
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
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
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:
Hyper mature
cataract
Corneal edema
AC reaction –
psuedo hypopyon
Open angles
Treatment
Anti glaucoma drugs
Topical antibiotic steroids
surgery
Phacomorphic Galucoma
Intumscent
cataractous lens
Shallow anterior
chamber
Treatment:
Antiglaucoma drugs
Laser iridotomy
surgery
Neo vascular Glaucoma
Retinal ischaemia
NVI
NVA
OPEN ANGLE
ANGLE CLOSURE
Causes
Ischeamic CRVO
Diabetes Mellitus
Miscellaneous
Carotid disease
Intra ocular tumor
Long standing RD
Symptoms & Signs
Decreased visual acuity
Congestion of Globe
Very high IOP and corneal edema
Severe pain
Aqueous flare
NVI
Gonioscopy - NVA
Treatment
Medical – topical Atropine & steroids
Retinal ablation / - DIODE CPC
Surgery:
Trab with MMC
Aqueous drainage shunts
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:
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:
Decreases aqueous
secretion
Increases uveo
scleral outflow
Side Effects:
Allergic
conjunctiviti s
Xerostomia
Drowsiness and
headache
PROSTAGLANDIN ANALOGUES
Mechanism
Decreases IOP by
increasing uveoscleral
outflow
Latanoprost F2 α
analogue.005%
Travoprost 0.004%
Bimatorpost 0.3%
Unoprostone 0.15%
BD
Side Effects
Conjunctival hypereamia
Eye lash growth and hyperpigmentation of
periorbital skin
Anterior uveitis
Cystoid macular edema
MIOTICS
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
Miosis
Browache
Myopic shift
Visual field defect
Carbonic Anhydrase Inhibitors
Inhibits aqueous
secretion
Topical CAI
Dorzolamide (Trusopt)
Brinzolamide (Azopt)
Systemic CAI
Acetazolamide
250mg BD
Side Effect
Parasthesia
Malaise
GI upset
Renal Stone
Blood dyscrasias
Hyper Osmotic Agents
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
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