Research on the relationship of mitomycin-C and filtration bleb complications

Objective To analyze the relationship of mitomycin-C(MMC)and filtration bleb related complications in trabeculectomy.Methods Thirty-one cases(36 eyes)with bleb related complications after applying MMC in trabeculectomy were analyzed.The effect of MMC concentration,applying duration and placement site on the morphology of the bleb,intraocular pressure(IOP),change of vision,and macular edema were considered.Results In 31 cases(36 eyes),bleb leakage was found in 11 eyes,and bleb infection in 1 eye,enormous thin-wall bleb in 7 eyes,simple thin-wall bleb in 7 eyes,low IOP complicated with cystoid macular edema in 10 eyes.The mean time of onset of the bleb complications were 17 24±20 00 months.The mean visual sight decreased more than 2 lines.The bleb complications were significantly related to the placement site of MMC(r=0 578, P =0 008),and positively related to the applying duration(r=0 456, P =0 038),but not related to the MMC concentration(r=-0 3991, P =0 073).The decrease of IOP was negatively related to the MMC concentration(r=-0 540, P =0 005).Conclusions Filtration bleb complications after trabeculectomy were closely related to the applications of MMC.Simultaneous placement of MMC under the conjunctival and scleral flap and longer duration of placement tend to cause the complications.And high concentration of MMC may be more likely to cause low IOP.