Management of Glaucoma Dr AR Rajalakshmi
Management of Glaucoma
Dr AR Rajalakshmi
• Aim of Glaucoma management• When and how to treat• Various treatment modalities
Glaucoma Management
AIM:• to prevent functional impairment of vision.
• Currently the only proven method of achieving this is the lowering of IOP.
MECHANISM
• Decreased aqueous production
• Increased facility of outflow (trabecular / uveoscleral)
• Intraocular osmotic fluid reduction
Treatment goals
Target pressure:• An IOP level is identified below which further damage
is considered unlikely
• To Assess: – the severity of existing damage (particularly a greater vertical
C/D ratio and a greater mean deviation on visual fields), – the level of IOP, CCT, – the rapidity with which damage occurred if known, and – the age and general health of the patient;
Classification
I. Prostaglandin analogues
II. Beta Blockers
III. Alpha-2-agonists
IV. Carbonic anhydrase inhibitors
V. Miotics
VI. Osmotic agents
Prostaglandin derivatives
Mode of Action:• preferred first-line treatment for glaucoma• enhancement of uveo-scleral aqueous outflow• Duration of action: several days• Administration once/day (at bedtime) • IOP by 25 –34 %
Agents Latanoprost 0.005%• fewer ocular adverse
events than other PG agents
• Often used first line
Travoprost 0.004%• Similar to latanoprost, • May lower IOP to a
slightly greater extent, particularly in black patients
Bimatoprost 0.03%• Shown to have a greater IOP-
lowering effect than the other PG agents
• More conjunctival hyperaemia & less iris hyperpigmentation
Tafluprost • Newer prostaglandin derivative,• Well tolerated and cause less
disruption of the ocular surface.
Side effectsOcular• Conjunctival hyperaemia • Eyelash lengthening, thickening,
hyperpigmentation • Irreversible iris
hyperpigmentation • Periorbital fat loss • deepening of the upper lid
sulcus• Hyperpigmentation of periocular
skin – Common but reversible
Systemic side effects • occasional headache, • precipitation of migraine in susceptible
individuals,• malaise, myalgia,• skin rash and • mild upper respiratory tract symptoms.
• C/I: Uveitic glaucoma, H/O herpes keratitis
Beta Blockers
• Act by decreasing aqueous production
• Eg: Timolol (0.5%), Betaxolol (Cardioselective),
Levobunolol, Carteolol, Metipranolol
• Most commonly used ocular hypotensive agent
especially in developing countries
• Given twice daily
• S/E: Ocular: Tachyphylaxis, allergy, punctate keratitis
Systemic: Bronchospasm (nonselective agents), bradycardia, nocturnal hypotension,worsening of heart failure and peripheral vascular disease, depression, impotence,dyslipidemia
• C/I: COPD, Heart failure, Diabetics(masking of hypoglycemia)
Timolol available forms- 0.25% and 0.5% solutions used twice daily• Gel-forming preparations of 0.1%,
0.25% and 0.5% are used once daily.
Betaxolol twice daily • lower hypotensive effect than
timolol. • optic nerve blood flow may be
increased due to a calcium-channel blocking effect, so that visual field preservation may be superior.
• Betaxolol is relatively cardioselective (beta-1 receptors), so causes less bronchoconstriction.
Levobunolol once or twice daily • similar profile to timolol.
Carteolol twice daily is similar to timolol • exhibits intrinsic
sympathomimetic activity. • more selective action on the eye
than on the cardiopulmonary system and lower systemic side effect incidence.
Metipranolol twice daily • similar to timolol • linked with granulomatous
anterior uveitis.
Alpha-2 agonists
• Decrease aqueous production by acting on the ciliary epithelium; also have some effect on uveo-scleral outflow
• Eg.Brimonidine (0.2%), Apraclonidine (1%)
• Apraclonidine is commonly used to treat transient IOP spikes following laser treatment of the anterior segement
• S/E: allergic conjunctivitis, uveitis, eyelid retraction, xerostsomia, fatigue
• C/I: in children less than 2 years as it crosses BB barrier and causes depression and hypotension, along with MOA inhibitors as they precipitate hypertensive crisis
Brimonidine 0.2% twice daily • Allergic conjunctivitis is
relatively common• Granulomatous anterior
uveitis - rare.
Apraclonidine 1% (or 0.5%) • used principally to prevent
or treat an acute rise in IOP following laser surgery on the anterior segment. The
• It is generally not suitable for long-term use
• because of a loss of therapeutic effect over weeks to months and a
• high incidence of local side
Carbonic Anhydrase Inhibitors• Inhibit aqueous secretion; supplementary neuroprotective
effect
• Acetazolamide (oral) 250-1000mg in divided doses. Also
available as sustained release tablets. Another oral drug is
Methazolamide
• Useful particularly in acute glaucoma for immediate short
term control of IOP• Topical forms include Dorzolamide 2%, Brinzolamide 1%
which are commonly used twice daily.
• S/E: Ocular: allergic
blepharoconjunctivitis, corneal decompensation (esp in patients with endothelial dysfunction), transient stinging sensation and bitter taste. Rarely choroidal effusion.
Systemic: Paresthesia, hypokalemia, GI symptoms, dose-related bone marrow suppression and aplastic anemia
• C/I: sulpha allergy (relative)
Miotics
• Cholinergic agonists used in treatment of angle closure glaucoma to terminate an acute attack.
• 2 main mechanisms: 1)Pull the peripheral iris away from the trabeculum
thereby opening the angle(useful in PACG). 2) Contraction of longitudinal muscle of ciliary body
hence increasing outflow (useful in POAG).
• Eg: Pilocarpine 1% qid was used previously for POAG, Carbachol
• S/E: Miosis, browache, myopic shift and exacerbation of symptoms of nuclear cataract.
• Systemic side effects include bradycardia, bronchospasm, GI symptoms, salivation
Osmotic agents• They reduce IOP by drawing water into the blood. • The effect is short term and is used in resistant
acute angle closure and prior to intraocular surgery to reduce high IOP.
• Mannitol intravenously 1gm/kg of a 20% solution over 30-60 minutes
• Glycerol orally 1g/kg of a 50% solution• Isosorbide is a safer alternative in diabetics than
glycerol
• S/E: CVS overload, headache, nausea, confusion
• C/I: in cardiac and renal patients for risk of volume overload, glycerol in uncontrolled diabetes
Combined preparations • Combined preparations with similar ocular hypotensive
effects to the sum of the individual components • improve convenience and patient compliance. • cost effective
• Cosopt®: timolol and dorzolamide, administered twice daily. • Xalacom®: timolol and latanoprost once daily. • TimPilo®: timolol and pilocarpine twice daily. • Combigan®: timolol and brimonidine twice daily. • DuoTrav®: timolol and travoprost once daily. • Ganfort®: timolol and bimatoprost once daily. • Azarga®: timolol and brinzolamide twice daily. • Simbrinza®: brimonidine and brinzolamide; a new combination – the only one that does not contain the beta-blocker timolol; administered twice daily.
Class/Compound Conc Dose Mech of action IOP Reduction
Ocular S/E Systemic S/E Comments
PG ANALOGUESLatanoprost
Travoprost
Unoprostone
Bimatoprost
Tafluprost
0.005%
0.004%
0.15%
0.03%
0.0015%
HS
HS
Bd
HS
HS
uveo scleral outflow
Both trabecular and uveoscleral outflow
25-32%
13-18%
Hyperpgt of iris/lashesHypertrichosisBlurred vision, Keratitis, CME, anterior uveitis, conjunctiva!hyperemia, exacerbation ofherpes keratitis
Flu like symptom, joint pain,headache
Peak-10-14 hrs
Washout:4-6 wks
Peak & wahout period unknown
Class/Compound Conc Dose Mech of action IOP Reduction
Ocular S/E Systemic S/E Comments
BETA BLOCKERSNon selectiveTimolol
Levobunolol
Metipronolol
CarteololHydrochloride
SelectiveBetoxolol
0.5%
0.5%
0.3%
1.0%
0.25%
Bd
Aqueous production 20-
30%
15-20%
Blurring, irritation, cornealanesthesia, punctate keratitis,allergy;
Bradycardia, heart block,bronchospasm,loweredblood pressure, decreasedlibido, CNS depression,mood swings, reducedexercise ToleranceIntrinsic sympathomimetic
Fewer pulmonary complications
Peak: 2-3 hoursWashout: 1 month
Peak: 2-6 hours
Peak: 2 hours
Peak: 4 hoursWashout: 1 month
Peak: 2-3 hoursWashout: 1 month
Class/Compound Conc Dose Mech of action IOP Reduction
Ocular S/E Systemic S/E Comments
Alpha-Adrenergic agonistsSelectiveApraclonidinehydrochloride
Brimonidinetartrate 0.2%
0.5%
0.2%
TDS
TDS
Decrease aqueous production,decreaseepiscleralvenous pressure
Decreases aqueousproduction,increasesuveoscleraloutflow
20-30%
20-30%
Irritation, ischemia, allergy,eyelid retraction, conjunctiva!blanching, follicularconjunctivitis, puritis,dermatitis, ocular ache,photopsia, miosisBlurring, foreign-bodysensation, eyelid edema,dryness, less ocularsensitivity/allergy than withapraclonidine
Hypotension, vasovagalattack, dry mouth and nose,Fatigue
Headache, fatigue,hypotension, insomnia,depression, syncope,dizziness, anxiety, drymouth
Peak: <1-2 hoursWashout: 7-14 days
Peak: 2 hoursWashout: 7-14 days
Class/Compound Conc Dose Mech of action IOP Reduction
Ocular S/E Systemic S/E Comments
Parasympathomimetic agents
Pilocarpine HCI 0.5,1 .0, 2.0, 3.0,4.0, 6.0%
2-4 times
Increasestrabecularoutflow
15-25%
Posterior synechiae, keratitis,miosis, brow ache, cataractgrowth, angle-closurepotential, myopia, Retinal tear/detachment dermatitis,change in retinal sensitivity,color vision changes,epiphora
Increased salivation,increased secretion(gastric), abdominal cramps
Peak: 1 1/2 -2 hoursWashout: 48 hours
Class/Compound Conc DosePerday
Mech of action
IOP Reduction
Ocular S/E Systemic S/E Comments
Carbonic anhydrase inhibitorsOralAcetazolamide
Acetazolamide(parenteral)
Methazolamide
250 mg
500 mg
500 mg5-10 mg/kg
25, 50, 100 mg
2-4 times
2 times
6-8 hrly
2-3 times
Decrease aqueous production
15-20% None
Acidosis,depression, malaise,hirsutism, flatulence,paresthesias, numbness,lethargy, blood dyscrasias,diarrhea, weight loss,renal stones, loss of libido,impotence, bone ma rrowdepression, hypokalemia,cramps, anorexia, alteredtaste, increased serumurate, enuresis
Caution insulfaallergy
Class/Compound Conc DosePerday
Mech of action
IOP Reduction
Ocular S/E Systemic S/E Comments
Carbonic anhydrase inhibitorsTopical
Dorzolamide
Brinzolamide
2%
1 %
2-3 times
2-3 times
Decrease aqueous production
15-20%
Induced myopia, blurredvision, stinging, keratitis,conjunctivitis, dermatitis
Same as above, except lessstinging when compared todorzolamide
Less likely
Bitter tastePeak: 2-3 hoursWashout: 48 hours
Class/Compound Conc DosePerday
Mech of action
IOP Reduction
Ocular S/E Systemic S/E Comments
Hyperosmotic agents
Mannitol (parenteral)
Glycerol (oral)
20%
50%
0.5-2.0 g/kgB Wt
2-3 times
1-1.5gm/Kg
Creates osmotic gradientDehydrates vitreous
15-20%
Rebound increase in IOP
Urinary retention, headachecongestive heart failureexpansion of blood volumediabetic complicationsnausea, vomiting, diarrheaelectrolyte disturbancerenal failure, mental confusion, backachemyocardial infarction
Caution in DM
C/I in heart failure,renal failure
Useful in acute rise in IOP
Can ppt DKA
Laser treatment of glaucoma • Laser Trabeculoplasty:Involves delivery of laser to the trabecular meshwork
with the aim of improving outflow.Done using the conventional Argon laser (ALT) or Nd-
Yag laser (Selective Laser Trabeculoplasty)
• Laser Iridotomy:Used principally in treatment of primary angle
closure and secondary angle closure with pupillary block.
An opening is created between 11 to 1 o clock on the outer third of the iris preferably over a crypt.
• Other uses of laser:
1. Diode laser cycloablation
2. Laser iridoplasty
Trabeculectomy
• It is a filtration surgery that lowers IOP by creating a
fistula between the anterior chamber and sub-Tenons
space.
• Indications: failure of medical therapy, avoidance of
medical polytherapy, primary therapy especially in
younger patients
• Technique
1. Limbal or fornix based flap of conjunctiva and Tenons capsule
fashioned superiorly
2. A trapdoor lamellar scleral flap incision usually triangular and
rectangular in shape
3. AC entered, peripheral iridectomy done and superficial scleral
flap and conjunctival flap are sutured and a bleb is created
Complications:• shallow anterior chamber,• failure of filtration,• Bleb leakage,• blebitis & endophthalmitis
Other surgeries
Non penetrating Surgeries• Deep sclerectomy
• Viscocanalostomy
• Canaloplasty
Drainage Shunts
• Classification of anti glaucoma medications• Mechanism of action, Side effects,
contraindications• Name the Laser procedures for glaucoma• Name the surgical procedure for glaucoma.