The histopathological effects of reabsorbable polyethylene glycol hydrogel (Coseal) on epidural fibrosis in an experimental postlaminectomy model in rats

Background/aim: To investigate the histopathological effects of reabsorbable polyethylene glycol hydrogel (RPGH, Coseal) on epidural fibrosis (EF) following laminectomy in rats. Materials and methods: A total of 24 rats were equally divided into three groups. In the first group, no treatment was applied after laminectomy (control group, Group 1). In the second group, hemostasis was achieved after laminectomy, and 2 mm absorbable gelatin sponge soaked in saline was placed over the epidural space and the wound was closed (Group 2). In the third group, hemostasis was achieved following laminectomy, and 0.5 mL RPGH (Coseal, Group 3) was squeezed over the dura mater, and the wound was closed. A histopathological examination was undertaken to evaluate arachnoidal invasion and EF. Results: The results of EF in the Group 2 and Group 3 were significantly lower compared to the Group 1 (p = 0.023 and p = 0.002, respectively). No statistically significant difference was found between the Group 2 and Group 3 in terms of EF (p = 0.957). There was also no statistically significant difference between the mean arachnoidal invasion of the three groups (p > 0.171). However, the rate of arachnoidal invasion was the lowest in the Group 3. Conclusion: Intraoperative Coseal, a polyethylene glycol polymer, tends to reduce the risk of epidural fibrosis, although this is not statistically significant.