Comparison to the effect of pazopanib and bevacizumab on wound healing with steroid in experimental glaucoma filtration surgery

Glaucoma which usually appears with high intraocular pressure and degeneration of retinal ganglion cells is a progressive optic neuropathy and is the second cause of preventable blindness in the world. Rapid wound healing is the primary cause of the surgical failure in glaucoma surgery. This study was performed for the comparison of the effects of bevacizumab and pazopanib with corticosteroids on wound healing after trabeculectomy. In the study, 35 New Zealand white rabbits were randomly divided into five groups by providing seven rats for each group. Apart from the first group, limbus-based trabeculectomy was performed for the eyes of rabbits. No postoperative treatment was administered for group I. Topically administered saline, prednisolone acetate (%1), bevacizumab 5mg/ml, pazopanib 5mg/ml were applied for groups II, III, IV and V respectively with a daily dose of six hours intervals for 28 days. Anterior segment photographs were taken on the 1st, 3rd, 7th, 14thand the 28th days for evaluating bleb vascularization. Operated eyes of the rabbits were enucleated on the 28th day after the operation and histopathological sections were taken from the bleb sites. Fibroblasts and mononuclear cells were stained with Masson-Trichrome and Hematoxylin-Eosin and evaluated histopathologically. Additionally, PDGF-β, FGF-β and VEGF staining intensity were evaluated immunohistochemically. In terms of bleb vascularity, there was no difference among the treatment groups on the 1st and 3rd days. On the 7th, 14th and the 28th days, bleb vascularity in groups IV and V were lower than those in groups II and III (p<0.05, p<0.05, p<0.05, p<0.05, respectively). In group IV and V statistically no significant difference was observed (p>0.05). The fibroblast numbers were significantly lower in groups IV and V vs the groups II and III (p<0.05, p<0.05, p<0.05, p<0.05, respectively). Similarly, there was no statistically significant difference between groups IV and V (p>0.05). In terms of the number of mononuclear cells, it was observed that the cell count in group I was greater than that of group II (p<0.05). However, no significant between the treatment groups (p>0.05, p>0.05, p>0.05, respectively). Group IV and V had lesser FGF-β and VEGF immunohistochemical staining intensity than those of groups II and III (p<0.05, p<0.05, p<0.05, p<0.05, respectively). There was no significant difference between groups IV and V (p>0.05). PDGF β immunohistochemical staining intensity in group V was lesser than those of groups II, III and IV (p<0.05, p<0.05, p<0.05, respectively). Although the PDGF staining intensity in group IV was lesser vs group II (p<0.05), it was not significant when compared with group III (p>0.05). As a result; it was concluded that bevacizumab and pazopanib might be good alternatives of corticosteroid treatment on delaying wound healing in glaucoma surgery. Keywords: Trabeculectomy, wound healing, corticosteroid, bevacizumab, pazopanib