AIM: To observe the morphologic changes of of filtration blebs after trichostatin A treatment in an experimental glaucoma filtration surgery(GFS).

METHODS: Subconjunctival injection TSA, mitomycin C(MMC)and PBS during the filtering surgery in rabbits. The morphologic changes of filtration blebs were evaluated by Krofeld score method postoperatively days 3, 7, 14, 21, and 28.

RESULTS: TSA induced filteation bleds were elevated diffusely within 14d and cystic blebs formed 28d, filtration bleb score was significantly higher in TSA group than that in PBS group.

CONCLUSION: TSA can keep the aqueous humor outflow by inhibiting scar formation and prolong the existence of the filtration bleb.