Inadvertent Filtering Bleb

Inadvertent filtering bleb seen in a patient undergone cataract extraction surgery more than 10 years ago.
  • Wound leak under sealed overlying conjunctiva.
  • May occur, particularly following cataract surgery using limbal or scleral incision techniques complicated with wound dehiscence.

Clinical Features

  • Symptoms:
    • May be asymptomatic
    • Tearing due to wound leaking
    • Decreased vision
  • Signs:
    • Subconjunctival microcysts or bleb
    • Wound gape
    • Seidel test (+)
    • Hypotony
    • Corneal folds
    • Shallow anterior chamber
  • May be complicated by hyphema, endophthalmitis, choroidal effusion, choroidal folds or papilledema.


  • No treatment necessary if asymptomatic and no further risks or complications observed.
  • Surgical repair by wound resuturing or bleb excision may be considered in cases with:
    • Large, cystic thin-walled bleb
    • Persistent hypotony
    • Poor tissue apposition
    • Iris prolapse
    • Astigmatism