Mitomycin C, 5-fluorouracil, and cyclosporin A prevent epidural fibrosis in an experimental laminectomy model

Abstract

This study examined the preventive effects of the local application of mitomycin C (MMC), 5-fluorouracil (5-FU), and cyclosporine A (CsA) in minimizing spinal epidural fibrosis in a rat laminectomy model. Thirty-two 2-year-old male Wistar albino rats, each weighing 400 +/- 50 g, were divided into four equal groups: sham, MMC, 5-FU, and CsA. Each rat underwent laminectomy at the L5-L6 lumbar level. Cotton pads (4 x 4 mm2) soaked with MMC (0.5 mg/ml), 5-FU (5 ml/mg), or CsA (5 mg/ml) were placed on the exposed dura for 5 min. Thirty days after surgery, the rats were killed and the epidural fibrosis, fibroblast density, inflammatory cell density, and arachnoid fibrosis were quantified. The epidural and arachnoid fibroses were reduced significantly in the treatment groups compared to the sham group. Fibroblast cell density and inflammatory cell density were decreased significantly in the MMC and 5-FU groups, but were similar in the sham and CsA groups. The decreased rate of epidural fibrosis was promising. Further studies in humans are needed to determine the short- and long-term complications of the agents used here.

Fig. 1

The arrow indicates increased fibrosis (Grade 3) in the dura in sham, HE ×40

Fig. 2

Grade 0 fibrosis in the dura, the dura is free of scar tissue, it contains blood vessels only, HE ×40

Fig. 3

Grade 1 fibroblast density, note the lower number of fibroblast cells, HE ×200

Fig. 4

Grade 3 fibroblast density, note the increased number of fibroblast cells, HE ×200