摘要
目的:探讨犬马尾神经慢性压迫的病理变化与脊髓诱发电位(CESEP)和MRI之间的关系,为临床诊治该病和判断预后提供实验依据.方法:家犬10只,2只为对照组,8只为实验组,在L5～L6椎板下,潜行置入可控式硅胶水囊,对照组不注水,实验组每周注入0.5ml,在压力为20mmHg(第4周)、60mmHg(第7周)及120mmHg(第9周)和120mmHg持续1周(第10周)后随机抽取2只犬,用诱发电位和MRI检查后处死动物,观察其相应的组织学变化.结果:当压力＜60mmHg,椎管狭窄＜50%时,诱发电位潜伏期延长,波幅下降,但无统计学意义,MRI示硬膜外脂肪存在,马尾神经无压迫,病理学无器质性变化;当压力≥60mmHg,椎管狭窄≥50%时,诱发电位潜伏期延长,波幅下降,有显著性差异.MRI示硬膜外脂肪消失,受压处硬膜囊明显变细,局部马尾信号增高,病理学示神经纤维出现不可逆变化.结论:随着压力和压迫时间的增加,马尾神经的病理变化逐渐加重,诱发电位和MRI均有相应变化,MRI示椎管狭窄≥50%时病理学上神经纤维出现不可逆变化.
Objective:To find out the relationship among the pathologic changes,the spinal evoked potentials and MRI in canine with the chronic compression of cauda equina,and to provide the experimental evidences to the diagnosis,treatment and prognosis of the disease.Method:10 dogs were divided into 2 groups,two in the control group,eight in the experiment group.A controllable silica gel water sac was laid in the epidural space of L5~L6,water was not filled into the sac in the control group,and 0.5ml of water was filled into the sac every week in the experiment group.At the time of the pressure in the sac reaching 20mmHg(4th week),60mmHg(6th week),120mmHg(9th week) and 1 week after the pressure reaching 120mmHg(10th week),2 dogs selected at random in the experiment group were observed with SEP and MRI,then with the histological methods after the dogs were killed.Result:When the pressure was less than 60mmHg and the area of the spinal canal decreased by less than 50%,the latent period of SEP delayed and the amplitude of SEP descended,but there was no significant difference compared with the control group.The epidural fat tissue was still shown in MRI and there was no compressive evidence of cauda equina.No significant histological changes were observed.When the pressure was more than 60mmHg and the area of the spinal canal decreased by more than 50%,the latent period of SEP delayed and the amplitude of SEP descended,and there was significant difference compared with control group.The absence of the epidural fat tissue,narrowing of dural sac and heightened signal of cauda equina were shown in MRI.The significant histological changes could be observed in nervous fiber.Conclusion:With the increasing of the pressure and the time of compression,the pathologic changes get more and more severe along with the corresponding changes of SEP and MRI.The significant histological changes can be observed in nervous fiber with the area of epidural canal decreases more than 50%.
出处
《中国脊柱脊髓杂志》
CAS
CSCD
2005年第5期300-303,i003,共5页
Chinese Journal of Spine and Spinal Cord
基金
国家自然科学基金项目(编号30271310)
关键词
马尾神经
慢性压迫
诱发电位
MRI
组织学
Cauda equina
Chronic compression
Evoked potentials
MRI
Histology
