Application of biological dural graft made by meninges from porkers

Abstract

Background Presently, over 40 kinds of dural grafts have been successively used in clinic. Among them, lyophilized human dura mater with good histocompatibility and less complications is applied most widely. But there are a few reports on cases of infected spongiform encephalopathy following application of lyodura. More ideal repair materials deserve to be further investigated. Objective To investigate the efficiency and safety of biological dural graft made by meninges from porkers to repair meningeal injury. Design A self-control observation. Setting Wuhan General Hospital of Guangzhou Military Area Command of Chinese PLA. Materials Sixteen New Zealand Rabbits, of either gender, weighing from 2 to 3 kg, of clean grade II, with the age of 0.5–1 year, were involved in this experiment. The involved rabbits were provided by the Animal Experimental Center of the First Military Medical University of Chinese PLA. Biological surgical patch (dural graft) was developed by Guangdong Guanhao Biotechnological Co., Ltd. It was processed by using meninges from porkers by tissue engineering technology. Methods This experiment was carried out in the Experimental Center of the 157 Hospital of Chinese PLA between December 2003 and June 2004. ▪ The experimental rabbits were anesthetized. Dura mater was exposed from two sides of postmedial line of coronal suture. A rectangular dura mater about 8 mm×8 mm in size was cut off. Then a biological surgical patch (dural graft) was sheared into insert with 8 mm diameter and sutured. The left dura mater was untouched and used as control. Scalp was sutured, and postoperative wound healing and recovery were observed. ▪ The anesthetized rabbits were sacrificed at postoperative 3, 14, 30 and 90 days, 4 rabbits once. The whole head was cut off, and its scalp was removed. Afterwards, the head was fixed by formalin. Tissues in operative site were obtained, performed routine paraffin embedding, sliced and conducted HE staining, finally, the sections were observed. White blood cells in venous blood were counted before operation and execution, separately. The obtained data were statistically analyzed. Main outcome measures ▪ Wound healing and recovery following implantation of dural graft. ▪ The amount of white blood cells in venous blood from rabbits at each time point before operation and before execution. ▪ Histological examination results of operative site. Results Sixteen experimental rabbits were involved in the final analysis. ▪ The experimental rabbits of each group had no local infection, effusion and abnormal appearance. They had good wound healing and were normal to access to food. ▪ There were no significant differences in amount of white blood cells in venous blood from experimental rabbits between at each time point after modeling and before operation ( P > 0.05). ▪ Pathological observation of operative site: At postoperative 3 days, local acute inflammation repair reaction appeared; At postoperative 2 weeks, chronic inflammatory reaction appeared, endodermis in artificial dural graft formed, and artificial dural graft and host dura mater healed; In postoperative 1 month, wound began to chronically recover; In postoperative 3 months, host blood capillary began to form in artificial dural graft based on chronic repair. In all the control sides, fibroplasia was found, and a few neutrophils were found at postoperative 2 weeks. Conclusion Biological surgical patch has high stability and good histocompatibility. It can provide dural epithelial epithelium, effectively prevent against the conglutination of scalp tissue and brain tissue, and avoid the leakage of cerebrospinal fluid.