Pearls from the EGS Guidelines
Publishing date: June 2020
Pearls Manager: Andrew Tatham
Risk factors for conjunctival scarring include young age, African ancestry, inflammatory eye disease, long-term multiple topical medical therapy, recent intraocular surgery, previous conjunctival incisional surgery (including previous filtering surgery), and neovascular glaucoma. Anti-metabolites such as 5-fluorouracil (5-FU) and mitomycin-C (MMC) are frequently used to reduce the risk of postoperative conjunctival scarring. Research suggests that a large surface area of cytotoxic treatment, together with a large scleral flap and accurately sutured fornix-based conjunctival flap, leads to more diffuse posteriorly extended non-cystic blebs, giving a considerable reduction in bleb-related complications. Anti-metabolites should not enter the eye. 5-FU has a pH of 9.0 and one drop (0.05ml) of MMC is enough to cause irreversible corneal endothelial damage.
EGS Guidelines, 4th edition, Page 173.
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2. Melo AB, Spaeth GL. A new, safer method of applying antimetabolites during glaucoma filtering surgery. Ophthalmic Surg Lasers Imaging 2010;41(3):383-5.