Objective: To investigate the therapeutic effect of the chitosan/polyethylene glycols-succinate/ mitomycin C (CH/PEG-SA/MMC) film on epidural scarring tissues.
Methods: According to a specific proportion of respective materials, the film of CH/PEG-SA/MMC was developed under some condition. Thirty SD rats were selected and randomized into 6 groups with 5 rats in each group. A rat model of lumbar laminectomy was used. The amount of 20 mg of the CH film was implanted into the animals in group I, 20 mg of CH/PEG film in group II, 20 mg of CH/PEG-SA film in group III, 0.05 mg/mL of the MMC soaking for 5 minutes in group IV, 20 mg of CH/PEG-SA/MMC film in group V, and nothing was done in group VI. Specimens were harvested 4 weeks after the above procedures and were then subjected to immunohistochemical and histological examinations to compare their therapeutic effects on epidural cicatricial tissues.
Results: All rats were in good conditions after operation, without gait abnormality, restlessness, infection and death. There was no significant difference among the 6 groups in the postoperative Rydell score (P < 0.05). The content of hydroxyproline in groups I, II, III, IV, V and VI was (0.570 8 +/- 0.345 0), (0.728 6 +/- 0.150 6), (0.553 4 +/- 0.122 3), (0.313 3 +/- 0.106 4), (0.261 9 +/- 0.102 1) and (1.020 1 +/- 0.120 6) microg/mg, respectively. There was a significant difference between groups IV, V and groups I, II, III (P < 0.05), and there was significant difference between group VI and the rest 5 groups (P < 0.05). According to the histological observation, group V had less collagenous fiber paralleling the dura mater, with few inflammatory cells infiltration, with few capillary vessels and no reaction of macrophages.
Conclusion: CH/PEG-SA/MMC films can effectively reduce the amount of Hyp in epidural scarring tissues after lumbar laminectomy and therefore is a good treating method in preventing scarring tissue adhesion.