Performing Trabeculectomy is one thing...managing a failed bleb is all together another ball game. Describes the various precautions to be taken in preventing bleb failure and how to revive a failing bleb

1. Dr Indeevar V Mishra
Glaucoma Department
M.M.Joshi Eye Institute
Hubli.

3. 1. RECOGNISE FAILURE.

4.  Indiana Bleb Appearance Grading Scale-IBAGS,
 Moorfields Bleb Grading System-MBGS,
 CASIA Bleb Assessment Software version 4.0L
(Tomey).
 Aqueous humour cytokine levels [xMAP (Luminex)
multiplex bead-based immunoassay.]

6. 6
Favorable bleb
 Microcysts
 Paucity of vessels
 Diffuse drainage
 Moderate Elevation

7.  Preceded by a gradual increase in IOP
 Change in the bleb's appearance
 Less diffuse
 Avascular (large vessels but
intervening avascular spaces)
 Opalescent
 Flat / very elevated, smooth-domed
 Surrounding fibrotic vascular ring
 Loss of microcysts (fluorescein)
 Pressure does not decrease after massaging.

8.  Young age
 Males
 Black race
 Congenital and juvenile
glaucoma
 Subconjunctival hemorrhage
 Excessive inflammation
 Long-term topical glaucoma
therapy
 Traumatic glaucoma
 NVG
 Reaction to sutures

11. 2. IDENTIFY THE CAUSE

12. Bleb
Failure
Pathological
agents
Physical
agents

14.  Clotting, platelet aggregation, and changes in the diameter
and permeability of the conjunctival and episcleral vessels
 Chemotaxins released recruit polymorphonuclear
neutrophils and macrophages
 Fibroblasts are stimulated by the secretion of the different
growth factors
 The above factors are reduced by minimizing trauma using a small
(2- to 3-mm) perilimbal conjunctival incision, careful sub-
Tenon's dissection with a blunt instrument and careful
cauterization.
14
Inflammatory Phase

15. 15
 Angiogenesis, fibroplasia, granulation tissue formation, and
contraction.
 Fibroblasts start to deposit type 3 collagen on the third
day, a process that peaks by 1 to 3 weeks.
 It can be blunted by the intraoperative use of
mitomycin C (MMC) or 5-fluorouracil (5-FU).

16.  CAT 152 – TGF ß2 #
 VEGF#
 Placental growth factor #
 Rho kinases (ROCK 1 and 2)

17. 17
 The maturation phase is characterized by a more balanced
production and degradation of the extracellular matrix, with
increasing tensile tissue strength.
 Collagen production is switched to the stronger type I
collagen at 4 – 6 weeks.
 This has to tackled by Bleb Needling or Revision.

18. Bleb Needling

19. Reduced egress of
aqueous
Blockade at
internal ostium
Blood
Vitreous
Blockade at the
external ostium
Scleral Flap
Fibrin
Iris
Sub conjunctival
space

20.  Intracameral tissue plasminogen activator
(blocked internal ostium; blood or fibrin clot )
 6 to 12.5 µg
 Frozen (TPA) - 25 g/ 0.1ml is diluted with 0.9 % NaCl
 Low-energy argon laser therapy / Nd:YAG laser
disruption (retract the tissue)
 Iris
 Vitreous
 Internal bleb revision

21.  Most Common cause of early failure
 Tight or Excessive sutures
 Role of Bleb Massage, Laser Suturolysis , Releasable
Sutures & Adjustable Sutures

23. 3.RESTORE BLEB FUNCTION.

25.  Failures – part of the game !
 Glaucoma is essentially a surgical disease, so train
yourself to handle it.
 Take guidance and help from the experts and perform a
Meticulous Surgery.
 Always have a plan B - Use of Drainage Devices or
referral of the case to your senior in time.…