Abstract
Purpose: :
To determine the effects of bevacizumab and mitomycin C (MMC), alone and combined, on scaring processes after glaucoma filtration surgery in rabbits.
Methods: :
This is a randomized, prospective, masked-observer study. Thirty New Zealand white rabbits underwent to modified glaucoma filtration surgery (GFS) and were allocated into three groups: Group A bevacizumab (25mg/ml-0.05ml) subconjunctival injection adjacent to the bleb area; Group B MMC (0.2mg/ml) application during trabeculectomy and bevacizumab subconjunctival injection and Group C MMC application alone.The rabbits were killed 30 days after the surgery. Scarring process was addressed by tissue section using Masson and Picrosirius stains on bleb area.The Vascular Endothelial Growth Factor (VEGF) expression on the samples was addressed by immunohistochemical analyses and classified according to the percentage of positive staining and intensity.
Results: :
Group A had the highest level of fibrosis comparing with group B and C (P<0.01). There was no difference between group B and C but the last one showed less fibrosis without reaching statistical significance (P>0.05) (Kruskal Wallis ANOVA).There was less VEGF expression on Group A showed in the number of cells stained and intensity of staining, comparing to groups B and C (P<0.0001). There was no difference between group B and C regarding VEGF expression (Kruskal Wallis ANOVA).
Conclusions: :
The results showed that bevacizumab alone was not as good as associated with MMC or even MMC alone regarding scaring process modulation. There was a higher inhibition of VEGF expression by bevacizumab when it was used alone, but such anti VEGF action wasn’t evident when combined with MMC. The interaction between those drugs, when used simultaneously, could lead to a possible reduction on bevacizumab effect.
Keywords: wound healing • immunohistochemistry • vascular endothelial growth factor