Bladder and Sphincter Control after Spinal Cord Injury

脊髓损伤后的膀胱和括约肌控制

• 批准号: 6895115
• 负责人: Changfeng Tai
• 金额: $ 23.65万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6895115
• 关键词: afferent nerve; cats; electrodes; electrophysiology; electrostimulus; muscle contraction; nervous system regeneration; neural conduction; neuroregulation; spinal cord injury; spinal reflex; urinary bladder sphincter disorder; urination

DESCRIPTION (provided by applicant): Normal functions of the lower urinary tract are storage and timely elimination of urine voiding. These functions are abnormal after spinal cord injury (SCI). Detrusor and urethral sphincter contract simultaneously during voiding (detrusor sphincter dyssynergia, DSD) and the detrusor also contracts frequently during storage (detrusor hyperreflexia, DH). DSD prevents complete elimination of urine, generates high bladder pressure and requires daily urethral catheterization. High bladder pressure causes vesicoureteral reflux and renal failure in the long-term. Residual urine in the bladder and urethral catheterization, cause cystitis and infection. In addition, DH causes a low bladder storage capacity and transient high intravesical pressures resulting in incontinence, risk for kidney damage and bladder hypertrophy. The problems of the lower urinary tract result in large medical cost and tremendous social and psychological impacts on the patients and their families. The goal of this project is to find new methods to treat both DSD and DH. Although electrical stimulation of sacral anterior roots has been successful to restore bladder control after SCI, it requires transection of sacral posterior roots (dorsal rhizotomy) to prevent DSD and DH. Dorsal rhizotomy is destructive and irreversible, and results in the loss of reflex sexual function and reflex defecation. Our new approach will utilize the remaining and newly emerged spinal reflexes after SCI to restore the lost functions, rather than further damaging the neural pathways by dorsal rhizotomy. During urine storage, we will electrically stimulate pudendal nerve afferent pathways to abolish the hyperreflexic bladder contractions and treat DH. When voiding is attempted, we will suppress pudendal nerve conduction with axonal blocking stimulation to relax the external urethral sphincter and thereby treat DSD. With this approach, a large bladder capacity and low pressure voiding with a minimal residual volume of urine will be expected. Our approach preserves the spinal reflex functions for bowel and sexual organ, and more importantly provides SCI patients the opportunity to benefit from advances in neural regeneration and repair techniques in the future.

描述（由申请人提供）：下尿路的正常功能是储存和及时排除尿液。这些功能在脊髓损伤（SCI）后异常。 逼尿肌和尿道括约肌在排尿期间同时收缩（逼尿肌括约肌协同失调，DSD），并且逼尿肌在储存期间也频繁收缩（逼尿肌反射亢进，DH）。DSD阻止尿液完全排出，产生高膀胱压，需要每天导尿。 高膀胱压力会导致膀胱输尿管反流和长期肾功能衰竭。 膀胱内残留尿及导尿，引起膀胱炎和感染。 此外，DH导致膀胱储存能力低和短暂的高膀胱内压，导致尿失禁、肾损伤和膀胱肥大的风险。 下尿路疾病给患者及其家庭带来了巨大的医疗费用和社会心理影响。 本项目的目标是寻找治疗DSD和DH的新方法。 虽然电刺激骶前根已成功恢复SCI后的膀胱控制，但需要切断骶后根（背根切断术）以防止DSD和DH。 背根切断术是破坏性的和不可逆的，并导致反射性性功能和反射性排便的丧失。 我们的新方法将利用脊髓损伤后残留的和新出现的脊髓反射来恢复失去的功能，而不是通过背根切断术进一步破坏神经通路。 在储尿过程中，我们将电刺激阴部神经传入通路，以消除反射亢进的膀胱收缩和治疗DH。 当试图排尿时，我们将通过轴突阻断刺激来抑制阴部神经传导，以放松尿道外括约肌，从而治疗DSD。 采用这种方法，预计膀胱容量大，排尿压力低，残余尿量最少。 我们的方法保留了肠和性器官的脊髓反射功能，更重要的是为SCI患者提供了从未来神经再生和修复技术进步中受益的机会。