人工膀胱反射弧的远期功能观察

目的 :建立犬人工膀胱反射通路 ,以恢复脊髓损伤后的膀胱功能 ,观察人工反射弧的远期功能状态。方法 :将右L5前根近端与右S2 前根远端在硬膜囊内吻合 ,经轴突再生后 ,建立膝腱—脊髓中枢—膀胱这一新的人工膀胱反射通路 ,通过刺激膝腱激发排尿。结果 :神经根吻合术后 18个月 ,T10 平面截瘫 48h后 ,通过电刺激传入神经 ,经新建的反射弧引出的膀胱收缩平均可达正常的 84% ,敲击膝腱引出的膀胱收缩平均达正常的 6 2 % ;电刺激右L5后根和右股神经 ,均可记录到膀胱逼尿肌肌电图 ,其形态和波幅与对照组相似。结论 :体神经的运动传出支通过轴突再生能够长入自主神经的副交感性纤维 ,并具有良好的传导运动兴奋的功能 ;利用截瘫平面以下健存的体反射 ,通过神经根吻合的方法 ,可建立人工膀胱反射弧 ,实现患者的控制性排尿。

Establishment of Artificial Reflex Arc after Spinal Cord Injuryi:Long Term Observation and Final Function Test

Objective:To establish an artificial reflex arc in canines to reinnervate the neuropathic bladder and restore bladder function after spinal cord injury.To observe the long term result and the final function of the artificial reflex arc.Methods:This is achieved by intradural microanastomosis of the right L 5 ventral root to S 2 ventral root.After axonal regeneration,the pateller ligament spinal cord center bladder reflex pathway was extablished,and voiding was induced by knocking the pateller ligament.Results:After microanastomosis and axonal regeneration for 18 months,48 hours after spinal cord was transected horizontally at the T 10 segment level,bladder contraction was very quickly initiated by trains of stimuli (1000mV,10Hz,2s)of the right L 5 dorsal root and bladder pressure increased rapidly to average 84% of normal compared to controls.Bladder contraction induced by knocking the pateller ligament increased to average 62% of normal compared to controls through the new bladder reflex arc.Stimuli(3 8mA,1 0Hz)of the right L 5 dorsal root and femoral nerve resulted in electromyogram(EMG) recorded from the detrusor of bladder.Conclusion:The somatic motor fibers can regenerate into the parasympathetic endoneurial tubes of autonomic nerve.Using the survived somatic reflex under the horizon of spinal cord injury to reconstruct the bladder autonomic reflex arc by intradural microanastomosis of ventral root is practical in the canine model and may have a potential of clinical application.