Surgical Management of Glaucoma-Elias.pptx

update on glaucoma management.

1. Surgical Management of Glaucoma Elias T( Ophthalmologist,MD )

2. outlines Introduction Overview of types of glaucoma surgery Trabeculectomy Aqueous drainage device Angle Surgery Non penetrating Surgery MIGS Combined Cataract and Glaucoma Surgery 2/4/2024 Glaucoma Surgeries - EliasT 2

3. Introduction Glaucoma refers to a group of progressive optic neuropathies characterized by an Excavated appearance of the optic disc, often described as cupped Loss of retinal ganglion cells and their axons and corresponding vision loss Eventual development of distinctive patterns of visual dysfunction (VF) Causes of glaucoma are multifactorial and include genetic and environmental IOP is a continuous risk factor for the development of glaucoma over its entire range By 2020 - 80 million people worldwide will have glaucoma 11.2 million bilaterally blind as a result 2/4/2024 Glaucoma Surgeries - EliasT 3

4. …cont. Factors that determine the IOP The rate of aqueous humor production The rate of drainage The level of episcleral venous pressure 2/4/2024 Glaucoma Surgeries - EliasT 4

5. Anatomical principle of glaucoma surgery 2/4/2024 Glaucoma Surgeries - EliasT 5

6. Glaucoma Surgery Usually undertaken when medical therapy is Not appropriate Not tolerated Not effective Not properly utilized by particular patient If medical therapy is failed (uncontrolled IOP or documented progression) As primary approach for both congenital glaucoma and pupillary block glaucoma 2/4/2024 Glaucoma Surgeries - EliasT 6

7. How to reduce IOP Enhance Outflow Physiological pathways: Trabecular meshwork- trabectome Schlemm’s canal – istent , ipass , icath Suprachoroidal space - Gold shunt Subconjunctival drainage: Trabeculectomy Non-penetrating surgery Aqueous drainage device Reduce inflow: Endoscopic cyclophotocoagulation 2/4/2024 Glaucoma Surgeries - EliasT 7

8. …cont. 2/4/2024 Glaucoma Surgeries - EliasT 8

9. …cont. Patient Selection History Physical Examination Laboratory Investigation 2/4/2024 Glaucoma Surgeries - EliasT 9

10. Chart flow 2/4/2024 Glaucoma Surgeries - EliasT 10

11. Trabeculectomy Is an incisional procedure Fistula is created between the anterior chamber and the subconjunctival space By passing the normal aqueous outflow pathway Protected by a superficial scleral flap 2/4/2024 Glaucoma Surgeries - EliasT 11

12. Indications Considered when surgical risks are outweighed by the potential benefits Failure of conservative therapy Optic nerve function is failing or is likely to fail Progressive VFL Progressive deterioration despite seemingly adequate IOP control Primary therapy Significant barriers to using medications regularly Patient preference 2/4/2024 Glaucoma Surgeries - EliasT 12

13. Contraindications Blind eye Conjunctival scar, thin sclera Active anterior segment neovascularization (rubeosis iridis) Active iritis 2/4/2024 Glaucoma Surgeries - EliasT 13

14. Preoperative Evaluation Patient’s general health Control inflammation, IOP & ocular surface infection Review medication Informing patient on purpose of and expectations about the procedure 2/4/2024 Glaucoma Surgeries - EliasT 14

15. …cont. Pre operatively, pt should understand Surgery alone rarely improves vision Surgery may fail completely Could lose vision as a result of surgery Glaucoma may progress despite successful surgery 2/4/2024 Glaucoma Surgeries - EliasT 15

16. Basic techniques of filtering surgery Exposure Traction suture for good surgical exposure Superior rectus traction suture- uses 4-0 silk Clear corneal traction suture- uses 7-0 polyglactin or silk 3/4th corneal thickness, 1mm from limbus, width of 4-5mm Better over SR traction suture 2/4/2024 Glaucoma Surgeries - EliasT 16

17. ...cont. 2/4/2024 Glaucoma Surgeries - EliasT 17

18. Conjunctival incision Is a critical step in all filtering procedures Most common cause of failure is scarring of filtering bleb 12-o’oclock/ one of superior quadrant position is preferred. Need to minimize tissue damage & bleeding. Limbus based vs fornix based. Recently fornix based flap favored, have similar success rates 2/4/2024 Glaucoma Surgeries - EliasT 18

19. FBCF Vs LBCF 2/4/2024 Glaucoma Surgeries - EliasT 19

20. FBCF Vs LBCF 2/4/2024 Glaucoma Surgeries - EliasT 20

21. Management of tenon capsule Is main source of fibroblast in area of conj. flap Controversy regarding removal of all or a portion But better to leave if anti fibrosis used 2/4/2024 Glaucoma Surgeries - EliasT 21

22. Antemetabolites used for reduction of fibrosis Placed under scleral flap and conj pockets 2/4/2024 Glaucoma Surgeries - EliasT 22

23. Complications of anti-metabolites Thin avascular cystic bleb Hypotony Endothelial damage and ciliary body destruction Infections: blebitis , Endophthalmitis Scleritis, scleromalacia and necrosis ?? Mention or discuss complications specific to specific antimetabolites 2/4/2024 Glaucoma Surgeries - EliasT 23

24. Scleral flap First cauterize adjacent to corneo limbal junction Partial thickness 3-4mm scleral incision(1/2-2/3 depth) Lamellar flap at limbus is dissected forward, 1mm cornea Can have d/t shapes Square, traingular , semicircular, or trapezoid shape 2/4/2024 Glaucoma Surgeries - EliasT 24

25. Paracentesis Should precede sclerostomy Done with tapered pointed knife or 75 blade Use of VED Avoiding intraoperative hypotony → decrease suprachoroidal effusion- no shallow AC Minimize intraoperative bleeding Temporary solution for postoperative flat anterior chambers Draw back Higher early postoperative IOP Iris prolapse during surgery 2/4/2024 Glaucoma Surgeries - EliasT 25

26. keratectomy Removing a block of peripheral cornea(0.75–1mm) Means of fistulizing Commonly created with the use of a punch PI: To reduce the risk of iris occluding the sclerostomy Complication: amputation of ciliary processes or disruption of zonular fibers 2/4/2024 Glaucoma Surgeries - EliasT 26

27. Closing sclera and conjunctiva Flap closure Fixed, interrupted sutures Adjustable sutures Releasable sutures Closure of conjunctiva: Test the scleral flap integrity before closing the conjunctiva. Many techniques have been developed for conjunctival closure Limbus based flap Fornix based 2/4/2024 Glaucoma Surgeries - EliasT 27

28. Post op care Follow up closely-50% surgery +50% post op care Topical corticosteroids Topical antibiotics Cycloplegic agents- prevent AC shallowing Oral or IV steroid for uveitic glaucoma IOP monitoring Ocular Exam 2/4/2024 Glaucoma Surgeries - EliasT 28

29. Bleb configuration MaBAGS 2/4/2024 Glaucoma Surgeries - EliasT 29

30. 2/4/2024 Glaucoma Surgeries - EliasT 30 MBGS

31. Cont.… Indiana Bleb Appearance Grading Scale IBAGS 2/4/2024 Glaucoma Surgeries - EliasT 31

32. 2/4/2024 Glaucoma Surgeries - EliasT 32

33. Complication 2/4/2024 Glaucoma Surgeries - EliasT 33

34. …cont. 2/4/2024 Glaucoma Surgeries - EliasT 34

35. Hypotony Ocular hypotony is an uncom­mon but potentially vision-threatening event Either an IOP that is 3 standard deviations below normal (<6.5 mm Hg) An IOP low enough to cause visual impairment Manifests in the form of hypotony maculopathy, corneal edema, astigmatism, choroidal effusion Possible causes Conjunctival defect (Bleb leak) Overfit ration Cyclodialysis cleft Ciliochoroidal detachment Inflammation Can be with shallow/flat AC or deep AC . 2/4/2024 Glaucoma Surgeries - EliasT 35

36. Hypotony … 2/4/2024 Glaucoma Surgeries - EliasT 36

37. Pressure patch 2/4/2024 Glaucoma Surgeries - EliasT 37

38. … 2/4/2024 Glaucoma Surgeries - EliasT 38

39. … 2/4/2024 Glaucoma Surgeries - EliasT 39

40. Elevated IOP with shallow AC 2/4/2024 Glaucoma Surgeries - EliasT 40

41. Elevated IOP with deep AC Inadequate filtration Localized: Tenon cyst (encapsulated cyst) Diffuse: Flap resistance (fail bleb) 2/4/2024 Glaucoma Surgeries - EliasT 41

42. Wipe-out or snuff syndrome Severe visual loss after surgery, with no obvious cause Common in Advanced glaucoma (Advanced visual field defects affecting the central field ) Older patients with high preoperative IOP Postoperative complications Mechanism Damage to ON due to anesthesia IOP spikes Decreased blood flow to ON Post op. hypotony 2/4/2024 Glaucoma Surgeries - EliasT 42

43. Bleb related complications Bleb leak Encapsulated bleb Bleb related infection (BRI) - Blebitis and Endophthalmitis Stage of BRI 2/4/2024 Glaucoma Surgeries - EliasT 43

44. Trab failure Risk factors Chronic ocular surface inflammation Previous conj. surgery Aphakia Neovascularization, epithelial down growth West Africa descent, young & male pts Conjunctival scarring Signs of Trab failure Reduced bleb height Increased bleb-wall thickness Vascularization of bleb Loss of conjunctival microcysts Increased IOP 2/4/2024 Glaucoma Surgeries - EliasT 44

45. Management of trab failure 2/4/2024 Glaucoma Surgeries - EliasT 45

46. Ex-Press™ mini-shunt Valveless titanium MRI-compatible stent Inserted under a scleral flap during a modified trabeculectomy Hypotony and hyphaema is lower than with standard trabeculectomy IOP control is equivalent 2/4/2024 Glaucoma Surgeries - EliasT 46

47. Plate-Based Tube Shunt Surgery Designed to shunt aqueous from the anterior chamber to a subconjunctival space Can be divided into valved and nonvalved types Valved devices- Flow restrictor Ahmed valve, krupin Nonvalved devices - No flow restrictor Molteno and Baerveldt 2/4/2024 Glaucoma Surgeries - EliasT 47

48. …cont. 2/4/2024 Glaucoma Surgeries - EliasT 48

49. Indications Failed trabeculectomy with antifibrotics Active Uveitis Secondary glaucoma: neovascular, aniridia Severe conjunctival scarring precluding accurate dissection. Aphakia Contact lens use ???? 2/4/2024 Glaucoma Surgeries - EliasT 49

50. Surgical Technique Exposure Conjunctival Incision Placement of plate Tube placement and management Closure 2/4/2024 Glaucoma Surgeries - EliasT 50

51. Postoperative management Require fewer interventions in the postoperative period compared with trabeculectomy In nonvalved devices in which the tube has been occluded, early IOP spikes are best managed medically Releasing the occluding suture after capsule formed in nonvalved devices. Topical corticosteroids, antibiotics, and cycloplegics 2/4/2024 Glaucoma Surgeries - EliasT 51

52. POP…. 2/4/2024 Glaucoma Surgeries - EliasT 52

53. Angle Surgery Goniotomy and Trabeculotomy Congenital glaucoma is common indication Preoperative evaluation EUA IOP Cornea diameter OD evaluation Pachymetry Any secondary cause 2/4/2024 Glaucoma Surgeries - EliasT 53

54. Goniotomy An incision is made across the TM under direct gonioscopy visualization using a goniotomy knife Allow direct conduit between AC and Schlemm's canal The precise mechanism by which pressure reduction occurs remains obscure 2/4/2024 Glaucoma Surgeries - EliasT 54

55. Indication Primary congenital/infantile open angle glaucoma Other primary glaucoma's (generally poor success) Axenfeld -Rieger syndrome Lowe syndrome Neurofibromatosis Sturge-Weber syndrome Selected secondary glaucoma's Maternal rubella syndrome Open angle glaucoma soon after congenital cataract surgery Uveitic glaucoma (especially with juvenile rheumatoid arthritis) Prophylaxis against acquired glaucoma in aniridia* Early onset juvenile open angle glaucoma 2/4/2024 Glaucoma Surgeries - EliasT 55

56. Complications GA related in infant and neonate Hemorrhage – incision into anterior CB and sclera Cataract – lens injury Infection Epithelial ingrowth Failure – incision anterior to schwalbe line 2/4/2024 Glaucoma Surgeries - EliasT 56

57. Trabeculotomy Cannulating Schlemm's canal from an external approach and then tearing through the TM into the AC Creates a direct communication b/n AC & SC 2/4/2024 Glaucoma Surgeries - EliasT 57

58. Indications Same as for goniotomy, (but preferred in the presence of corneal opacification.) Performed by some surgeons after two goniotomies have failed May be combined with trabeculectomy 2/4/2024 Glaucoma Surgeries - EliasT 58

59. Complications Hyphema Infection Lens damage Iridodialysis Iris prolapse Uveitis Descemet's membrane may be stripped during trabeculotomy 2/4/2024 Glaucoma Surgeries - EliasT 59

60. Non-penetrating surgery Enhance natural aqueous outflow channels by reducing outflow resistance AC is not entered and the internal TM is preserved Two lamellar scleral flaps are fashioned Deep flap excised leaving behind thin membrane contain trabeculum/Descemet membrane Aqueous diffuses from AC to subconjunctival space Reducing the incidence of postoperative over filtration with hypotony and its potential sequelae 2/4/2024 Glaucoma Surgeries - EliasT 60

61. Cont.… Advantages: Avoid some of the complications of traditional glaucoma surgery Can be considered earlier in the disease process Disadvantages: Technically challenging Lower IOP reduction Conjunctival scarring 2/4/2024 Glaucoma Surgeries - EliasT 61

62. Deep Sclerectomy Partial thickness scleral flap Second deep partial thickness scleral flap is fashioned and excised Superficial scleral flap is loosely approximated Conjunctival incision is closed 2/4/2024 Glaucoma Surgeries - EliasT 62

63. Non-penetrating surgery Viscocanalostomy Deep sclerectomy plus viscoelastic substance injection into limited section of Schlemm's canal Canaloplasty Flexible illuminated catheter is utilized to inject viscoelastic into the full 360° of the canal and to pass a suture through it. The suture is then tied, leaving the canal stretched. 2/4/2024 Glaucoma Surgeries - EliasT 63

64. Minimally Invasive Glaucoma Surgery(MIGS) IOP-lowering surgery with Minimally traumatic Via an ab- interno conjunctiva-preserving approach High safety profile Rapid recovery Frequently combined with cataract extraction Provides more modest IOP lowering than trabeculectomy 2/4/2024 Glaucoma Surgeries - EliasT 64

65. Cont.…. MIGS procedures fall into 3 general categories: Stents to Schlemm canal TM disruption Stents to the suprachoroidal space 2/4/2024 Glaucoma Surgeries - EliasT 65

66. Cont.…. Surgery that avoids the formation of a bleb by manipulating the canal of Schlemm by Excision of TM ( Trabectome ®, Kahook Dual Blade®) Bypassing the TM ( iStent inject® or Hydrus®) Dilation of SC (ab- interno canaloplasty with iTrack ®). Implants that result in drainage under Tenon capsule and conjunctiva , (Xen®, Innfocus Microshunt ®) . Mitomycin C is usually injected, ↓bleb fibrosis. Bleb needling is often required postoperatively 2/4/2024 Glaucoma Surgeries - EliasT 66

67. Cont.… 2/4/2024 Glaucoma Surgeries - EliasT 67

68. Indications Mild to moderate glaucoma where The rate of visual field loss is slow The target pressure goal is modest (aiming for 15–17 mmHg). In selected cases combined with phacoemulsification and IOL implantation To reduce the need for topical medication 2/4/2024 Glaucoma Surgeries - EliasT 68

69. Cont.…. 2/4/2024 Glaucoma Surgeries - EliasT 69

70. Complications Implant malposition Hemorrhage Infection Late corneal decompensation Complications that follow trabeculectomy may occur Late failure of MIGS increases the risk of bleb fibrosis Trabeculectomy be subsequently required to control the IOP 2/4/2024 Glaucoma Surgeries - EliasT 70

71. Combined Cataract & Filtering Surgery There are three basic surgical approaches Cataract extraction alone, which may need to be followed by a trabeculectomy later Glaucoma filtering surgery alone, followed by cataract removal later (two-stage Approach) Combined cataract and glaucoma surgery Indications Cataract requiring extraction in a glaucoma pt who has advanced cupping & VF loss Cataract requiring extraction in glaucoma pt with poor compliance Cataract requiring extraction in glaucoma pt requiring multiple medications to control lOP 2/4/2024 Glaucoma Surgeries - EliasT 71

72. Disadvantages of combined surgery versus cataract surgery alone Longer operating room time for procedure More complex postoperative care Slower visual recovery Possibly less IOP control versus trabeculectomy alone Possibly more astigmatism or myopic shift Long-term bleb problems 2/4/2024 Glaucoma Surgeries - EliasT 72

73. References American Academy of Ophthalmologists (2020-2021), Glaucoma. BCSC. J.J. Kanski. Clinical Ophthalmology, A systematic Approach, 9th ed. Shields Text book of Glaucoma 5 th and 6 th edition. AAO website https://www.slideshare.net/namratagupta96780/trabeculectomy-trabeculotomy-goniotomy-and-their-complications 2/4/2024 Glaucoma Surgeries - EliasT 73

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