Experimental And Clinical Studies On Bladder Function Reconstruction By The Use Of Somatic Reflexes

Neuropathic bladder dysfunction after spinal cord injure (SCI) is popular in paraplegic patients and present a major health problem. Treatment of this disease is complex and a challenge in medical and society. Although attempts at urinary bladder reinnervation have been described since 1907, unfortunately an ideal therapy has not been achieved till today. To restore bladder function after SCI, we has designed a new artificial "tendon-CNS-bladder" reflex arc study for 5 years. That means an artificial modified efferent branch will pass the somatic motor impulses to the bladder and the bladder micturition can be controlled by this reflex arc. In this study, in order to reveal which nerve cell the reflex arc is composed and it's morphological character, as well as to study the urodynamic property by artificial reflex arc and to probe in the mechanism of micturition caused by knee jerk, the animal experiment was established. Then for the requirement of new operation, pertinent clinical anatomy was studied in specimens. Also clinical study was performed in 4 patients treated with the new way so as to judge the value of this new operation, determine it's indications and select suitable method for different Sd patients. The dissertation is divided into three parts: Part I: Experimental Study on bladder function reconstruction with somatic reflexes Objective To reveal which nerve cell the reflex arc is composed and it's morphological character, as well as to study the urodynaniic property by artificial reflex -6- arc, so as to probe in the mechanism of micturition caused by knee jerk and lay foundation for clinical study. Methods 1. Animal model: 5 dogs performed L5-S2 ventral roots crossover anastomosis to design endon-CNS-bladder?reflex arc pathway. 2. A year later, all 5 dogs were underwent electrophysiological study and bladder urine function study. 3. Neural tracing study with horseradish peroxidase (HRP) and the morphology of regeneration axons with computer picture analysis were preceded after physiological study. Results 1. HRP positive cells appeared in L5 ventral horn and like somatic motor nerve cell. There are many axons regenerate through anastomosis areas. 2. When all spinal roots but the artificial reflex arc roots were transected, stimuli to any point of reflex arc results in evoked potential recorded beyond the anastomosis area, bladder detruser EMG and rapidly increase of intravesical pressure. 3. Bladder pressure curve evoked by artificial arc is a double peak curve. The pressure between the second peak and urethral pressure contribute to the functional micturition. Conclusion 1. Animal model for bladder functional reconstruction with artificial reflex arc can be successfully copied by crossover anastomosis of L5-S2 ventral roots and there is no influence to low limbs. 2. The CNS in endon-CNS-bladder?is a group of somatic motor cells located in L5 ventral horn. That means the CNS of bladder can remove from S2 lateral horn to L5 ventral horn by L5-S2 crossover anastomosis of ventral roots. The number of regeneration axons meets the requirement of bladder functional reconstruction. 3.endon-CNS-bladder?reflex arc can translate AP successfully and cause bladder detruser and urethral sphincter contraction to meet functional micturition. 4. The bladder detrusor and urethral sphincter contraction is not in-phase that one of the mechanism of micturition with artificial reflex arc.