Thin-walled Cystic Bleb

Thin-walled cystic filtering bleb.
  • More frequently developed following full-thickness filtration surgery or an antiproliferative-enhanced trabeculectomy.
  • Complications commonly associated with full thickness filtration procedures are formation of an exuberant bleb due to a lack of aqueous flow resistance, over-filtration with resultant early hypotony, shallow anterior chamber, cataract, corneal decompensation and choroidal detachment.
  • Complications associated with antiproliferative application include corneoscleral, ciliary body and vitreoretinal toxicity, conjunctival wound leak, bleb rupture, and progression of cataract.
  • Vision loss due to hypotony or hypotonic maculopathy, although rare, is more likely associated with the use of mitomycin-C.


  • Thorough evaluation of the bleb post-operatively to assess potential filter failure, conjunctival leak, infection and other complications.
  • Large soft contact lenses (18 - 22 mm) have been reported to be helpful in the management of leaking blebs.
  • Rigid glaucoma shell is also useful in managing friable conjunctival tissues with multiple holes.
  • Excision of the conjunctival tissue or subconjunctival fibrosis, cryotherapy, argon laser, or revision surgery may be needed to improve the filtration bleb.