Spinal Cord Injuries
Conditions
Keywords
Epidural Stimulation, Bladder dysfunction, Spinal cord injury
Brief summary
The investigators propose to determine the electrode configurations that promote functional gains in the storage and voiding phases of lower urinary tract function as a result of activation of spinal circuits with spinal cord epidural stimulation in humans with spinal cord injury. The innovative approach and novel application of the Medtronic Specify 5-6-5 (16-electrode array) epidural device will allow the investigators to determine, with this early feasibility study, specific parameters of spinal cord epidural stimulation and approaches for bladder training needed for lower urinary tract function which will lay the groundwork for expedient translation of this promising technology to larger numbers of individuals with spinal cord injury who currently have limited treatment options. The current proposed study will increase the understanding of human lumbosacral spinal networks and guide the use of innovative therapeutic strategies that would be immediately available to not only improve the motor output during standing and walking but also ameliorate bladder dysfunction and thus improve quality of life in individuals after spinal cord injury.
Detailed description
Deficits in urologic function after spinal cord injury impact quality of life and consistently ranks as a top priority issue in the spinal cord injury population. Bladder dysfunction may manifest as detrusor hyperreflexia (bladder contractions at low volumes, causing incontinence and smooth muscle hypertrophy), detrusor-sphincter dyssynergia (uncoordinated bladder and external urethral sphincter contractions, causing inefficient emptying and smooth muscle hypertrophy), decreased compliance (unable to store urine under appropriately low pressures) and loss of continence, requiring lifelong management, maintenance, and health care visits. Current therapeutic approaches aim to manage both the storage and voiding phases of bladder function and include intermittent catheterization, pharmacologic and surgical interventions. While most of these strategies are necessary for urological maintenance post-injury they oftentimes are associated with side effects and therefore remain inadequate. Therapies addressing recovery of function are still needed. The use of spinal cord epidural stimulation is a promising alternative approach to addressing the primary phases of bladder dysfunction. Additionally, the effects of spinal cord epidural stimulation on bladder alone is not known as its use has been directed towards the locomotor system. Thus, the overall objective of this study is to perform functional mapping in order to identify the spinal cord epidural stimulation configurations (anode/cathode selection, amplitude, frequency and pulse width) at the lumbosacral level that can promote neural control of bladder storage (capacity) and bladder emptying (voiding efficiency) after spinal cord injury.
Interventions
DEVICEEpidural Stimulation
Spinal cord epidural stimulation will be administered through a multi-electrode array implanted in the epidural space over the dorsum of the spinal cord. An implanted package containing stimulating circuits, rechargeable battery, and wireless communication activates the electrodes (16 platinum electrodes arranged in three columns of \[5-6-5\]). The pattern of electrically active electrodes, as well as electrode voltage, stimulating frequency, and stimulating pulse width will be varied to facilitate effects toward bladder function.
Sponsors
National Institute of Neurological Disorders and Stroke (NINDS)
National Institutes of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
University of Louisville
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* stable medical condition without cardiopulmonary disease or dysautonomia that would contraindicate bladder training; * clear indications that the period of spinal shock is concluded determined by presence of muscle tone, deep tendon reflexes or muscle spasms and discharged from standard inpatient rehabilitation; * non-progressive supra-sacral SCI (i.e., upper motor neuron re bladder circuitry); * AIS classification A or B; * at least 2 years post spinal cord injury.
Exclusion criteria
* Painful musculoskeletal dysfunction, unhealed fracture, contracture, pressure sore or urinary tract infection that might interfere with mapping/training; * Clinically significant depression or ongoing drug abuse; * Pregnant at the time of enrollment or planning to become pregnant during the time course of the study * Bladder Botox injections within the past year; * Continent diversion procedures with or without bladder augmentation.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in bladder volume during filling cystometry at low filling pressures | 2 years | The quantitative metric will be the percent changes in either residual volume (measured in ml) alone if no leak occurred or leak volume divided by leak plus residual volumes if a void occurred upon reaching capacity. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in Sexual Function | 2 years | International SCI Data Set Questionnaire for Sexual Function |
| Changes in Bowel Function | 2 years | International SCI Data Set Questionnaire for Bowel Function |
| Changes in Systolic Blood Pressure | 2 years | Percent change without versus with epidural stimulation |
Other
| Measure | Time frame | Description |
|---|---|---|
| Changes in Renal Bladder Ultrasound | 2 years | Measurements include kidney dimensions, parenchymal thickness, renal and aortic velocities, bladder size and thickness. |
Countries
United States
Outcome results
None listed