Prevention of epidural fibrosis in rats by local administration of mitomycin c or daunorubicin

AIM: Epineural adhesion after peripheral nerve surgery is common. The purpose of this study was to evaluate the macroscopic and histopathologic effects of topical mitomycin C and daunorubicin on epineural scar formation. MATERIAL and METHODS: In this study, we used 15 rats (30 nerves). Two test groups and one control group were created. Sciatic nerve exposure was created bilaterally in each group (30 nerve examinations in total). In experimental group 1, cotton pads that had absorbed mitomycin C (0.5 mg/ml) were placed onto the nerves for 5 minutes while in experimental group 2, cotton pads that had absorbed daunorubicin (0.2 mg/ml) were placed onto the nerves for 5 minutes and cotton pads that had absorbed saline were applied to the control group. Eight weeks after the first surgery, surgical dissection was performed for the evaluation of neurolysis sites. Epineural adhesions were classified utilizing a numerical grading layout. RESULTS: We did not find any adverse effect with topically applied mitomycin C and daunorubicin. Within the 3 groups, no significant difference was seen in skin and fascia -muscle cavity closure (p>0.05). Macroscopically, mitomycin C and daunorubicin decreased the adhesion of sciatic nerve to adjacent structures. There was intensive epineural scar formation in the control group. Scar tissue thickness and fibroblast/fibrocyte cell number were less in the two test groups compared with the control group (p<0.001). There was no statistical difference between the two test groups. CONCLUSION: Epineural scar formation after peripheral nerve surgery may be reduced by using topical application of mitomycin C and daunorubicin.