2. Introduction
Albrecht von Graefe in 1869
It is characterized by normal or increased IOP associated with axial
shallowing of the entire anterior chamber in the presence of a patent
peripheral iridotomy
After surgery in patients with primary angle closure and primary
angle-closure glaucoma
Synonyms:
1. Ciliary block glaucoma
2. Aqueous misdirection syndrome
3. Direct lens-block glaucoma
3. Prevalence
2% to 4% - h/o of acute or chronic angle-closure glaucoma that have
undergone filtration surgery
1.3 % - glaucoma surgery alone or combined with cataracts
2.3%- Penetrating surgery
Women are three times more likely than men
4. Predisposing Factors
Axial hyperopia
Nanophthalmos
Disorders of anatomical proportions in the anterior chamber
chronic angle closure with plateau iris configuration
History of malignant glaucoma in the fellow eye.
8. Shaffer and Hoskins
Posterior diversion of aqueous flow causes accumulation of aqueous
behind a posterior vitreous detachment with secondary forward
movement of the iris-lens diaphragm
Collections of fluid behind the vitreous gel, which also seemed more
dense than normal, and believed that this prevented forward flow of
aqueous
They postulated a valve-like mechanism by which aqueous humour
was “misdirected” posteriorly.
9. Epstein and colleagues
Anterior displacement of the vitreous due to posterior diversion of
aqueous
Associated thickening of the anterior hyaloid, and they were able to
demonstrate an impedance to flow across the intact anterior hyaloid
The accumulation of aqueous within the posterior segment forces the
ciliary body and the anterior hyaloid face forward, shallowing the
anterior chamber and causing secondary angle closure
10. Chandler et all
Laxity of lens zonules coupled with pressure from the vitreous leads to
forward lens movement
A vicious circle is set up in that the higher the pressure in the
posterior segment, the more firmly the lens is held forward
11. Quigley et al.
Proposed that the precipitating event which increases vitreous
pressure is choroidal expansion
Initial compensatory outflow of aqueous along the posteroanterior
pressure gradient causes shallowing of the anterior chamber.
Choroidal expansion has been detected on UBM in eyes with
malignant glaucoma, and choroidal effusion secondary to angio-oedema
has also been reported to result in malignant glaucoma
12. Predisposing Anatomical features
Incorrect anatomical relationships lead to disruptions in the direction
of aqueous humour flow
The place of increased resistance may be located at the level of the
iris-lens, ciliary-lens, iris-hyaloid, and ciliary-hyaloid block
Structures that are particularly related to the development of
malignant glaucoma and its clinical picture:
1. Sclera
2. Lens
3. Choroid
4. Vitreous body
13. Sclera– a thick sclera may lead to partial stenosis of the vortex veins,
impairing normal venous outflow and causing overfilling of the
choroid
Lens –Disproportions between its volume and the volume of the
entire eyeball
Choroid – the choroid has a lobular structure with a tendency for
accumulation of blood and thickening when outflow is impaired.
Secondary, ciliary body and iris rotate to the front in patients with
malignant glaucoma closing access to the filtration angle from the
back.
14. Vitreous body –optically clear areas within the vitreous body –
reservoirs of aqueous humour trapped in its gel structure
In aphakic eyes, the anterior surface of the vitreous body may directly
adhere to the ciliary processes
Highly resistant anterior hyaloid membrane may be observed in
aphakic and pseudophakic eyes
15. Clinical Features
Myopic shift - Anterior dislocation of the iris-lens diaphragm with secondary
improvement of near vision
Narrowing or shallowing of the circumferential and central part of the
anterior chamber even if patent iridotomy or iridectomy is present.
Persistent symptoms - Anterior adhesions due to the long-lasting shallowing
of the anterior chamber
Increased IOP
No decrease of IOP in response to conventional antiglaucoma treatment
16.
17. Examination
Medical history
1. Determination of predisposing factors
2. Symptoms
Slit lamp examination
1. ACD - axial (central and peripheral) shallowing of the anterior chamber
2. Patency of the iridotomy
3. Seidel test should be performed to exclude filtering bleb leaking after
filtration surgery.
4. Posterior segment : Ruling out choroidal detachment or suprachoroidal
hemorrhage
Tonometry – usually reveals increased IOP
18.
19.
20. DDx
Glaucoma with pupillary block
Closure of anterior chamber angle
Laser peripheral iridotomy is the treatment of choice
Unlike malignant glaucoma the anterior chamber usually remains
deeper in the center than on its circumference
21. Angle closure glaucoma
Shallowing of the anterior chamber occurs symmetrically
Sudden increase in IOP
Microcystic edema of the cornea
Conjunctival injection
22. Choroidal effusion
Cause:
1. inflammatory (trauma and intraocular surgery, scleritis, following
cryocoagulation and photocoagulation, chronic uveitis, Vogt-Koyanagi-
Harada disease)
2. Hydrostatic causes (hypotony and wound leak, dural arteriovenous
fistula, abnormally thick sclera in nanophthalmos)
IOP may be normal but is often reduced in uveal effusion secondary to
inflammatory factors.
23. Abnormal
amounts of
fluid in the
choroid
Thickening of
the choroid
accumulation
of fluid in the
suprachoroid
space
24. Suprachoroidal hemorrhage
Shallowing of the anterior chamber coexists with increased IOP, sudden pain,
and the presence of a haemorrhagic, non-serous detachment of the choroid in
biomicroscopic and ultrasonographic examination.
It occurs most often within 1 week after surgery, rarely later
may be also related to postoperative hypotony
25. Ultrabiomicroscopy (UBM)
The rotation of the ciliary body to the front and shallowing of the
anterior chamber
Marked displacement of the structures of the anterior segment
Peripheral irido-corneal touch
Forward shift of the lens may be noted
27. Medical
Cycloplegia
Mydriatics (atropine and phenylephrine) should be given immediately in
order to tighten the lens zonules and pull the anteriorly displaced
lens backwards
In some cases, Atropine is needed upto one year to avoid
recurrence.
MIOTICS – CONTRAINDICATED promoting zonular relaxation
and encourage forward lens movement.
Anti-Inflammatory Medication :
Topical steroids can help to reduce inflammation
28. Intraocular Pressure Reduction
Oral acetazolamide and topical beta-blockers and alpha agonists are used
to reduce aqueous production.
Reduction of Vitreous Volume.
Osmotic agents (mannitol or glycerol) are used to reduce vitreous
volume, deepen the anterior chamber, and possibly increase vitreous
permeability
29. Laser
AIM: to restore a normal aqueous flow pattern by establishing a direct
communication between the vitreous cavity and anterior chamber.
Disruption of Anterior Hyaloid Face
30. Laser of Ciliary Processes.
The successful use of transscleral cyclodiode laser photocoagulation in
pseudophakic patients can help eliminate an abnormal vitreociliary
relationship by posterior rotation of the ciliary processes secondary to
coagulative shrinkage
Often a single session of therapy is sufficient over 1-2 quadrants
Cyclocryotherapy has been used in the past but no longer has a place
in modern management
31. Surgical
The purpose of the vitrectomy is again to disrupt the anterior hyaloid
face and release fluid trapped within the vitreous
Anterior vitrectomy via pars
plana approach and/or in
combination with reformation
of the anterior chamber with
air +/- lens extraction
Iridectomy-hyaloido-zonulectomy
+ anterior
vitrectomy ( anteriorly via the
iridectomy or pars plana )
In phakic patients:
phacoemulsification-vitrectomy
(with zonulo-hyaloidectomy-
iridectomy)
In refractory cases:
Complete pars plana
vitrectomy along with lens
+removal of the entire hyaloid
face as well as creation of
vitrectomy tunnel
32.
33. Conclusion
Malignant glaucoma – Therapeutic challenge
Patients with h/o MG in fellow and PACG should be closely followed
in after glaucoma filtration surgeries
Good prognosis with current treatment modalities
The posterior surface of the iris, in the pupillary margin, comes in contact with the lens
The increased pupillary block obstructs the flow of the aqueous humour from the posterior chamber to the anterior chamber, resulting in increased pressure in the posterior chamber and forward bowing of the peripheral iris
Whatever the true mechanism, the fact that it is relieved when a direct communication is made between the anterior chamber and vitreous cavity supports the theory that the lens, anterior vitreous, and ciliary processes are intimately involved in the pathogenesis