Topical application of tacrolimus prevents epidural fibrosis in a rat postlaminectomy model: histopathological and ultrastructural analysis.

AIM Postlaminectomy epidural fibrosis is the formation of scar tissue over the dura mater following posterior spinal surgery. This devastating complication is responsible for the substantial amount of failed back syndromes. MATERIAL and METHODS Twenty male Wistar-Albino rats each weighing 350-400 grams were used. Following L3-L5 laminectomy, the rats were randomly divided into 2 groups, with 10 rats in each group. In the control group, only a laminectomy was performed. In the drug group, 5 mg/ml tacrolimus was topically applied with a cotton pad soaked with the drug solution for 5 minutes. The animals were killed on the 30th postoperative day injecting a lethal dose (250 mg/kg) of pentobarbital and the involved dural segments were removed for histopathological and ultrastructural evaluations. RESULTS Epidural scar thickness and the density were significantly lower in the animals treated with tacrolimus than those of the control group. CONCLUSION Promising evidence regarding the anti-scar potential of tacrolimus merits further research to optimize the dosage and the usage of the drug.