Xianyou Zhen

Publications (2)2.97 Total impact

• Article: Clinical study of reconstructed bladder innervation below the level of spinal cord injury to produce urination by Achilles tendon-to-bladder reflex contractions.

  Haodong Lin, Chunlin Hou, Xianyou Zhen, Zhen Xu
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  ABSTRACT: Neurogenic bladder dysfunction following spinal cord injury (SCI) is a major medical and social problem for which there is no ideal treatment strategy. In the present study, the authors analyze the effectiveness of neurogenic bladder reinnervation in patients with SCIs by using Achilles tendon reflexes below the paraplegic level. Spinal root anastomoses were performed in 12 paraplegic patients with hyperreflexic neurogenic bladder and detrusor external sphincter dyssynergia (DESD) caused by complete suprasacral SCI, in an attempt to reinnervate the bladder. The surgery anastomosed the unilateral proximal end of the S-1 ventral root and the distal end of the S-2 and/or S-3 ventral roots to build the Achilles tendon-to-bladder reflex, while the S-1 dorsal root was kept intact as the trigger for micturition after axonal regeneration. All patients underwent urodynamic evaluation before surgery and at follow-up. The mean follow-up duration was 3 years. Of the 12 patients, 9 (75%) regained satisfactory bladder control within 6 to 12 months after ventral root microanastomosis. In these 9 patients, urodynamic studies revealed a change from detrusor hyperreflexia with DESD and high detrusor pressure to almost normal storage and synergic voiding without DESD. The average bladder capacity increased from 258 +/- 33 ml to 350 +/- 49 ml, residual urine decreased from 214 +/- 36 ml to 45 +/- 11 ml, and urinary infections were not observed. Patients with impaired renal function experienced a full recovery. Three patients failed to show any improvement after the operation. These results suggest the effectiveness of bladder innervation below the level of SCI to produce urination by Achilles tendon-to-bladder reflex contractions, and might therefore provide a new clinical approach to reconstructing spasmodic bladder urination function.
  Journal of Neurosurgery Spine 06/2009; 10(5):452-7. · 1.53 Impact Factor
• Article: Bypassing spinal cord injury: surgical reconstruction of afferent and efferent pathways to the urinary bladder after conus medullaris injury in a rat model.

  Haodong Lin, Chunlin Hou, Xianyou Zhen
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  ABSTRACT: Afferent and efferent nerve function in the atonic bladder caused by conus medullaris injury in a rat model was established by intradural microanastomosis of the left L5 ventral root (VR) to right S2 VR to restore pure motor-to-motor reinnervation coupled with extradural postganglionic spinal nerve transfer of L5 dorsal root (DR) to S2 DR for pure sensory-to-sensory reinnervation. Early function of the reflex arc was evaluated by electrophysiological study, as well as by intravesicular pressure measurement and histological examination. The results demonstrated that single focal stimulation of the left S2 DR elicited evoked potentials at the left vesicular plexus before and after horizontal spinal cord damage between the L6 and S4 level. Bladder contraction was successfully initiated by trains of stimuli targeting the left L5-S2 DR anastomosis. Achievable bladder pressures and amplitude of bladder smooth muscle complex action potentials were unchanged before and after induced paraplegia and comparable to those of the control. Prominent axonal sprouting was seen in the distal part of nerve graft. Both afferent and efferent nerve pathways in the atonic bladder can be reconstructed by suprasacral motor-to-motor and sensory-to-sensory nerve transfer after spinal cord injury in rats. This reconstructive strategy has significant potential in clinical application.
  Journal of Reconstructive Microsurgery 10/2008; 24(8):575-81. · 1.43 Impact Factor