title: Influence and mechanism of He-Ne laser on scar formation of filtration canal after trabeculectomy in rabbit.
abstract: OBJECTIVE
  To investigate the influence of He-Ne laser on connective tissue growth factor (CTGF) expression and collagen formation of fibroblast in filtration site after trabeculectomy in rabbit, and to discuss the mechanism for preventing scar formation with He-Ne laser in vivo.
  
  
  METHODS
  The upper nasal limbus area next to the upper rectus muscle in right eyes received 10 minutes He-Ne laser irradiation (200mW/cm(2)) every day for three days, the left eyes served as control. Twenty-four hours after the last irradiation, both eyes of the rabbits were took trabeculectomy surgery. The expressions of CTGF in the filtration area were tested on the 7(th), 14(th) and 28(th) day after surgery and collagen density was tested on the 14(th) and 28(th) day after surgery. Each of the time point had 7 rabbits.
  
  
  RESULTS
  The expression of CTGF was lower than that of the control group's on the 7(th) and 14(th) day after trabeculectomy surgery (P=0.01, P=0.005). When examined on the 14(th) and 28(th) day, the collagen density of irradiation group were significantly lower than that of the control group's (P=0.013, P=0.01).
  
  
  CONCLUSIONS
  Pretreating the filtration area with 200mW/cm(2) He-Ne laser may be helpful in preventing scar formation after trabeculectomy in rabbit, possibly due to downregulation of the expression of CTGF and collagen synthesis in fibroblasts. He-Ne laser may be developed into a new scar preventing method in filtration surgery.
authors.affiliation: Department of Ophthalmology, the Affialted Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China.
authors.forename: Rui-Lin
authors.initials: RL
authors.lastname: Wang
authors.forename: Gui-Gang
authors.initials: GG
authors.lastname: Li
authors.forename: Zhi-Qi
authors.initials: ZQ
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiang
authors.forename: Hong
authors.initials: H
authors.lastname: Zhang