angle closure glaucoma

ANGLE CLOSURE GLAUCOMA

-Anira Iqbal

Batch 2011

CLASSIFICATIONAngle-closure

GlaucomaPrimary Secondary

Acute (AACG)

Chronic (CACG)

TERMINOLOGIESPrimary Angle

Closure Disease :Narrow angle of AC

Apposition of peripheral iris against TM Obstruction of aqueous outflow

Primary Angle Closure Glaucoma :

+ Optic Disc(OD) Changes

+ Visual field defects(VFD)

RISK FACTORS

Demographic Anatomic

Age – 60 to 70 y/o

Gender – M:F 1:3

Heredity – Anatomic RF

Race – SE Asians, Chinese, Eskimos >> Blacks

HM– Short axial length,Shallow AC

Iris – lens diaphragmplaced anteriorly

Plateau Iris config.

Narrow angle of AC

Small eyeball Large lens

Smaller D of cornea

Bigger size of CBAnterior insertion of iris on

CB

PATHOGENESIS

Pupillary block mechanism (70%)

Phacomorphic mechanism (20%)

Plateau Iris configuration (10%)

PUPILLARY BLOCK MECHANISM

Precipitating factors :1. Physiological mydriasis – Reading in dim light,

watching tv in dark room, sympathetic overactivity in anxiety/emotional stress.

2. Pharmacological mydriasis• Mydriatics : Phenylephrine, Tropicamide,

Cyclopentolate, Homatropine, Atropine• Tranquilizers• Bronchodilators• Anti-depressants• Vasoconstrictors3 Pharmacological miosis – Echothiophate, Pilocarpine

Mechanism :Mydriasis mild dilatation of pupil Inc apposition

b/w iris and lens Relative Pupillary Block (RPB) Aq. Collects in PC pushes iris anteriorly Iris Bombe contact of iris with cornea Appositional angle closure Inc IOP formation of peripheral ant. Synechiae Synechial angle closure

Miosis contract ciliary muscles Zonules relax lens moves forward contact of iris with lens

PLATEAU IRIS• Also c/d Angle closure Glaucoma without

pupillary block.• Insertion of iris anteriorly on ciliary body or

displacement of ciliary body anteriorly apposition of peripheral iris with TM Plateau iris configuration iridotomy if still acute ACG occurs spontaneously/after pharmacological dilation Plateau iris syndrome Miotics + laser peripheral iridoplasty

CLASSIFICATIONClinical (Based on symptoms)• Latent primary ACG• Subacute/Intermittent PACG• Acute PACG• Chronic PACG

Association of International Glaucoma Societies (AIGS) – (Based on signs) :

• Primary angle closure suspects (PACS) – Latent PACG

• Primary angle closure (PAC) – Subacute + Acute

• Primary angle closure Glaucoma (PACG) - chronic

PACS• Symptoms – Absent• Presenting situations – Glaucoma Screening

Programme Routine ocular

exam Fellow eye in pt of

acute PAC• Signs:1. Eclipse sign

2. Slit lamp biomicroscopy – Dec axial AC depth - Convex shaped iris-

lens diaphragm - Close proximity of

iris to cornea in periphery3. Von- Herick Slit-lamp grading of angle

Diagnostic criteria• Gonioscopy – iridotrabecular contact without PAS• IOP – normal• OD – No glaucomatous change• VF – Normal

ANGLE IS AT RISK.

PACPresents in form of:1. Asymptomatic/Quiescent PAC PACG2. Subacute PAC3. Acute PAC

Diagnostic criteria :• Gonioscopy – Irido-trabecular contact• IOP elevated and/or PAS +• OD – normal• VF – normal

ANGLE IS ABNORMAL EITHER IN FUNCTION (IF INC IOP) OR IN STRUCTURE (IF PAS)

SUBACUTE PAC• PPt factors Attack of transient rise in IOP

(45-55 mm HG) – lasts for a few mins to 1-2 hours.

Symptoms• Episode – unilateral transient blurring of vision Coloured halos around light Headache, browache, eyeache on

affected side• Bright light/sleep physiological miosis self

termination of attack• Recurrent attacks – no symptoms b/w attacks

ACUTE PAC• Ppt factors pupillary block sudden closure of

angle attack of rise in IOP does not terminate on it ’s own sight threatening

Symptoms• Sudden severe pain• Nausea, vomiting• Rapidly progressive impairment of vision• Redness• Photophobia• Lacrimation

Signs• Lids – oedematous• Conjunctiva – chemosed,

congested• Cornea – oedematous,

insensitive• AC – shallow• Angle of AC – completely

closed on gonioscopy• Iris – discoloured• Pupil – semidilated,

vertically oval, fixed, non reactive to light/accomodation

• IOP – inc – b/w 40-70 mmHg

• OD – oedematous, hyperaemic

• Fellow eye – Shallow AC, occludable angle

PACG• PAC untreated gradual synechial closure of

angle of AC PACGDiagnostic criteria :• Inc IOP• PAS +• OD – glaucomatous cupping• VFD – similar to POAG• Gonioscopy – iridotrabecular contact

ANGLE IS ABNORMAL IN FUNCTION AND STRUCTURE