Malignant glaucoma
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Transcript of Malignant glaucoma
1869 Von Graefe1869 Von Graefe
Malignanat glaucoma =Malignanat glaucoma =shallowing of the central (axial) shallowing of the central (axial) anterior chamber in association with increased intraocular anterior chamber in association with increased intraocular pressure (IOP) and normal posterior segment anatomypressure (IOP) and normal posterior segment anatomy
Classical malignant glaucoma is reported to occur in 0.4–Classical malignant glaucoma is reported to occur in 0.4–6% cases of incisional surgery for primary angle-closure 6% cases of incisional surgery for primary angle-closure glaucomaglaucoma
Classification Classic malignant glaucomaClassic malignant glaucoma
: : ①①rare Cx of incisional surgery for primary angle closure glaucomarare Cx of incisional surgery for primary angle closure glaucoma
②②partial or total closure of the drainage at the time & axial partial or total closure of the drainage at the time & axial
hypermetropia is associated with increased risk hypermetropia is associated with increased risk
Nonphakic malignant glaucomaNonphakic malignant glaucoma
: : can occur in eye with or without glaucomacan occur in eye with or without glaucoma
Other malignant glaucoma syndromesOther malignant glaucoma syndromes
: : laser Tx, use of miotics , trabeculectomy bleb needlinglaser Tx, use of miotics , trabeculectomy bleb needling
Symptom
The first symptom is often an improvement in near vision The first symptom is often an improvement in near vision secondary to a myopic shift in refraction as the lens iris secondary to a myopic shift in refraction as the lens iris diaphragm moves forward.diaphragm moves forward.
In most eyes the IOP >21mmHg, In most eyes the IOP >21mmHg,
In some eyes the IOPIn some eyes the IOP≤ ≤ 21mmHg21mmHg
Pain ,inflammation ,corneal oedema Pain ,inflammation ,corneal oedema
mechanism(1)
Multifactorial conditionMultifactorial condition
:Occur in anatomically predisposed eyes:Occur in anatomically predisposed eyes
Alteration in the anatomic relationship of the lens, ciliaryAlteration in the anatomic relationship of the lens, ciliary
body,anterior hyaloid face,and vitreous→ forward body,anterior hyaloid face,and vitreous→ forward movement of the iris-lens diaphragmmovement of the iris-lens diaphragm
Exact mechanism remains unclearExact mechanism remains unclear
mechanism(2-1)
(1) Shaffer & Hoskins (1) Shaffer & Hoskins
①①PPosterior diversion of aqueous flow → accumulation of osterior diversion of aqueous flow → accumulation of
aqueous behind a posterior vitreous detachment aqueous behind a posterior vitreous detachment →forward movement of the iris-lens diaphragm→forward movement of the iris-lens diaphragm
②②valve-like mechanism by which aqueous humour valve-like mechanism by which aqueous humour
was“misdirected”posteriorly.was“misdirected”posteriorly.
③ ③Cause the posterior diversion of aqueous andCause the posterior diversion of aqueous and
the nature of the unidirectional valve remain unclear.the nature of the unidirectional valve remain unclear.
mechanism(2-2)
The mechanisms leading to the posterior diversion of The mechanisms leading to the posterior diversion of aqueousaqueous
(1) Ciliolenticular (Ciliovitreal) Block(1) Ciliolenticular (Ciliovitreal) Block
mechanism(2-3)
(2) Anterior Hyaloid Obstruction(2) Anterior Hyaloid Obstruction
The anterior hyaloid →Ciliolenticular blockThe anterior hyaloid →Ciliolenticular block Breaks in the hyaloid near the vitreous base → Posterior Breaks in the hyaloid near the vitreous base → Posterior
diversion of aqueousdiversion of aqueous
mechanism(3)
(2) Chandler(2) Chandler
①①Laxity of lens zonules coupled with pressure from Laxity of lens zonules coupled with pressure from the vitreous leads to forward lens movement.the vitreous leads to forward lens movement.
②②the higher the pressure in the posterior segmentthe higher the pressure in the posterior segment
→ → the more firmly the lens is held forwardthe more firmly the lens is held forward
mechanism(4)
(3) Quigley(3) Quigley
① ① PPrecipitating event which increases vitreous pressure is recipitating event which increases vitreous pressure is
choroidal expansionchoroidal expansion
② ② TThe initial compensatory outflow of aqueous along the he initial compensatory outflow of aqueous along the
posteroanterior pressure gradientposteroanterior pressure gradient → → shallowing of the shallowing of the
anterior chamberanterior chamber
mechanism(5)
(4) Final Common pathway(4) Final Common pathway
The transvitreal pressure cannot be equalised by outflow The transvitreal pressure cannot be equalised by outflow
of aqueous humour.of aqueous humour.
The anterior vitreous gel becomes less permeable to the The anterior vitreous gel becomes less permeable to the forward movement of gel.forward movement of gel.
Fluid buildup behind the vitreous → vitreous condensation Fluid buildup behind the vitreous → vitreous condensation
→ → exerts a forward force→ anterior displacement of the exerts a forward force→ anterior displacement of the
lens-iris diaphragmlens-iris diaphragm
Treatment(1) Medical Therapy(1) Cycloplegia: tighten the lens zonules & pull the anteriorly tighten the lens zonules & pull the anteriorly
displaced lens backwardsdisplaced lens backwards Use Use for for long periods of time periods of time
★ ★ TThe use of miotics are contraindicatedhe use of miotics are contraindicated
(2) Intraocular Pressure Reduction: Oral acetazolamideOral acetazolamide
topical beta-blockers & alpha agoniststopical beta-blockers & alpha agonists
(3) Reduction of Vitreous Volume: Osmotic agentsOsmotic agents
(4) Anti-Inflammatory Medication: Topical steroids (reduce Topical steroids (reduce inflammation )inflammation )
Treatment(2) Laser Therapy
(1) Restore a normal aqueous flow pattern by establishing a (1) Restore a normal aqueous flow pattern by establishing a
direct communication between the vitreous cavity and direct communication between the vitreous cavity and
anterior chamberanterior chamber
(2) Disruption of Anterior Hyaloid Face: Intact hyaloid face -pathogenic factor in malignant glaucomaIntact hyaloid face -pathogenic factor in malignant glaucoma Nd:YAG laser capsulotomy with disruption of the anterior Nd:YAG laser capsulotomy with disruption of the anterior
hyaloid face is often effectivehyaloid face is often effective
Treatment(3) (3) Laser of Ciliary Processes
Transscleral cyclodiode laser photocoagulation in Transscleral cyclodiode laser photocoagulation in pseudophakic patients → posterior rotation of the ciliary pseudophakic patients → posterior rotation of the ciliary processes secondary to coagulative shrinkage → eliminate processes secondary to coagulative shrinkage → eliminate an abnormal vitreociliary relationshipan abnormal vitreociliary relationship
An alternative option : direct argon laser treatment of theAn alternative option : direct argon laser treatment of the
ciliary processes through a peripheral iridotomyciliary processes through a peripheral iridotomy
Treatment(4) Surgical Therapy(1) Increase aqueous flow into the anterior chamberIncrease aqueous flow into the anterior chamber
: vitreous aspiration through an 18-guage needle via an incision vitreous aspiration through an 18-guage needle via an incision
through the pars plana by Chandler→ pars plana vitrectomythrough the pars plana by Chandler→ pars plana vitrectomy
(2) Core vitrectomy surgery Core vitrectomy surgery
:resolution of malignant glaucoma in 25–50% of the phakic :resolution of malignant glaucoma in 25–50% of the phakic
eyes vs 65–90% in pseudophakic eyeseyes vs 65–90% in pseudophakic eyes
(3)Cataract extraction+ vitrectomy in phakic eyes →increase from 25% ataract extraction+ vitrectomy in phakic eyes →increase from 25% to 83% if the posterior capsule is removedto 83% if the posterior capsule is removed
Treatment(5) ★★Definitive management Definitive management
: Phacoemulsification+: Phacoemulsification+Intraocular lens implantation +Intraocular lens implantation +Removal Removal
of the posterior capsule at time of vitrectomyof the posterior capsule at time of vitrectomy
A staged surgical approach: A staged surgical approach:
Debulk the vitreous, soften the eye, and deepen the anterior Debulk the vitreous, soften the eye, and deepen the anterior chamber by core vitrectomy→ Phacoemulsification chamber by core vitrectomy→ Phacoemulsification +intraocular lens implantation → Residual vitrectomy & +intraocular lens implantation → Residual vitrectomy & hyaloidectomy with removal of the retrolental posterior hyaloidectomy with removal of the retrolental posterior capsule capsule
Treatment(6) Management of the Fellow EyeManagement of the Fellow Eye
(1) High risk of this complication occurring in the igh risk of this complication occurring in the
fellow eye after a surgical interventionfellow eye after a surgical intervention
(2) Prophylactic measures Prophylactic measures Cessation of miotic dropsCessation of miotic drops Prolonged use of atropine after trabeculectomy Prolonged use of atropine after trabeculectomy Avoidance of anterior chamber shallowing in the Avoidance of anterior chamber shallowing in the
postoperative period (using anterior chamber postoperative period (using anterior chamber
viscoelastic and tight scleral flap suturing) viscoelastic and tight scleral flap suturing)