硬膜外腔复合液注射对实验动物影响的病理学研究

Pathological effects of epidural injection of compound solution on experimental animals

摘要:

目的：通过对硬膜外腔复合液注射后实验动物硬膜外腔及神经根的病理学观察，了解硬膜外腔复合液注射是否会引起椎管内粘连以及能否产生神经根的炎症反应。方法：健康成年日本大耳白兔24只，单纯随机分成A、B、C、D 4组，每组6只，A组为正常对照组，其余3组为给药组：B组为激素+麻醉剂组、C组为激素+麻醉剂+维生素B组、D组为激素+麻醉剂+维生素B+中药组。采用硬膜外腔注射的方法，将3种不同配方的复合夜分别注射到兔的硬膜外腔。每只动物每周给药1次，共给药4次，分别于停止给药后的第1周、第4周进行取材、固定及制片，然后进行观察。结果：肉眼未见纤维组织增生及瘢痕形成，光镜下HE染色可见有部分标本硬膜外有炎性渗出，可见多数炎性细胞，硬膜外神经根内有炎性渗出。特殊染色未见异常；免疫组化染色，4周时B、C、D 3组硬膜下及硬膜外渗出物中含有Ⅱ型胶原纤维，8周时B、C、D 3组硬脊膜厚薄不一，局部硬膜外可见有少量Ⅱ型胶原纤维增生。电镜观察4周时，B组可见1成纤维细胞，C组可见1个巨噬细胞，D组有髓神经纤维局部髓鞘增厚，神经内膜内可见成纤维细胞和胶原原纤维；8周时，B、C、D 3组主要表现为成纤维细胞增多。结论：每周1次、连续4次的硬膜外腔复合液注射，在4周内即可出现硬脊膜及神经根周围的轻度炎症反应及轻度的Ⅱ型胶原纤维增生，8周内这种变化仍然存在，但脊髓和神经根未发生器质性改变。如果穿刺部位准确，该治疗方法应该是安全可行的。

Abstract:

Objective：To investigate whether epidural injection of compound solution can cause intraspinal adhesion and inflammatory reaction of nerve roots by observing the pathological condition of epidural cavity and nerve root after the injection. Methods：Totally 24 healthy adult white Japanese rabbits were randomly divided into four groups equally（n=6）：control group（group A），steroid + narcotic injection group（group B），steroid + narcotic+ vitamin B injection group（group C），steroid + narcotic+ vitamin B+ traditional Chinese medicine injection group（group D）. In group B，C，D，each rabbit was given epidural injection of compound solution once a week for four weeks. The dura mater，nerve roots，and spinal cord specimens were performed for pathologic detection at the 1st，4th and 8th week respectively after discontinuation. Results：Neither fibroplasia nor cicatrization was observed by visual inspection. The results of HE staining indicated the presence of hemaleucin effusion and phlogistic infiltration in the epidural cavity，thickening of the dura mater and inflammatory exudation around the nerve roots in partial specimens. No abnormality was seen in specific staining. Immunohisto－chemistry showed that type Ⅱ collagen fiber proliferation occurred in the subdural and epidural cavity at the 4th week in group B，C and D and dura maters were slightly thicker in group B，C and D than in group A at the 8th week. Under the electron microscope，desmocyte in group B，macrophage in group C，focal thickening of the myelin sheath and endoneurial collagen fibril in group D were observed at the 4th week. Increasing number of desmocytes in group B，C，D at the 8th week were found. Conclusions：Mild inflam－mation and slight type Ⅱ collagen fibers proliferation can be detected around the spinal cord and nerve roots after epidural injection of compound solution once a week for consecutive four weeks. No organ damage in spinal cord and nerve root can be found if these changes exist within eight weeks. Epidural injection of compound solution is feasible if the puncture is accurate.