脊髓前动脉损伤后脊髓病理演变的实验研究

目的观察脊髓前动脉损伤后脊髓组织形态学演变过程,研究病理机制.方法以家犬为实验模型,损伤脊髓前动脉后进行肉眼、光镜和电镜动态观察,定量测定坏死神经元.结果脊髓前动脉损伤2h运动神经元变性,轴索病变,6h神经元坏死,24h脊髓水肿达到高峰,7d髓内出血最明显.在脊髓前动脉损伤节段,24h 30%～40%的运动神经元坏死,3d达80%,7d以后95%以上.病变均位于脊髓2/3.脊髓前动脉损伤节段变性坏死最严重,相邻节段其次,尾侧脊髓坏死量逐渐减少.结论脊髓前动脉损伤后脊髓缺血性病变是渐进和不可逆的,可引起广泛节段脊髓病变.

The Pathological Study of Spinal Cord Ischemia Caused by Anterior Spinal Artery Injury in Canines

Objective:To observe the histomorphologica l outcome of medullary ischemia caused by anterior spinal cord artery injury,research the pathologic mechanism.Methods:I njured cervical anterior spinal artery.The pathology of spinal cord was observed grossly and under light microscope as well as transmission electron microscope, and determined quantificationally the necrotic motor neurons.Results:Within 2 ho u rs of anterior spinal artery injury,axonal and motor neurons degeneration occurr ed.At 6 hours postischemia motor neurons necrosis were shown.Edema and demyelina tion was observed distinctly in spinal cord at 24 hours,however,motor neurons ne crosis and hematomyelia worsened with time so that by 7 days.The pathological ch anges involved primarily only the ventrocolumna,funiculus anterior and funiculus lateralis of spinal cord.Motor neurons necrosis spreaded into adjacent segments of the cord,and extended more prominently to the caudal side of spinal cord.Con cl usions:After cervical anterior spinal artery injury,the evolution of pathologica l changes was gradual and irreversible.Motor neurons necrosis more significantly extended to adjacent segments and caudal side.