Malignant glaucoma - Dr Shylesh B Dabke

Malignant Glaucoma

1. Malignant Glaucoma Dr Shylesh B Dabke Glaucoma Fellow Aravind Eye Hospital, Tirunelveli **Download and watch in Slideshow mode**

2. Introduction Not one disease but a group of disease with a common phenotype. Flat AC + High IOP after surgery for ACG “Malignant Glaucoma” – Often refractory to treatment “Aqueous Misdirection” – Fluid flows down the easiest route Von graefe – 1869

3. Most of the time aqueous flows forward into the trabecular meshwork however in aqueous misdirection aqueous is directed posteriorly

4. Many possible mechanisms in aqueous misdirection contact of ciliary body with lens and/or ant. hyaloid face blockage at the level of ciliary sulcus aqueous then flow the easiest way - Posteriorly ant. Hyaloid act as a one way valve trapping fluid in the posterior segment

5. A post-operative condition characterized by: Axial as well as peripheral shallowing of the anterior chamber. An accompanying rise of IOP due to secondary angle closure in the presence of In the presence of a patent iridectomy No response or even aggravation by miotics .

6. Other Names Ciliary block glaucoma Cilio -lenticular block glaucoma Aqueous misdirection syndrome Direct lens block angle closure Until a better understanding of the pathomechanism of the condition is attained,the term ‘malignant glaucoma’ expresses its seriousness and will continue to be used.

7. 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

8. Predisposing Factors Axial hyperopia Nanophthalmos C hronic angle closure with plateau iris configuration History of malignant glaucoma in the fellow eye

9. Theories Shaffer and Hoskins Quigley et al Epstein et al Chandler et al

10. Shaffer and Hoskins* – Posterior pooling of aqueous Posterior diversion of aqueous flow Accumulation of Aqueous behind a posterior vitreous detachment Secondary forward movement of the iris-lens diaphragm R. N. Shaffer and H. D. Hoskins, “The role of vitreous detachment in aphakic and malignant glaucoma,” Transactions of theAmerican Academy of Ophthalmology and Otolaryngology, vol. 58, pp. 217–228, 1954.

11. Cilio -lenticular( cilio-vitreal )block Tips of the ciliary processes rotate forward and press against the lens equator (in phakic eye) or against the anterior hyaloid (in aphakia ) Obsruction to the forward flow of aqueous G. E. Trope, C. J. Pavlin, A. Bau, C. R. Baumal, and F. S. Foster, “Malignant glaucoma: clinical and ultrasound biomicroscopic features,” Ophthalmology, vol. 101, no. 6, pp. 1030–1035, 1994 . C. Tello , T. Chi, G. Shepps , J. Liebmann , and R. Ritch , “Ultrasound biomicroscopy in pseudophakic malignant glaucoma,” Ophthalmology, vol. 100, no. 9, pp. 1330–1334, 1993 .

12. Anterior Hyaloid Obstruction - Epstein and colleagues May contribute to the cilio -lenticular block Breaks in the hyalid near the vitreous base . Possibly allow the posterior diversion of the aqueous One-way valve effect : fluid coming posteriorly closes the vitreous face against the ciliary body,preventing forward flow

13. Chandler & Grant* - Slackness of lens zonules 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 P. A. Chandler, “Malignant glaucoma,” American Journal of Ophthalmology, vol. 34, no. 7, pp. 993–1000,1951 This concept that the lens subsequently pushes the peripheral iris into the AC angle led to the proposed term “Direct lens block angle closure.”

14. Quigley et al* - Choroidal expansion The precipitating event which increases vitreous pressure is choroidal expansion The initial compensatory outflow of aqueous along the posteroanterior pressure gradient causes shallowing of the anterior chamber H. A. Quigley, D. S. Friedman, and N. G. Congdon , “Possible mechanisms of primary angle-closure and malignant glaucoma,” Journal of Glaucoma, vol. 12, no. 2, pp. 167–180, 2003. H. A. Quigley, “Angle-closure glaucoma—simpler answers to complex mechanisms: LXVI Edward Jackson Memorial Lecture,” American Journal of Ophthalmology, vol. 148, no. 5, pp. 657–669.e1, 2009 .

15. Final common pathway…….. Fluid build up behind the vitreous leads to vitreous condensation which exerts a forward force Establishment of a vicious cycle whereby the transvitreal pressure cannot be equalised by outflow of aqueous humour Anterior displacement of the lens-iris diaphragm An attack of malignant glaucoma

16. Clinical Forms Classical Malignant glaucoma . Malignant glaucoma in Aphakia . Malignant glaucoma in Pseudophakia . Miotic induced malignant glaucoma. Malignant glaucoma associated with bleb needling . Malignant glaucoma associated with infection and inflammation . Malignant glaucoma associated with other ocular disorders . Spontaneous Malignant glaucoma . ¹ SHIELDS Textbook of Glaucoma -- 6 th Edition

17. Classical Malignant Glaucoma Prototype and most common type. Typically occurs unilaterally following incisional surgical intervention for angle closure glaucoma. Occurs in 0.6 to 4 % of these cases. ¹ R. J. Simmons, “Malignant glaucoma,” British Journal of Ophthalmology, vol. 56, no. 3, pp. 263–272, 1972. P. A. Chandler, “Malignant glaucoma,” American Journal of Ophthalmology, vol. 34, no. 7, pp. 993–1000, 1951

18. Risk factors Partial or total angle closure at the time of surgery. A previous angle closure attack. Shallow AC ( axial hypermetropia ) and PAS. Overfiltration following glaucoma surgery. Previous MG attack in other eye. Classical Malignant Glaucoma Never related to the type of incisional surgery or immediate pre-op IOP.

19. Pseudophakic malignant glaucoma (A) aqueous pockets between the iris and anterior capsule; (B) pockets within the capsular bag and lens implant; (C) pockets between the posterior capsule and hyaloid face (D) aqueous trapped within the vitreous cavity behind an intact hyaloid face.

20. Phakic / Aphakic malignant glaucoma

21. Miotic induced malignant glaucoma May correspond to the institution of miotic therapy. Exact mechanism not known. May be through contraction of the ciliary body or associated forward shift of the lens with shallowing of the AC.

22. Malignant glaucoma associated with other ocular procedures/disorders Procedures Disorders Bleb needling Ocular infection – endophthalmitis caused by fungal keratomycosis and the atypical bacterium Nocardia asteroides . Trabeculectomy scleral flap suture lysis Corneal hydrops in keratoconus Diode laser cyclophotocoagulation Retinopathy of prematurity SPI Retinal detachment Pars plana vitrectomy Retinal vein occlusion Ocular trauma

23. Clinical Features Symptoms – Pain, redness and photophobia . Myopic shift Shallowing or flattening of the AC, with an accompanying rise of IOP, despite patent PI . Recent history of intraocular surgery,laser surgery or use of miotics . No choroidal detachment or suprachoroidal hemorrhage , or iris bombe . No decrease of IOP in response to conventional antiglaucoma treatment

24. Diagnosis of Malignant glaucoma Essentially clinical . Can be confirmed by F luoroscein T est . - I.V Fluorescein is injected into the antecubital vein. - In normal eyes,fluoroscein will not be seen to flow into the space behind the lens,IOL or vitreous space. - The diagnosis of MG is confirmed by noting the flow of fluoroscein tinged aqueous into the posterior segment.

25. Imaging - UBM Swelling or anterior rotation of the ciliary body. Forward rotation of the lens-iris diaphragm. Direct angle closure by physical pushing of the iris against the trabecular meshwork.

26. ASOCT

27. Differential diagnosis P upillary block glaucoma Suprachoroidal hemorrhage Choroidal effusion Acute primary angle closure glaucoma Phacomorphic glaucoma

28. Pupillary block glaucoma 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

29. Suprachoroidal hemorrhage Introperative or early post operative period IOP normal or elevated AC shallow- central and peripheral Fundus- bullous light brown choroidal elevations No relief by iridectomy

30. Choroidal effusion Introperative or early post operative period IOP low AC shallow- central and peripheral Fundus- bullous dark brown choroidal elevations No relief by iridectomy

31. Acute primary angle closure glaucoma Shallowing of the anterior chamber occurs symmetrically Sudden increase in IOP Microcystic edema of the cornea Conjunctival injection

32. Phacomorphic Glaucoma AC is more shallow in the affected eye. Associated with advanced cataract or a partially dislocated lens. No precipitating event such as the use of a miotic or surgery .

33. MANAGEMENT MEDICAL LASER PROCEDURES SURGICAL TREATMENT OF FELLOW EYE

34. Serious potentially sight threatening condition Admission The first step is to make an accurate diagnosis and exclude the differential diagnoses If the patency of the iridectomy is in doubt, a repeat laser iridotomy can be performed to exclude pupil block.

35. MEDICAL MANAGEMENT Initial medical therapy is directed at Simmons RJ, Thomas JV, Yaqub Malignant glaucoma. In: Ritch R, Shields MB , Krupin T, eds. The glaucomas . St Louis: CV Mosby, 1251–63 . - lowering IOP with aqueous suppressants - Attempting posterior displacement of the lens-iris diaphragm (and thus helping to break the ciliary block) with a strong cycloplegic such as atropine. - shrinking the vitreous with hyperosmotic agents The effect of medical therapy is often not immediate, but approximately 50 percent of cases will be relieved within five days.*

36. Recommended treatment regimen Cycloplegia : - Atropine(1%) eye drop TDS Paralysis sphincter muscle of ciliary body – leads to increased tension in zonules , flattens lens, moves lens posteriorly – deepens AC. In some cases, Atropine is needed upto one year to avoid recurrence. - Phenylephrine(2.5%) eye drops QID Tightens zonular complex by contraction of longitudinal muscle of ciliary body - Subconjunctival mydricaine MIOTICS – CONTRAINDICATED promoting zonular relaxation and encourage forward lens movement. Anti-Inflammatory Medication: - Topical steroids can help to reduce inflammation

37. For shrinkage of vitreous and/or reduction of aqueous production Beta blocker Alpha agonist- apraclonidine 1 % bd Oral acetazolamide 250 mg QID Oral Glycerol 50% 0.5-1 ml/kg IV mannitol 1 -2g/kg

38. Medical management - Principle Once the anterior chamber deepens and the intraocular pressure has been normalised, medical treatment can be gradually withdrawn. If high pressure continues after 5 days/ if lens-corneal touch occurs Peripheral anterior synechiae , posterior synechiae , cataract, and damage to the corneal endothelium surgical intervention should be considered

39. Laser treatment Argon laser photocoagulation of ciliary processes. Nd : YAG Laser assisted disruption of anterior hyaloid face or the posterior lens capsule and hyaloid face. Laser peripheral iridotomy .

40. Trans scleral cyclophotocoagulation If the ciliary processes are visible, argon laser photocoagulation can be used to shrink the ciliary processes . Not a highly useful technique because the visibility of ciliary processes is rare . L imited to patients whose glaucoma has been resistant to medical and surgical therapies , with no potential for improvement in visual acuity .

41. Nd : YAG laser assisted disruption of posterior capsule/anterior hyaloid face Mechanism involves puncturing the anterior hyaloid face and providing a new communication between sequestered aqueous and the anterior chamber. Through a large peripheral iridotomy or iridectomy , or through the pupil. The AC will start to deepen as soon as the anterior hyaloid face is disrupted

42. Nd:YAG laser carries a high risk of lenticular damage. A patent PI, good visualization & precise focusing are crucial. Phakic Eyes Pseudophakic or Aphakic eyes Nd:YAG laser capsulotomy with disruption of the anterior hyaloid face is often effective .

43. Surgical management Refractory to medical and laser therapy, surgical intervention to remove the vitreous is necessary to increase aqueous flow into the anterior chamber. The success of this was first described by Chandler.

44. Chandler's Malignant Glaucoma Procedure Posterior sclerostomy An 18-gauge needle 1 to 1.5 mL of fluid is aspirated. AC formed with Air bubble

45. - If signicant cataract – limited core Vitrectomy – Phacoemulsification with lens implantation- residual Vitrectomy – with hyaloido - zonulectomy -VPV) Pseudophakic Eyes Phakic Eye - Anterior pars plana vitrectomy + anterior hyaloidotomy – pars plana vitrectomy ± lensectomy Phakic Eye – Cataractous

46. Core vitrectomy surgery leads to resolution of malignant glaucoma This probably reflects the lack of effective removal of the anterior hyaloid in phakic eyes because of the risk of lens damage and subsequent cataract formation . P seudophakic eyes 65–90% P hakic eyes 25–50%

47. In the presence of a clear lens, treatment is rather more controversial Clear lens extraction should certainly be considered and discussed with the patient Pseudophakic eye Phakic eye- cataractous lens Phakic eye with clear lens Level of difficulty in surgical management

48. Management of fellow eye After an episode of malignant glaucoma in one eye, there is a high risk of this complication occurring in the fellow eye after a surgical intervention. The patient should be warned of this when consent is taken for surgery on the fellow eye . If the fellow eye has an occludable angle - perform a Laser PI .

49. Protection of the fellow eye from an attack Pre-op - Avoid miotic usage . Intra -op - Adminiser 4 % atropine and 2.5 % phenylephrine intraoperatively – pupil is dilated and ciliary body is paralyzed before surgery is completed. - Prevent AC shallowing intra-op – maintain a closed system or through the use of a viscoelastic material at the time of surgery . Post -op - Avoid hypotony and overfiltration .

50. Prevention of an attack in predisposed eyes Identify eyes at risk , preoperatively. In nanophthalmos , prophylactic sclerotomies may be required. Maintenance of anterior chamber depth both intra and post operatively. Aqueous overdrainage must be avoided in the early postoperative period by having a high scleral flap resistance – tight scleral flap sutures and judicious removal. Topical atropine at the end of the surgery and postoperatively. Discontinuation of cycloplegics should be undertaken with care in any patient considered at high-risk of MG .

51. Conclusion The precise mechanism of malignant glaucoma remains unclear but it is almost certainly closely related to the anatomical relation between lens, zonules , anterior vitreous face, and ciliary body. Reversal of aqueous misdirection is dependent on direct continuity between the vitreous cavity and anterior chamber which is difficult to achieve in the presence of a lens which is often relatively large . The management is controversial until the exact mechanism is more clearly understood . In the light of modern microsurgical techniques, reversal of ciliary block glaucoma can be achieved with preservation of good visual acuity and intraocular pressure control