Studies of long-term changes of tear film and ocular surface epithelium aider trabeculectomy

Objective To investigate the long-term changes of tear film and ocular surface epithelium after trabeculectomy and the influential factors, especially the effects of mitomycin-C(MMC)and bleb shape on ocular surface of glaucoma patients.Methods One hundred and three patients (139 eyes)underwent trabeculectomy more than 6 months ago were included.Routine ocular examinations and ocular surface examinations,including Schirraer I test (S 1 t),break-up time (BUT),fluorescein staining,rose bengal staining,and eonjunctival impression cytology (CIC), were conducted.The precidence of thin-wall bleb in different MMC groups was analyzed.The effects of intraoperative use of MMC and postoperative bleb shape on the tear film and ocular surface epithelium of the patients were analyzed.Results Compared with normal controls,the BUT value was significantly lowerened,ocular surface vital staining was increased,with marked conjunetival epithelial squamous metaplasia of CIC in glaucoma patients.The preeidenee of thin-wall bleb was significantly higher in high-concentration MMC group than low-concentration MMC group and blank control group.The goblet cell density(GCD)of conjunctival epithelium was significantly related to the intranperative use of MMC and postoperative bleb shape.Conclusions Dry eye conditions existed in the glaucoma patients long after trabeculectomy.Intraoperative use of high-eoneentration-MMC may increase the precidenee of thin-wall bleb after trabeculectomy.Decrease of conjunctival GCD in the long term after the operation was related to use of MMC and the elevated conjunctival bleb. Key words: Glaucoma; Trabeculectomy; Mitomycin; Goblet cell