malignant glaucoma

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Malignant Glaucoma

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Malignant Glaucoma

Dr.Dipak GulhaneDr.Rita Dhamankar

NORMAL ANTERIOR SEGMENT OCT

Malignant Glaucoma / Aqueous Misdirection Syndrome DefinitionVon Graefe 1869 A shallow or flat anterior chamber with an

inappropriately high intraocular pressure despite a patent iridectomy

European Glaucoma Society; II edition

Secondary angle closure glaucoma with ‘’posterior’’ pushing mechanism, without pupillary block, caused by the ciliary body and iris rotating forward

Malignant Glaucoma – AetiologySurgery for angle-closure glaucoma Spontaneously Cessation of topical cycloplegic therapyInitiation of topical miotic therapyLaser iridotomyLaser capsulotomyLaser cyclophotocoagulation

Malignant Glaucoma – Aetiology

Cataract extraction Seton implantationCentral retinal vein occlusion Argon laser suture lysis HyperopiaShort axial lengths, or nanophthalmos.[4]

Pathogenesis

Posterior misdirection of aqueous flow

Hyaloid membrane into or behind the vitreous body

Increase in vitreous volume

Shallower anterior chamber

Increase in intraocular pressure

Malignant glaucoma: cilio-lenticular block

Malignant glaucoma: cilio-vitrean block

Clinical Presentation High index of suspicion - necessaryA red, painful eye is surgery for acute angle-closure

glaucomaImmediately after surgery , may occur during surgery or

months to years laterCessation of cycloplegic therapy or the institution of

miotic drops

Clinical Presentation Slit-lamp

Shallow or flat anterior chamber both centrally and peripherally

No iris bombé to make the appropriate diagnosisIOP is elevated and the anterior chamber is axially shallow

Attempt to reform the anterior chamber postoperatively through the paracentesis site with viscoelastic substance,Great posterior resistance may be noted Anterior chamber may not deepen IOP may rise substantially.

Trigger factors Small, crowded anterior segmentAngle closure Swelling and inflammation of the ciliary processesAnterior rotation of the ciliary body Forward movement of the lens-iris diaphragm

DIFFERENTIAL DIAGNOSISCriterion Aqueous

MisdirectionPupillary Block Suprachoroidal

HemorrhageSerous Choroidal

Effusions

Intraocular pressure

Normal or elevated

Elevated Normal or elevated

Low

Anterior chamber depth

Shallow; flat centrally and peripherally

Shallow; flat peripherally, but deeper centrally

Shallow; flat centrally and peripherally

Shallow; flat centrally and peripherally

Relief by iridectomy

No Yes No No

Ophthalmoscopy Choroid and retina flat

Choroid and retina flat

Bullous light brown choroidal elevations

Bullous dark brown or dark red choroidal elevations

Ultrasound biomicroscopy

Anterior rotation of ciliary body and lens

Iris bombé with lens in normal position

- -

DIFFERENTIAL DIAGNOSISCriterion Aqueous Misdirection Pupillary

BlockSuprachoroidal

HemorrhageSerous Choroidal

Effusions

B-scan ultrasound

- - Smooth, thick, dome-shaped movement with little after-movement

Smooth, thick, dome-shaped membrane with little after- membrane

Heterogeneous echogenic space

Echolucent suprachoroidal space

Onset Intraoperative or early postoperative period.

Early postoperative period

Intraoperative or early postoperative period

Intraoperative or early postoperative period

Occasionally months to years later

Pupilary block v/s Malignant Glaucoma

Investigationes

Ultrasound A scan: axial length

Ultrasound B scan: exclude other pathologies

Ultrasound biomicroscoscopy

Ultrasound biomicroscopyConfirm the diagnosis by the visualitation of the

anterior segment structures: Irido-corneal touch Appositional angle closure Anterior rotation of the ciliary body Apposition to the iris

MANAGEMENT

Medical therapy

Laser therapy

Pars plana vitrectomy

Medical treatment

First step (good results in 50% of cases)Cycloplegia with atropin 1%x 4-6/dMydriasis with phenilephrin 2,5%x 4-6/dMechanism of action

posterior push of the irido-cristalinian diaphragm cilliary muscles relaxation

Long time treatment with atropin required recurences (sometime for several years)

β blockers, AIC , α agonists

Hyperosmotics agents: Glycerol (po), Manitol (2g/kg iv)

Miotics Are Contraindicated

Laser TherapyThe second line of treatmentNeodymium:yttrium-aluminum-garnet (Nd:YAG) laser -

aphakic and pseudophakic Large peripheral iridectomy Anterior hyaloid rupture to release the trapped aqueous

from the vitreous Several openings are made peripherally Placement of the iridectomies should be peripheral Peripheral placement will enable anterior migration of

the aqueous

Laser TherapyCorneal-lenticular contact

Risk of corneal decompensation Chamber should be reformed following Nd:YAG laser

hyaloidotomy Slit lamp Viscoelastic substance via a 30-gauge cannula Through the original paracentesis

Pars plana vitrectomy

MECHANISMTo debulk the vitreous To disrupt the anterior hyaloid face.

NEEDED Medical or or laser therapy failsPhakic eyes for which laser treatment is not a good option,

Pars plana vitrectomy

Pseudophakicvitrectomy + anterior hialoidotomy

Phakic Pars plana vitrectomy ± lensectomy

Lensectomy: - corneal oedema - dens cataract - no anterior chamber formation

during vitrectomy

Fellow eyeNarrow angle is present The laser peripheral iridectomy is performed before Risk of aqueous misdirection may be reduced after

iridectomy if the angle remains open and the IOP is normal

Failure to provide prompt therapy to the fellow - bilateral blindness.[2]

ConclusionThe prognosis depends of the severity and the anterior

situation

Malignant glaucoma remains a most difficult clinical problem in terms of diagnosis and management

The precise mechanism remains unclear and that why the management is controversial

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